Oracle 12c新特性--ASMFD（ASM Filter Driver）特性

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发布时间：2019-05-10

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Oracle 12c新特性--ASMFD（ASM Filter Driver）特性

从Oracle 12.1.0.2开始，可以使用asmfd来取代udev规则下的asm磁盘设备绑定，同时他也具有过滤非法IO操作的特性。ASMFD是ASMLIB和UDEV的替代产品，实际上，ASMFD也用到了UDEV。

可以在安装GRID时配置ASMFD，也可以在安装Grid后再进行配置。

检查操作系统版本是否支持ASMFD，可以使用如下代码：

acfsdriverstate -orahome $ORACLE_HOME supported

ASMFD 是 12.1 中就引入的新特性，它可以不用手动配置 ASM 磁盘，更重要的是它可以保护磁盘被其他非 Oracle 操作复写，例如 dd ， echo 等命令。

下面的环境基于RHEL 7.4,测试将UDEV存储转移到AFD磁盘路径。

一、afd配置调整

1、root用户下添加grid环境变量

[root@rac1 ~]# export ORACLE_HOME=/u01/app/12.2.0/grid

[root@rac1 ~]# export ORACLE_BASE=/tmp

2、获取当前asm磁盘组发现路径

[root@rac1 ~]# $ORACLE_HOME/bin/asmcmd dsget

parameter:/dev/asm*

profile:/dev/asm*

3、添加AFD发现路径

[root@rac1 ~]# asmcmd dsset '/dev/asm*','AFD:*'

[root@rac1 ~]# $ORACLE_HOME/bin/asmcmd dsget

parameter:/dev/asm*, AFD:*

profile:/dev/asm*,AFD:*

4、查看节点信息

[root@rac1 ~]# olsnodes -a

rac1 Hub

rac2 Hub

以下需要在所有节点运行

5、停止crs

[root@rac1 ~]# crsctl stop crs

6、安装oracle afd

节点1、节点2

加载以及配置AFD

[root@rac1 yum.repos.d]# asmcmd afd_configure

备注：在7.4以上的redhat或者centos下需要升级kmod才可以启用AFD，在前面一篇文章中已有介绍

解决在RHEL/CentOS7.4以上版本无法使用AFD(Oracle ASMFD)特性

https://blog.csdn.net/kiral07/article/details/87629679

加载afd过程：

AFD-627: AFD distribution files found.

AFD-634: Removing previous AFD installation.

AFD-635: Previous AFD components successfully removed.

AFD-636: Installing requested AFD software.

AFD-637: Loading installed AFD drivers.

AFD-9321: Creating udev for AFD.

AFD-9323: Creating module dependencies - this may take some time.

AFD-9154: Loading 'oracleafd.ko' driver.

AFD-649: Verifying AFD devices.

AFD-9156: Detecting control device '/dev/oracleafd/admin'.

AFD-638: AFD installation correctness verified.

Modifying resource dependencies - this may take some time.

查询afd状态信息

[root@rac1 yum.repos.d]# asmcmd afd_state

ASMCMD-9526: The AFD state is 'LOADED' and filtering is 'ENABLED' on host 'rac1'

7、启动crs

[root@rac1 yum.repos.d]# crsctl start crs

CRS-4123: Oracle High Availability Services has been started.

8、查看当前存储设备

[root@rac1 yum.repos.d]# ll /dev/mapper/mpath*

lrwxrwxrwx 1 root root 7 Feb 15 17:18 /dev/mapper/mpathc -> ../dm-1

lrwxrwxrwx 1 root root 7 Feb 15 17:18 /dev/mapper/mpathd -> ../dm-0

此处使用多路径设备mpathc、mpathd

[root@rac2 ~]# multipath -ll

mpathd (14f504e46494c45526147693538302d577037452d39596459) dm-1 OPNFILER,VIRTUAL-DISK

size=30G features='0' hwhandler='0' wp=rw

|-+- policy='service-time 0' prio=1 status=active

| `- 34:0:0:1 sdc 8:32 active ready running

|-+- policy='service-time 0' prio=1 status=enabled

| `- 35:0:0:1 sde 8:64 active ready running

|-+- policy='service-time 0' prio=1 status=enabled

| `- 36:0:0:1 sdg 8:96 active ready running

`-+- policy='service-time 0' prio=1 status=enabled

`- 37:0:0:1 sdi 8:128 active ready running

mpathc (14f504e46494c45524f444c7844412d717a557a2d6b7a6752) dm-0 OPNFILER,VIRTUAL-DISK

size=40G features='0' hwhandler='0' wp=rw

|-+- policy='service-time 0' prio=1 status=active

| `- 34:0:0:0 sdb 8:16 active ready running

|-+- policy='service-time 0' prio=1 status=enabled

| `- 35:0:0:0 sdd 8:48 active ready running

|-+- policy='service-time 0' prio=1 status=enabled

| `- 36:0:0:0 sdf 8:80 active ready running

`-+- policy='service-time 0' prio=1 status=enabled

`- 37:0:0:0 sdh 8:112 active ready running

9、添加afd发现路径

切换到grid用户

[root@rac2 ~]# su - grid

使用afd_dsset添加存储路径

[grid@rac2:/home/grid]$asmcmd afd_dsset '/dev/mapper/mpath*'

[grid@rac2:/home/grid]$asmcmd afd_dsget

AFD discovery string: /dev/mapper/mpath*

此时未添加afd label所以为空

[grid@rac2:/home/grid]$asmcmd afd_lsdsk

There are no labelled devices.

至此从步骤5，在rac所有节点已运行所有命令

二、转移UDEV设备到AFD路径

1、查看当前ocr以及voting files磁盘组

[root@rac1 ~]# ocrcheck -config

Oracle Cluster Registry configuration is :

Device/File Name : +CRS

[root@rac1 ~]# crsctl query css votedisk

## STATE File Universal Id File Name Disk group

-- ----- ----------------- --------- ---------

1. ONLINE 4e20265767f54f49bf12bd72f367217f (/dev/asm_crs) [CRS]

Located 1 voting disk(s).

2、查看crs磁盘组对应的udev存储路径

[root@rac1 ~]# su - grid

[grid@rac1:/home/grid]$asmcmd lsdsk -G crs

Path

/dev/asm_crs

3、停止rac集群

[root@rac1 ~]# crsctl stop cluster -all

4、转移udev设备到afd

使用label添加asmcrs磁盘组，将udev规则下的磁盘路径转移到afd

[grid@rac1:/home/grid]$asmcmd afd_label asmcrs /dev/mapper/mpathc --migrate

crs磁盘组已加载完毕

[grid@rac1:/home/grid]$asmcmd afd_lsdsk

--------------------------------------------------------------------------------

Label Filtering Path

================================================================================

ASMCRS ENABLED /dev/mapper/mpathc

备注：由于当前磁盘组已被asm使用，必须使用migrate才可以进行转移。

添加另外一块data磁盘组

[grid@rac1:/home/grid]$asmcmd afd_label asmdata /dev/mapper/mpathd --migrate

查看afd磁盘组，已加载完毕

[grid@rac1:/home/grid]$asmcmd afd_lsdsk

--------------------------------------------------------------------------------

Label Filtering Path

================================================================================

ASMCRS ENABLED /dev/mapper/mpathc

ASMDATA ENABLED /dev/mapper/mpathd

5、在其余节点扫描afd设备

[grid@rac2:/home/grid]$asmcmd afd_scan

[grid@rac2:/home/grid]$asmcmd afd_lsdsk

--------------------------------------------------------------------------------

Label Filtering Path

================================================================================

ASMCRS ENABLED /dev/mapper/mpathc

ASMDATA ENABLED /dev/mapper/mpathd

6、启动rac集群

[root@rac1 ~]# crsctl start cluster -all

7、在asm实例下查询asm磁盘信息

原udev asm存储路径信息还能查看到

[root@rac1 ~]# asmcmd lsdsk

Path

AFD:ASMCRS

AFD:ASMDATA

SQL> col name for a10

SQL> col label for a10

SQL> col path for a15

SQL> select NAME,LABEL,PATH from V$ASM_DISK;

NAME LABEL PATH

---------- ---------- ---------------

ASMDATA /dev/asm_data ---->之前udev asm路径

ASMCRS /dev/asm_crs ---->之前udev asm路径

CRS_0000 ASMCRS AFD:ASMCRS

DATA_0000 ASMDATA AFD:ASMDATA

8、修改发现路径

[grid@rac1:/home/grid]$asmcmd dsget

parameter:/dev/asm*, AFD:*

profile:/dev/asm*,AFD:*

只保留afd路径

[grid@rac1:/home/grid]$asmcmd dsset 'AFD:*'

[grid@rac1:/home/grid]$asmcmd dsget

parameter:AFD:*

profile:AFD:*

再次查询udev路径下的设备已没有

SQL> select NAME,LABEL,PATH from V$ASM_DISK;

NAME LABEL PATH

---------- ---------- ---------------

CRS_0000 ASMCRS AFD:ASMCRS

DATA_0000 ASMDATA AFD:ASMDATA

9、移除UDEV规则文件

[root@rac1 ~]# ll -hrt /etc/udev/rules.d/

total 12K

-rw-r--r-- 1 root root 297 Nov 3 17:04 99-oracle-asmdevices.rules.old

-rw-r--r-- 1 root root 224 Feb 15 17:13 53-afd.rules

-rw-r--r-- 1 root root 957 Feb 18 08:55 70-persistent-ipoib.rules

99-oracle-asmdevices.rules重命名之后已无法发现磁盘

[root@rac1 ~]# ll /dev/asm*

ls: cannot access /dev/asm*: No such file or directory

使用afd特性的磁盘组未受影响

[grid@rac2:/home/grid]$asmcmd afd_lsdsk

--------------------------------------------------------------------------------

Label Filtering Path

================================================================================

ASMCRS ENABLED /dev/mapper/mpathc

ASMDATA ENABLED /dev/mapper/mpathd

到此为止已完成afd的配置与加载

三、ASM磁盘组dd格式化测试

Oracle的afd特性可以过滤掉”非规范“的io操作，只要不是用于oracle的io操作都会被过滤掉，下面使用dd格式化asm整个磁盘组做测试

1、增加一个磁盘组”asmtest“用来做dd格式化实验

[root@rac1 ~]# asmcmd afd_label asmtest /dev/mapper/mpathe

[root@rac1 ~]# asmcmd afd_lsdsk

--------------------------------------------------------------------------------

Label Filtering Path

================================================================================

ASMCRS ENABLED /dev/mapper/mpathc

ASMDATA ENABLED /dev/mapper/mpathd

ASMTEST ENABLED /dev/mapper/mpathe

[root@rac1 ~]# su - grid

[grid@rac1:/home/grid]$sqlplus / as sysasm

创建asmtest磁盘组

SQL> create diskgroup asmtest external redundancy disk 'AFD:asmtest';

Diskgroup created.

2、创建测试表空间asmtest以及测试表

SQL> create tablespace asmtest datafile '+asmtest' size 100m;

SQL> create table afd (id number) tablespace asmtest;

SQL> insert into afd values (1);

1 row created.

SQL> commit;

Commit complete.

SQL> select * from afd;

----------

3、dd格式化

格式化整个磁盘组”asmtest“ —>/dev/mapper/mpathe

[root@rac1 ~]# dd if=/dev/zero of=/dev/mapper/mpathe

dd: writing to dev/mapper/mpathe No space left on device

2097153+0 records in

2097152+0 records out

1073741824 bytes (1.1 GB) copied, 70.6 s, 15.2 MB/s

4、再次做创建表空间操作

SQL> create tablespace asmtest2 datafile '+asmtest' size 100m;

SQL> create table afd2 (id number) tablespace asmtest2;

SQL> insert into afd2 values (2);

1 row created.

SQL> commit;

Commit complete.

SQL> select * from afd;

----------

SQL> ALTER system checkpoint;

System altered.

checkpoint之后也没有报错

5、禁用afd Filter

[root@rac1 ~]# asmcmd afd_filter -d

备注（-d是disable、-e是enable）

[root@rac1 ~]# asmcmd afd_lsdsk

--------------------------------------------------------------------------------

Label Filtering Path

================================================================================

ASMCRS DISABLED /dev/mapper/mpathc

ASMDATA DISABLED /dev/mapper/mpathd

ASMTEST DISABLED /dev/mapper/mpathe

6、再次做dd格式化

[root@rac1 ~]# dd if=/dev/zero of=/dev/mapper/mpathe

dd: writing to dev/mapper/mpathe No space left on device

2097153+0 records in

2097152+0 records out

1073741824 bytes (1.1 GB) copied, 89.2804 s, 12.0 MB/s

7、在数据库中测试

SQL> insert into afd values (3);

1 row created.

SQL> commit;

Commit complete.

SQL> alter system checkpoint;

alter system checkpoint

ERROR at line 1:

ORA-03113: end-of-file on communication channel

Process ID: 21718

Session ID: 35 Serial number: 63358

数据库已崩溃

数据库重启之后已无法启动

[oracle@rac1:/home/oracle]$sqlplus / as sysdba

SQL*Plus: Release 12.2.0.1.0 Production on Mon Feb 18 14:55:41 2019

Connected to an idle instance.

SQL> startup

ORA-39510: CRS error performing start on instance 'orcl1' on 'orcl'

CRS-2672: Attempting to start 'ora.AFDTEST.dg' on 'rac1'

CRS-2672: Attempting to start 'ora.AFDTEST.dg' on 'rac2'

CRS-2674: Start of 'ora.AFDTEST.dg' on 'rac1' failed

CRS-2674: Start of 'ora.AFDTEST.dg' on 'rac2' failed

CRS-0215: Could not start resource 'ora.orcl.db 1 1'.

clsr_start_resource:260 status:215

clsrapi_start_db:start_asmdbs status:215

四、拓展研究

在配置完afd之后，在dev路径下会有lable过后的磁盘

[root@rac1 ~]# ll /dev/oracleafd/disks/

total 8

-rwxrwx--- 1 grid oinstall 19 Feb 18 13:40 ASMCRS

-rwxrwx--- 1 grid oinstall 19 Feb 18 13:40 ASMDATA

查看此设备内容发现对应为多路径设备

[root@rac1 ~]# cat /dev/oracleafd/disks/ASMCRS

/dev/mapper/mpathc

[root@rac1 ~]# cat /dev/oracleafd/disks/ASMDATA

/dev/mapper/mpathd

udev规则下会有afd的规则文件

[grid@rac1:/home/grid]$ll -hrt /etc/udev/rules.d/

total 12K

-rw-r--r-- 1 root root 297 Nov 3 17:04 99-oracle-asmdevices.rules.old

-rw-r--r-- 1 root root 224 Feb 15 17:13 53-afd.rules

-rw-r--r-- 1 root root 957 Feb 18 08:55 70-persistent-ipoib.rules

[grid@rac1:/home/grid]$cat /etc/udev/rules.d/53-afd.rules

# AFD devices

KERNEL=="oracleafd/.*", OWNER="grid", GROUP="asmadmin", MODE="0775"

KERNEL=="oracleafd/*", OWNER="grid", GROUP="asmadmin", MODE="0775"

KERNEL=="oracleafd/disks/*", OWNER="grid", GROUP="asmadmin", MODE="0664"

五、总结

Oracle的afd特性可以将”危险“IO操作进行重定向，具体原理不得而知，其本质还是通过系统内核使用udev规则加载磁盘设备。

Oracle 12C R2-新特性-自动配置ASMFD

1 说明

ASMFD 是 12.1 中就引入的新特性，它可以不用手动配置 ASM 磁盘，更重要的是它可以保护磁盘被其他非 Oracle 操作复写，例如 dd ， echo 等命令。

更为详尽的介绍，请查看官方文档：

--12.1 新特性 ASMFD

在 12.2 中， ASMFD 被加强了，它可以自动配置磁盘，只需要执行一个命令，该磁盘就可以被 ASM 使用。

非常方便。

2 具体例子

2.1 创建目录

[root@rac1 software]# mkdir -p /u01/app/12.2.0/grid[root@rac1 software]# chown grid:oinstall /u01/app/12.2.0/grid

2.2 解压 GRID 软件

使用 grid 用户解压

[grid@rac1 software]# cd /u01/app/12.2.0/grid[grid@rac1 grid]# unzip -q /software/grid_home_image.zip

2.3 配置共享磁盘用于 ASMFD

2.3.1 使用 root 用户登录，并设置 ORACLE_HOME ， ORACLE_BASE

[root@rac1 grid]# su - root[root@rac1 grid]# export ORACLE_HOME=/u01/app/12.2.0/grid[root@rac1 grid]# export ORACLE_BASE=/tmp[root@rac1 grid]# echo $ORACLE_BASE/tmp[root@rac1 grid]# echo $ORACLE_HOME/u01/app/12.2.0/grid

2.3.2 使用 ASMCMD 命令来为 ASMFD 提供磁盘

如下，初始化三块磁盘，就不需要使用 udev ， ASMLIB 等方式来绑定磁盘并赋权限

[root@rac1 grid]# /u01/app/12.2.0/grid/bin/asmcmd afd_label DATA1 /dev/sdb --init[root@rac1 grid]#

2.3.3 验证磁盘是否被标记为 ASMFD 使用

[root@rac1 grid]# /u01/app/12.2.0/grid/bin/asmcmd afd_lslbl /dev/sdb--------------------------------------------------------------------------------Label                     Duplicate  Path====================================DATA1                              /dev/sdb

然后下面安装 GRID 的时候，就可以直接使用该磁盘了 /dev/sdb 。

注意 :/dev/sdb 重启后，可能会变名称，所以 Oracle 使用了 label 标签将其绑定

2.3.4 重置 ORACLE_BASE

unset ORACLE_BASE

2.4 开始安装 GRID

./gridSetup.sh

更多信息，请参考官方文档：

ASMFD (ASM Filter Driver) 支持的操作系统版本

ASMFD 12.1.0.2 Supported Platforms

Vendor	Version	Update/Kernel	Architecture	Bug or PSU
Oracle Linux – RedHat Compatible Kernel	5	Update 3 and later, 2.6.18 kernel series (RedHat Compatible Kernel)	X86_64
Oracle Linux – Unbreakable Enterprise Kernel	5	Update 3 and later, 2.6.39-100 and later UEK 2.6.39 kernels	X86_64	(See Note 1)
Oracle Linux – RedHat Compatible Kernel	6	All Updates, 2.6.32-71 and later 2.6.32 RedHat Compatible kernels	X86_64
Oracle Linux - Unbreakable Enterprise Kernel	6	All Updates, 2.6.39-100 and later UEK 2.6.39 kernels	X86_64	(See Note 1)
Oracle Linux - Unbreakable Enterprise Kernel	6	All Updates, 3.8.13-13 and later UEK 3.8.13 kernels	X86_64
Oracle Linux - Unbreakable Enterprise Kernel	6	All Updates, 4.1.12 and later UEK 4.1.12 kernels	X86_64	12.1.0.2.160719 (Base Bug )
Oracle Linux – RedHat Compatible Kernel	7	Update 0, RedHat Compatible Kernel 3.10.0-123	X86_64	(Base Bug )
Oracle Linux – RedHat Compatible Kernel	7	Update 1 and later, 3.10-0-229 and later RedHat Compatible kernels	X86_64	12.1.0.2.160119 (Base Bug )
Oracle Linux - Unbreakable Enterprise Kernel	7	All Updates, 3.8.13-35 and later UEK 3.8.13 kernels	X86_64	(Base Bug ) Base ( See Note 1 )
Oracle Linux - Unbreakable Enterprise Kernel	7	All Updates, 4.1.12 and later UEK 4.1.12 kernels	X86_64	12.1.0.2.160719 (Base Bug )
RedHat Linux	5	Update 3 and later, 2.6.18 kernel series	X86_64
RedHat Linux	6	All Updates, 2.6.32-279 and later RedHat kernels	X86_64
RedHat Linux	7	Update 0, 3.10.0-123 kernel	X86_64	(Base Bug )
RedHat Linux	7	Update 1 and later, 3.10.0-229 and later RedHat kernels	X86_64	12.1.0.2.160119 (Base Bug )
RedHat Linux	7	Update 4	X86_64	12.1.0.2.170718ACFSPSU + Patch 26247490
Novell SLES	11	SP2	X86_64	Base
Novell SLES	11	SP3	X86_64	Base
Novell SLES	11	SP4	X86_64	12.1.0.2.160419 (Base Bug )
Novell SLES	12	SP1	X86_64	12.1.0.2.170117ACFSPSU(Base Bug )

12c新特性ASMFD

时间: 2016-05-17 22:32:08 | 作者: ohsdba |

如非注明，本站文章皆为原创。欢迎转载，转载时请注明出处和作者信息。

从12.1.0.2开始，Oracle 引入了ASMFD(ASM Filter Driver)，ASMFD只适应于Linux平台。安装完Grid Infrastructure后，你可以决定是否配置她。如果之前使用了ASMLIB(可以简单的理解为对设备做标签来标识磁盘)或者udev(可以动态管理设备)，迁移到ASMFD之后，需要卸载ASMLIB或禁用udev的规则。通过Filter driver可以过滤无效的请求，避免因为非oracle的I/O请求造成意外的覆写，进而保证了系统的安全和稳定。

官方文档中关于ASMFD的描述

This feature is available on Linux systems starting with Oracle Database 12c Release 1 (12.1.0.2).

Oracle ASM Filter Driver (Oracle ASMFD) is a kernel module that resides in the I/O path of the Oracle ASM disks.Oracle ASM uses the filter driver to validate write I/O requests to Oracle ASM disks. After installation of Oracle Grid Infrastructure, you can optionally configure Oracle ASMFD for your system. If ASMLIB is configured for an existing Oracle ASM installation, then you must explicitly migrate the existing ASMLIB configuration to Oracle ASMFD.

The Oracle ASMFD simplifies the configuration and management of disk devices by eliminating the need to rebind disk devices used with Oracle ASM each time the system is restarted.

The Oracle ASM Filter Driver rejects any I/O requests that are invalid. This action eliminates accidental overwrites of Oracle ASM disks that would cause corruption in the disks and files within the disk group. For example, the Oracle ASM Filter Driver filters out all non-Oracle I/Os which could cause accidental overwrites.

ASMFD会拒绝所有的无效的I/O请求。这种行为可以避免因为意外的覆写造成ASM Disk的损坏或磁盘组中文件的损坏。比如她会过滤出所有可能造成覆写的non-oracle的I/O请求。

本文以Oracle Restart(测试版本12.1.0.2.0)环境测试为例来说明如何安装配置ASMFD。首先安装GI(Install Softeware Only)，然后配置ASMFD，配置Label ASMFD Disks，创建ASM实例，创建ASM磁盘组(ASMFD)，创建spfile并迁移至ASM磁盘组。最后在启用和关闭Filter功能情况下分别测试。

详情参考：http://docs.oracle.com/database/121/OSTMG/GUID-06B3337C-07A3-4B3F-B6CD-04F2916C11F6.htm

配置Oracle Restart(SIHA)

[root@db1 ~]# /orgrid/oracle/product/121/root.sh

Performing root user operation.

The following environment variables are set as:

ORACLE_OWNER= orgrid

ORACLE_HOME= /orgrid/oracle/product/121

Enter the full pathname of the local bin directory: [/usr/local/bin]:

The contents of "dbhome" have not changed. No need to overwrite.

The contents of "oraenv" have not changed. No need to overwrite.

The contents of "coraenv" have not changed. No need to overwrite.

Entries will be added to the /etc/oratab file as needed by

Database Configuration Assistant when a database is created

Finished running generic part of root script.

Now product-specific root actions will be performed.

To configure Grid Infrastructure for a Stand-Alone Server run the following command as the root user:

/orgrid/oracle/product/121/perl/bin/perl -I/orgrid/oracle/product/121/perl/lib -I/orgrid/oracle/product/121/crs/install /orgrid/oracle/product/121/crs/install/roothas.pl 执行这个脚本配置HAS，可以不必在GUI下运行

To configure Grid Infrastructure for a Cluster execute the following command as orgrid user:

/orgrid/oracle/product/121/crs/config/config.sh

安装GI，选择只安装软件，如果要配置RAC，需要 运行config.sh脚本( 必须在GUI模式下运行 )，会让你输入cluster信息，scan信息，感兴趣的可以尝试下。

This command launches the Grid Infrastructure Configuration Wizard. The wizard also supports silent operation, and the parameters can be passed through the response file that is available in the installation media.

[root@db1 ~]#

[root@db1 ~]# /orgrid/oracle/product/121/perl/bin/perl -I/orgrid/oracle/product/121/perl/lib -I/orgrid/oracle/product/121/crs/install /orgrid/oracle/product/121/crs/install/roothas.pl

Using configuration parameter file: /orgrid/oracle/product/121/crs/install/crsconfig_params

LOCAL ADD MODE

Creating OCR keys for user 'orgrid', privgrp 'asmadmin'..

Operation successful.

LOCAL ONLY MODE

Successfully accumulated necessary OCR keys.

Creating OCR keys for user 'root', privgrp 'root'..

Operation successful.

CRS-4664: Node db1 successfully pinned.

2016/05/16 22:10:54 CLSRSC-330: Adding Clusterware entries to file 'oracle-ohasd.conf'

db1 2016/05/16 22:11:11 /orgrid/oracle/product/121/cdata/db1/backup_20160516_221111.olr 0

CRS-2791: Starting shutdown of Oracle High Availability Services-managed resources on 'db1'

CRS-2673: Attempting to stop 'ora.evmd' on 'db1'

CRS-2677: Stop of 'ora.evmd' on 'db1' succeeded

CRS-2793: Shutdown of Oracle High Availability Services-managed resources on 'db1' has completed

CRS-4133: Oracle High Availability Services has been stopped.

CRS-4123: Oracle High Availability Services has been started.

2016/05/16 22:12:19 CLSRSC-327: Successfully configured Oracle Restart for a standalone server

用udev绑定，加载并查看

[root@db1 ~]# cd /etc/udev/rules.d/

[root@db1 rules.d]# cat 99-oracle-asmdevices.rules

KERNEL=="sdb1",NAME="asmdisk1",OWNER="orgrid",GROUP="asmadmin",MODE="0660"KERNEL=="sdb2",NAME="asmdisk2",OWNER="orgrid",GROUP="asmadmin",MODE="0660"KERNEL=="sdb3",NAME="asmdisk3",OWNER="orgrid",GROUP="asmadmin",MODE="0660"KERNEL=="sdb4",NAME="asmdisk4",OWNER="orgrid",GROUP="asmadmin",MODE="0660"KERNEL=="sdc1",NAME="asmdisk5",OWNER="orgrid",GROUP="asmadmin",MODE="0660"KERNEL=="sdc2",NAME="asmdisk6",OWNER="orgrid",GROUP="asmadmin",MODE="0660"KERNEL=="sdc3",NAME="asmdisk7",OWNER="orgrid",GROUP="asmadmin",MODE="0660"KERNEL=="sdc4",NAME="asmdisk8",OWNER="orgrid",GROUP="asmadmin",MODE="0660"  [root@db1 rules.d]# [root@db1 rules.d]# udevadm control --reload-rules[root@db1 rules.d]# udevadm trigger[root@db1 rules.d]# ls -l /dev/asmdisk*brw-rw---- 1 orgrid asmadmin 8, 17 May 16 23:03 /dev/asmdisk1brw-rw---- 1 orgrid asmadmin 8, 18 May 16 23:03 /dev/asmdisk2brw-rw---- 1 orgrid asmadmin 8, 19 May 16 23:03 /dev/asmdisk3brw-rw---- 1 orgrid asmadmin 8, 20 May 16 23:03 /dev/asmdisk4brw-rw---- 1 orgrid asmadmin 8, 33 May 16 23:03 /dev/asmdisk5brw-rw---- 1 orgrid asmadmin 8, 34 May 16 23:03 /dev/asmdisk6brw-rw---- 1 orgrid asmadmin 8, 35 May 16 23:03 /dev/asmdisk7brw-rw---- 1 orgrid asmadmin 8, 36 May 16 23:03 /dev/asmdisk8[root@db1 rules.d]#

更多关于udev，请参考

查看ASMFD是否安装

[root@db1 ~]# export ORACLE_HOME=/orgrid/oracle/product/121

[root@db1 ~]# export ORACLE_SID=+ASM

[root@db1 ~]# export PATH=$ORACLE_HOME/bin:$PATH

[root@db1 ~]# $ORACLE_HOME/bin/asmcmd afd_state

Connected to an idle instance.

ASMCMD-9526: The AFD state is 'NOT INSTALLED' and filtering is 'DEFAULT' on host 'db1'

[root@db1 ~]#

安装ASMFD(必须先关掉CRS(RAC)/HAS(SIHA)服务)

[root@db1 ~]# $ORACLE_HOME/bin/asmcmd afd_configureConnected to an idle instance.ASMCMD-9523: command cannot be used when Oracle Clusterware stack is up[root@db1 ~]# crsctl stop hasCRS-2791: Starting shutdown of Oracle High Availability Services-managed resources on 'db1'CRS-2673: Attempting to stop 'ora.evmd' on 'db1'CRS-2677: Stop of 'ora.evmd' on 'db1' succeededCRS-2793: Shutdown of Oracle High Availability Services-managed resources on 'db1' has completedCRS-4133: Oracle High Availability Services has been stopped.[root@db1 ~]# $ORACLE_HOME/bin/asmcmd afd_configureConnected to an idle instance.AFD-627: AFD distribution files found.AFD-636: Installing requested AFD software.AFD-637: Loading installed AFD drivers.AFD-9321: Creating udev for AFD.AFD-9323: Creating module dependencies - this may take some time.AFD-9154: Loading 'oracleafd.ko' driver.AFD-649: Verifying AFD devices.AFD-9156: Detecting control device '/dev/oracleafd/admin'.AFD-638: AFD installation correctness verified.Modifying resource dependencies - this may take some time.[root@db1 ~]#

查看ASMFD详情

[orgrid@db1 ~]$ $ORACLE_HOME/bin/asmcmd afd_state

Connected to an idle instance.

ASMCMD-9526: The AFD state is ' LOADED ' and filtering is 'DEFAULT' on host 'db1'

[root@db1 ~]# /orgrid/oracle/product/121/bin/crsctl start hasCRS-4123: Oracle High Availability Services has been started.[root@db1 ~]#[orgrid@db1 ~]$[orgrid@db1 bin]$ pwd/orgrid/oracle/product/121/bin[orgrid@db1 bin]$ ls -ltr afd*-rwxr-x--- 1 orgrid asmadmin     1000 May 23  2014 afdroot-rwxr-xr-x 1 orgrid asmadmin 72836515 Jul  1  2014 afdboot-rwxr-xr-x 1 orgrid asmadmin   184403 Jul  1  2014 afdtool.bin-rwxr-x--- 1 orgrid asmadmin      766 May 16 23:29 afdload-rwxr-x--- 1 orgrid asmadmin     1254 May 16 23:29 afddriverstate-rwxr-xr-x 1 orgrid asmadmin     2829 May 16 23:29 afdtool

[root@db1 ~]# crsctl stat res -t--------------------------------------------------------------------------------Name           Target  State        Server                   State details       --------------------------------------------------------------------------------Local Resources--------------------------------------------------------------------------------ora.ons               OFFLINE OFFLINE      db1                      STABLE--------------------------------------------------------------------------------Cluster Resources--------------------------------------------------------------------------------ora.cssd      1        OFFLINE OFFLINE                               STABLEora.diskmon      1        OFFLINE OFFLINE                               STABLEora.driver.afd      1        ONLINE  ONLINE       db1                      STABLEora.evmd      1        ONLINE  ONLINE       db1                      STABLE--------------------------------------------------------------------------------[root@db1 ~]#

安装成功后，你看到afd的一些文件，还能看到资源ora.driver.afd

用afd_label标识磁盘

[orgrid@db1 bin]$ $ORACLE_HOME/bin/asmcmd afd_label ASMDISK1 /dev/asmdisk1

Connected to an idle instance.[orgrid@db1 bin]$ $ORACLE_HOME/bin/asmcmd afd_lsdskConnected to an idle instance.--------------------------------------------------------------------------------Label                     Filtering   Path================================================================================ASMDISK1                    ENABLED   /dev/asmdisk1[orgrid@db1 bin]$ $ORACLE_HOME/bin/asmcmd afd_label ASMDISK2 /dev/asmdisk2Connected to an idle instance.[orgrid@db1 bin]$ $ORACLE_HOME/bin/asmcmd afd_lsdskConnected to an idle instance.--------------------------------------------------------------------------------Label                     Filtering   Path================================================================================ASMDISK1                    ENABLED   /dev/asmdisk1ASMDISK2                    ENABLED   /dev/asmdisk2[orgrid@db1 bin]$ asmcmdConnected to an idle instance.ASMCMD> afd_label ASMDISK3 /dev/asmdisk3ASMCMD> afd_lsdsk--------------------------------------------------------------------------------Label                     Filtering   Path================================================================================ASMDISK1                    ENABLED   /dev/asmdisk1ASMDISK2                    ENABLED   /dev/asmdisk2ASMDISK3                    ENABLED   /dev/asmdisk3ASMCMD>

[root@db1 rules.d]# ls -ltr|tail -5-rw-r--r--. 1 root root  789 Mar 10 05:18 70-persistent-cd.rules-rw-r--r--. 1 root root  341 Mar 10 05:25 99-vmware-scsi-udev.rules-rw-r--r--  1 root root  190 May 16 22:11 55-usm.rules-rw-r--r--  1 root root  600 May 16 23:03 99-oracle-asmdevices.rules-rw-r--r--  1 root root  230 May 17 00:31 53-afd.rules[root@db1 rules.d]#[orgrid@db1 rules.d]$ pwd/etc/udev/rules.d[root@db1 rules.d]# cat 53-afd.rules## AFD devicesKERNEL=="oracleafd/.*", OWNER="orgrid", GROUP="asmadmin", MODE="0770"KERNEL=="oracleafd/*", OWNER="orgrid", GROUP="asmadmin", MODE="0770"KERNEL=="oracleafd/disks/*", OWNER="orgrid", GROUP="asmadmin", MODE="0660"[root@db1 rules.d]# cat 55-usm.rules## ADVM devicesKERNEL=="asm/*",      GROUP="asmadmin", MODE="0770"KERNEL=="asm/.*",     GROUP="asmadmin", MODE="0770"## ACFS devicesKERNEL=="ofsctl",     GROUP="asmadmin", MODE="0664"[root@db1 rules.d]#

安装后会看到udev rules下面多了一些文件，实际上ASMFD仍使用了udev

创建ASM实例(也可以通过asmca去创建)

[orgrid@db1 dbs]$ srvctl add asm[orgrid@db1 dbs]$ ps -ef|grep pmonorgrid    42414  36911  0 14:26 pts/2    00:00:00 grep pmon[orgrid@db1 dbs]$ crsctl stat res -t--------------------------------------------------------------------------------Name           Target  State        Server                   State details       --------------------------------------------------------------------------------Local Resources--------------------------------------------------------------------------------ora.asm               OFFLINE OFFLINE      db1                      STABLEora.ons               OFFLINE OFFLINE      db1                      STABLE--------------------------------------------------------------------------------Cluster Resources--------------------------------------------------------------------------------ora.cssd      1        OFFLINE OFFLINE                               STABLEora.diskmon      1        OFFLINE OFFLINE                               STABLEora.driver.afd      1        ONLINE  ONLINE       db1                      STABLEora.evmd      1        ONLINE  ONLINE       db1                      STABLE--------------------------------------------------------------------------------[orgrid@db1 dbs]$[orgrid@db1 ~]$ cat $ORACLE_HOME/dbs/init*.ora*.asm_power_limit=1*.diagnostic_dest='/orgrid/grid_base'*.instance_type='asm'*.large_pool_size=12M*.memory_target=1024M*.remote_login_passwordfile='EXCLUSIVE'[orgrid@db1 ~]$[orgrid@db1 ~]$ ps -ef|grep pmonorgrid    42724  42694  0 14:30 pts/2    00:00:00 grep pmon[orgrid@db1 ~]$ srvctl start asm[orgrid@db1 ~]$ ps -ef|grep pmonorgrid    42807      1  0 14:30 ?        00:00:00 asm_pmon_+ASMorgrid    42888  42694  0 14:31 pts/2    00:00:00 grep pmon[orgrid@db1 ~]$ crsctl stat res -t--------------------------------------------------------------------------------Name           Target  State        Server                   State details       --------------------------------------------------------------------------------Local Resources--------------------------------------------------------------------------------ora.asm               ONLINE  ONLINE       db1                      Started,STABLEora.ons               OFFLINE OFFLINE      db1                      STABLE--------------------------------------------------------------------------------Cluster Resources--------------------------------------------------------------------------------ora.cssd      1        ONLINE  ONLINE       db1                      STABLEora.diskmon      1        OFFLINE OFFLINE                               STABLEora.driver.afd      1        ONLINE  ONLINE       db1                      STABLEora.evmd      1        ONLINE  ONLINE       db1                      STABLE--------------------------------------------------------------------------------[orgrid@db1 ~]$

通过asmca创建DiskGroup

[orgrid@db1 ~]$ asmca -silent -sysAsmPassword oracle -asmsnmpPassword oracle -createDiskGroup -diskString 'AFD:*' -diskGroupName DATA_AFD -disk 'AFD:ASMDISK1' -disk 'AFD:ASMDISK2' -redundancy Normal -au_size 4 -compatible.asm 12.1 -compatible.rdbms 12.1

Disk Group DATA_AFD created successfully.

[orgrid@db1 ~]$

创建spfile并迁移到磁盘组

[orgrid@db1 ~]$ asmcmd spget[orgrid@db1 ~]$[orgrid@db1 ~]$ sqlplus / as sysdbaSQL*Plus: Release 12.1.0.2.0 Production on Tue May 17 15:09:26 2016Copyright (c) 1982, 2014, Oracle.  All rights reserved.Connected to:Oracle Database 12c Enterprise Edition Release 12.1.0.2.0 - 64bit ProductionWith the Automatic Storage Management optionSQL> show parameter spfNAME                                 TYPE        VALUE------------------------------------ ----------- ------------------------------spfile                               stringSQL> create spfile='+DATA_AFD' from pfile;File created.SQL> show parameter spfNAME                                 TYPE        VALUE------------------------------------ ----------- ------------------------------spfile                               stringSQL> exitDisconnected from Oracle Database 12c Enterprise Edition Release 12.1.0.2.0 - 64bit ProductionWith the Automatic Storage Management option[orgrid@db1 ~]$ asmcmd spget+DATA_AFD/ASM/ASMPARAMETERFILE/registry.253.912092995[orgrid@db1 ~]$

备份并移除udev rule文件99-oracle-asmdevices.rules

重命名99-oracle-asmdevices.rules为99-oracle-asmdevices.rules.bak。如果不move 99-oracle-asmdevices.rules文件，下次重启之后，之前ASMFD标识过的磁盘，看不到。

[orgrid@db1 ~]$ asmcmd afd_lsdskThere are no labelled devices.[root@db1 ~]# ls -l /dev/oracleafd/diskstotal 0[root@db1 ~]# ls -l /dev/oracleafd/admin  disks/

设置磁盘Discovery String字符串

ASMCMD> afd_dsgetAFD discovery string:ASMCMD> afd_dsset '/dev/sd*'       --设置ASMFD discovery string为原来物理磁盘的信息ASMCMD> afd_dsgetAFD discovery string: '/dev/sd*'ASMCMD>[orgrid@db1 ~]$ asmcmd afd_dsgetAFD discovery string: '/dev/sd*'[orgrid@db1 ~]$ asmcmd dsget       --设置ASM磁盘组iscovery string为AFD:*     parameter:AFD:*profile:AFD:*[orgrid@db1 ~]$

重启服务器并验证

[root@db1 ~]# ls -l /dev/oracleafd/disks/total 12-rw-r--r-- 1 root root 10 May 17 00:15 ASMDISK1-rw-r--r-- 1 root root 10 May 17 00:15 ASMDISK2-rw-r--r-- 1 root root 10 May 17 00:15 ASMDISK3[root@db1 ~]#ASMCMD> lsdsk  --candidate   PathAFD:ASMDISK2AFD:ASMDISK3ASMCMD> afd_lsdsk--------------------------------------------------------------------------------Label                     Filtering   Path================================================================================ASMDISK1                   DISABLED   /dev/sdb1ASMDISK2                   DISABLED   /dev/sdb2ASMDISK3                   DISABLED   /dev/sdb3ASMCMD>[orgrid@db1 ~]$ ls -l /dev/disk/by-label/total 0lrwxrwxrwx 1 root root 10 May 17 00:30 ASMDISK1 -> ../../sdb1lrwxrwxrwx 1 root root 10 May 17 00:30 ASMDISK2 -> ../../sdb2lrwxrwxrwx 1 root root 10 May 17 00:31 ASMDISK3 -> ../../sdb3[orgrid@db1 ~]$

重启后会发现，ASMFD用的磁盘的属性变成了root权限

启用Filter功能

ASMCMD> help afd_filterafd_filter        Sets the AFD filtering mode on a given disk path.        If the command is executed without specifying a disk path then        filtering is set at node level.ASMCMD>ASMCMD> afd_filter -e /dev/sdb2ASMCMD> afd_lsdsk--------------------------------------------------------------------------------Label                     Filtering   Path================================================================================ASMDISK1                   DISABLED   /dev/sdb1ASMDISK2                   DISABLED   /dev/sdb2ASMDISK3                   DISABLED   /dev/sdb3ASMCMD> afd_filter -eASMCMD> afd_lsdsk--------------------------------------------------------------------------------Label                     Filtering   Path================================================================================ASMDISK1                    ENABLED   /dev/sdb1ASMDISK2                    ENABLED   /dev/sdb2ASMDISK3                    ENABLED   /dev/sdb3ASMCMD>

创建新磁盘组DATA_PGOLD

SQL> create diskgroup DATA_PGOLD external redundancy disk 'AFD:ASMDISK3';

Diskgroup created.

SQL>

[orgrid@db1 ~]$ kfed read AFD:ASMDISK3

kfbh.endian:                          1 ; 0x000: 0x01kfbh.hard:                          130 ; 0x001: 0x82kfbh.type:                            1 ; 0x002: KFBTYP_DISKHEADkfbh.datfmt:                          1 ; 0x003: 0x01kfbh.block.blk:                       0 ; 0x004: blk=0kfbh.block.obj:              2147483648 ; 0x008: disk=0kfbh.check:                   771071217 ; 0x00c: 0x2df59cf1kfbh.fcn.base:                        0 ; 0x010: 0x00000000kfbh.fcn.wrap:                        0 ; 0x014: 0x00000000kfbh.spare1:                          0 ; 0x018: 0x00000000kfbh.spare2:                          0 ; 0x01c: 0x00000000kfdhdb.driver.provstr: ORCLDISKASMDISK3 ; 0x000: length=16kfdhdb.driver.reserved[0]:   1145918273 ; 0x008: 0x444d5341kfdhdb.driver.reserved[1]:    843797321 ; 0x00c: 0x324b5349kfdhdb.driver.reserved[2]:            0 ; 0x010: 0x00000000kfdhdb.driver.reserved[3]:            0 ; 0x014: 0x00000000kfdhdb.driver.reserved[4]:            0 ; 0x018: 0x00000000kfdhdb.driver.reserved[5]:            0 ; 0x01c: 0x00000000kfdhdb.compat:                168820736 ; 0x020: 0x0a100000kfdhdb.dsknum:                        0 ; 0x024: 0x0000kfdhdb.grptyp:                        1 ; 0x026: KFDGTP_EXTERNALkfdhdb.hdrsts:                        3 ; 0x027: KFDHDR_MEMBERkfdhdb.dskname:                ASMDISK3 ; 0x028: length=8kfdhdb.grpname:              DATA_PGOLD ; 0x048: length=10kfdhdb.fgname:                 ASMDISK2 ; 0x068: length=8kfdhdb.capname:                         ; 0x088: length=0kfdhdb.crestmp.hi:             33035808 ; 0x0a8: HOUR=0x0 DAYS=0x11 MNTH=0x5 YEAR=0x7e0kfdhdb.crestmp.lo:           3231790080 ; 0x0ac: USEC=0x0 MSEC=0x4d SECS=0xa MINS=0x30kfdhdb.mntstmp.hi:             33035808 ; 0x0b0: HOUR=0x0 DAYS=0x11 MNTH=0x5 YEAR=0x7e0kfdhdb.mntstmp.lo:           3239631872 ; 0x0b4: USEC=0x0 MSEC=0x237 SECS=0x11 MINS=0x30kfdhdb.secsize:                     512 ; 0x0b8: 0x0200kfdhdb.blksize:                    4096 ; 0x0ba: 0x1000kfdhdb.ausize:                  1048576 ; 0x0bc: 0x00100000kfdhdb.mfact:                    113792 ; 0x0c0: 0x0001bc80kfdhdb.dsksize:                    2055 ; 0x0c4: 0x00000807kfdhdb.pmcnt:                         2 ; 0x0c8: 0x00000002kfdhdb.fstlocn:                       1 ; 0x0cc: 0x00000001kfdhdb.altlocn:                       2 ; 0x0d0: 0x00000002kfdhdb.f1b1locn:                      2 ; 0x0d4: 0x00000002kfdhdb.redomirrors[0]:                0 ; 0x0d8: 0x0000kfdhdb.redomirrors[1]:                0 ; 0x0da: 0x0000kfdhdb.redomirrors[2]:                0 ; 0x0dc: 0x0000kfdhdb.redomirrors[3]:                0 ; 0x0de: 0x0000kfdhdb.dbcompat:              168820736 ; 0x0e0: 0x0a100000kfdhdb.grpstmp.hi:             33035808 ; 0x0e4: HOUR=0x0 DAYS=0x11 MNTH=0x5 YEAR=0x7e0kfdhdb.grpstmp.lo:           3231717376 ; 0x0e8: USEC=0x0 MSEC=0x6 SECS=0xa MINS=0x30

在启用Filter功能下，用dd做测试

[root@db1 log]# dd if=/dev/zero of=/dev/sdb3dd: writing to `/dev/sdb3': No space left on device4209031+0 records in4209030+0 records out2155023360 bytes (2.2 GB) copied, 235.599 s, 9.1 MB/s[root@db1 log]#

[root@db1 ~]# strings -a /dev/sdb3ORCLDISKASMDISK3ASMDISK3DATA_PGOLDASMDISK30        ...省去了一部分ORCLDISKASMDISK3ASMDISK3DATA_PGOLDASMDISK3[root@db1 ~]#[root@db1 ~]#

通过strings查看/dev/sdb3，可以发现，里面的内容并没有被清空

卸载、挂载磁盘组正常

[orgrid@db1 ~]$ asmcmdASMCMD> lsdgState    Type    Rebal  Sector  Block       AU  Total_MB  Free_MB  Req_mir_free_MB  Usable_file_MB  Offline_disks  Voting_files  NameMOUNTED  EXTERN  N         512   4096  1048576      4110     4058                0            4058              0             N  DATA_ADF/MOUNTED  EXTERN  N         512   4096  1048576      2055     1993                0            1993              0             N  DATA_PGOLD/ASMCMD> umount data_pgoldASMCMD> lsdgState    Type    Rebal  Sector  Block       AU  Total_MB  Free_MB  Req_mir_free_MB  Usable_file_MB  Offline_disks  Voting_files  NameMOUNTED  EXTERN  N         512   4096  1048576      4110     4058                0            4058              0             N  DATA_ADF/ASMCMD> mount data_pgoldASMCMD> lsdgState    Type    Rebal  Sector  Block       AU  Total_MB  Free_MB  Req_mir_free_MB  Usable_file_MB  Offline_disks  Voting_files  NameMOUNTED  EXTERN  N         512   4096  1048576      4110     4058                0            4058              0             N  DATA_ADF/MOUNTED  EXTERN  N         512   4096  1048576      2055     1993                0            1993              0             N  DATA_PGOLD/ASMCMD>

/var/log/messages里显示的错误信息

[root@db1 log]# tail -3 messages

May 17 01:10:34 db1 kernel: F 4297082.224/160516171034 flush-8:16[9173]  afd_mkrequest_fn: write IO on ASM managed device (major=8/minor=18)  not supported i=2 start=8418038 seccnt=2  pstart=4209030  pend=8418060May 17 01:10:34 db1 kernel: F 4297082.224/160516171034 flush-8:16[9173]  afd_mkrequest_fn: write IO on ASM managed device (major=8/minor=18)  not supported i=2 start=8418040 seccnt=2  pstart=4209030  pend=8418060May 17 01:10:34 db1 kernel: F 4297082.224/160516171034 flush-8:16[9173]  afd_mkrequest_fn: write IO on ASM managed device (major=8/minor=18)  not supported i=2 s[root@db1 log]#

在关闭Filter功能情况下做测试

ASMCMD> afd_filter -dASMCMD> afd_lsdsk--------------------------------------------------------------------------------Label                     Filtering   Path================================================================================ASMDISK1                   DISABLED   /dev/sdb1ASMDISK2                   DISABLED   /dev/sdb2ASMDISK3                   DISABLED   /dev/sdb3ASMCMD> exit[orgrid@db1 ~]$

备份磁盘的前1024字节并清除，普通用户没权限读

[orgrid@db1 ~]$ dd if=/dev/sdb3 of=block1 bs=1024 count=1dd: opening `/dev/sdb3': Permission denied[orgrid@db1 ~]$ exitlogout[root@db1 ~]# dd if=/dev/sdb3 of=block1 bs=1024 count=11+0 records in1+0 records out1024 bytes (1.0 kB) copied, 0.00236493 s, 433 kB/s[root@db1 ~]# dd if=/dev/zero of=/dev/sdb3 bs=1024 count=11+0 records in1+0 records out1024 bytes (1.0 kB) copied, 0.000458225 s, 2.2 MB/s[root@db1 ~]# su - orgrid

卸载、挂载磁盘组DATA_PGOLD

[orgrid@db1 ~]$ asmcmd

ASMCMD> lsdg

State Type Rebal Sector Block AU Total_MB Free_MB Req_mir_free_MB Usable_file_MB Offline_disks Voting_files Name

MOUNTED EXTERN N 512 4096 1048576 4110 4058 0 4058 0 N DATA_ADF/

MOUNTED EXTERN N 512 4096 1048576 2055 1993 0 1993 0 N DATA_PGOLD/

ASMCMD> umount data_pgold

ASMCMD> mount data_pgold

ORA-15032: not all alterations performed

ORA-15017: diskgroup "DATA_PGOLD" cannot be mounted

ORA-15040: diskgroup is incomplete (DBD ERROR: OCIStmtExecute)

ASMCMD>

可以看出，关闭了Filter功能之后，就会失去保护功能

通过kfed修复

[root@db1 ~]# /orgrid/oracle/product/121/bin/kfed repair /dev/sdb3

[root@db1 ~]# su - orgrid

[orgrid@db1 ~]$ asmcmd

ASMCMD> lsdg

State Type Rebal Sector Block AU Total_MB Free_MB Req_mir_free_MB Usable_file_MB Offline_disks Voting_files Name

MOUNTED EXTERN N 512 4096 1048576 4110 4058 0 4058 0 N DATA_ADF/

ASMCMD> mount data_pgold

ASMCMD> lsdg

State Type Rebal Sector Block AU Total_MB Free_MB Req_mir_free_MB Usable_file_MB Offline_disks Voting_files Name

MOUNTED EXTERN N 512 4096 1048576 4110 4058 0 4058 0 N DATA_ADF/

MOUNTED EXTERN N 512 4096 1048576 2055 1993 0 1993 0 N DATA_PGOLD/

ASMCMD>

通过之前dd备份的块做修复

[root@db1 ~]# dd if=block1 of=/dev/sdb2 bs=1024 count=1 conv=notrunc

1+0 records in

1+0 records out

1024 bytes (1.0 kB) copied, 0.000467297 s, 2.2 MB/s

[root@db1 ~]# su - orgrid

[orgrid@db1 ~]$ asmcmd

ASMCMD> mount data_pgold

ASMCMD> lsdg

State Type Rebal Sector Block AU Total_MB Free_MB Req_mir_free_MB Usable_file_MB Offline_disks Voting_files Name

MOUNTED EXTERN N 512 4096 1048576 4110 4058 0 4058 0 N DATA_ADF/

MOUNTED EXTERN N 512 4096 1048576 2055 1993 0 1993 0 N DATA_PGOLD/

ASMCMD> exit

[orgrid@db1 ~]$

增加AFD DISK，一般用户没权限添加，必须用root用户

ASMCMD> help afd_label

afd_label

To set the given label to the specified disk

ASMCMD>

[orgrid@db1 ~]$ $ORACLE_HOME/bin/asmcmd afd_label ASMDISK4 /dev/sdb4ORA-15227: could not perform label set/clear operationORA-15031: disk specification '/dev/sdb4' matches no disks (DBD ERROR: OCIStmtExecute)ASMCMD-9513: ASM disk label set operation failed.[root@db1 ~]# /orgrid/oracle/product/121/bin/asmcmd afd_label ASMDISK4 /dev/sdb4Connected to an idle instance.[root@db1 ~]#

常见问题和解答

问：运行afd_configure时遇到ASMCMD-9524: AFD configuration failed 'ERROR: OHASD start failed'

答：安装是如果遇到这个错误，需要安装p19035573_121020_Generic.zip，这个patch实际上是一个asmcmdsys.pm文件

问：什么时候用afd_label --migrate

答：如果是从现有DiskGroup迁移到ASMFD，需要加参数--migrate，否则不需要

Reference

Configure ASMFD

http://docs.oracle.com/database/121/OSTMG/GUID-2F5E344F-AFC2-4768-8C00-6F3C56302123.htm#OSTMG95729

http://docs.oracle.com/database/121/OSTMG/GUID-BB2B3A64-4B83-4A6D-816C-6472FAF9B27A.htm#OSTMG95909

Configure in Restart

http://docs.oracle.com/database/121/OSTMG/GUID-06B3337C-07A3-4B3F-B6CD-04F2916C11F6.htm

http://www.ibm.com/developerworks/cn/linux/l-cn-udev/

https://wiki.archlinux.org/index.php/Udev#Setting_static_device_names


ASMFD 12.2.0.1 Supported Platforms

Vendor	Version	Update/Kernel	Architecture	Bug or PSU
Oracle Linux – RedHat Compatible Kernel	6	All Updates, 2.6.32-71 and later 2.6.32 RedHat Compatible kernels	X86_64	Base
Oracle Linux - Unbreakable Enterprise Kernel	6	All Updates, 2.6.39-100 and later UEK 2.6.39 kernels	X86_64	Base
Oracle Linux – Unbreakable Enterprise Kernel	6	All Updates, 3.8.13-13 and later UEK 3.8.13 kernels	X86_64	Base
Oracle Linux – Unbreakable Enterprise Kernel	6	All Updates, 4.1 and later UEK 4.1 kernels	X86_64	Base
Oracle Linux – RedHat Compatible Kernel	7	GA release, 3.10.0-123 and through 3.10.0-513	X86_64	Base
Oracle Linux – RedHat Compatible Kernel	7	Update 3, 3.10.0-514 and later	X86_64	Base + Patch 25078431
Oracle Linux – RedHat Compatible Kernel	7	Update 4, 3.10.0-663 and later RedHat Compatible Kernels	X86_64	12.2.0.1.180116 (Base Bug 26247490)
Oracle Linux – Unbreakable Enterprise Kernel	7	All Updates, 3.8.13-35 and later UEK 3.8.13 kernels	X86_64	Base
Oracle Linux – Unbreakable Enterprise Kernel	7	All Updates, 4.1 and later UEK 4.1 kernels	X86_64	Base
RedHat Linux	6	All Updates, 2.6.32-279 and later RedHat kernels	X86_64	Base
RedHat Linux	7	GA release, 3.10.0-123 and through 3.10.0-513	X86_64	Base
RedHat Linux	7	Update 4, 3.10.0-663 and later RedHat Compatible Kernels	X86_64	12.2.0.1.180116 (Base Bug 26247490)
Novell SLES	12	GA, SP1	X86_64	Base
Solaris	10	Update 10 or later	X86_64 and SPARC64	Base
Solaris	11	Update 10 and later	X86_64 and SPARC64	Base

解决在RHEL/CentOS7.4以上版本无法使用AFD(Oracle ASMFD)特性

在7.4以上的redhat或者centos，配置afd不能配置成功，AFD is not ‘supported’，经过查询MOS资料，发现在7.4以上的redhat内核需要升级”kmod”

1、加载afd

[root@rac1 ~]# asmcmd afd_configure

ASMCMD-9520: AFD is not 'supported' -----仅输出不支持的信息，无法得知具体内容

2、查看afd的支持的内核版本

[root@rac1 ~]# afdroot install

AFD-620: AFD is not supported on this operating system version: '3.10.0-693.el7.x86_64'

[root@rac1 ~]# acfsdriverstate -orahome $ORACLE_HOME supported

ACFS-9459: ADVM/ACFS is not supported on this OS version: '3.10.0-693.el7.x86_64'

ACFS-9201: Not Supported

[root@rac1 ~]# uname -a

Linux rac1 3.10.0-693.el7.x86_64 #1 SMP Thu Jul 6 19:56:57 EDT 2017 x86_64 x86_64 x86_64 GNU/Linux

----查看当前系统内核版本确实不被支持

[root@rac1 ~]# cat /etc/redhat-release

Red Hat Enterprise Linux Server release 7.4 (Maipo)

3、查看kmod版本

[root@rac2 ~]# rpm -qa|grep kmod

kmod-libs-20-15.el7.x86_64

kmod-20-15.el7.x86_64 ----20-15版本

4、升级kmod

[root@rac1 yum.repos.d]# yum install kmod

Loaded plugins: langpacks, product-id, search-disabled-repos, subscription-manager

This system is not registered with an entitlement server. You can use subscription-manager to register.

Local | 3.6 kB 00:00:00

(1/2): Local/group_gz | 166 kB 00:00:00

(2/2): Local/primary_db | 3.1 MB 00:00:00

Resolving Dependencies

--> Running transaction check

---> Package kmod.x86_64 0:20-15.el7 will be updated

---> Package kmod.x86_64 0:20-21.el7 will be an update

--> Finished Dependency Resolution

Dependencies Resolved

=======================================================================================================================

Package Arch Version Repository Size

=======================================================================================================================

Updating:

kmod x86_64 20-21.el7 Local 121 k

Transaction Summary

=======================================================================================================================

Upgrade 1 Package

Total download size: 121 k

Is this ok [y/d/N]: y

Downloading packages:

Running transaction check

Running transaction test

Transaction test succeeded

Running transaction

Warning: RPMDB altered outside of yum.

Updating : kmod-20-21.el7.x86_64 1/2

Cleanup : kmod-20-15.el7.x86_64 2/2

Verifying : kmod-20-21.el7.x86_64 1/2

Verifying : kmod-20-15.el7.x86_64 2/2

Updated:

kmod.x86_64 0:20-21.el7

Complete!

5、再次查看lmod

[grid@rac1:/home/grid]$rpm -qa|grep kmod

kmod-libs-20-15.el7.x86_64

kmod-20-21.el7.x86_64 --->已升级到20-21版本

6、查看afd驱动信息

[root@rac1 yum.repos.d]# acfsdriverstate -orahome $ORACLE_HOME supported

ACFS-9200: Supported 升级kmod之后afd驱动已支持

7、重新安装afd

加载以及配置AFD

[root@rac1 yum.repos.d]# asmcmd afd_configure

加载afd过程：

AFD-627: AFD distribution files found.

AFD-634: Removing previous AFD installation.

AFD-635: Previous AFD components successfully removed.

AFD-636: Installing requested AFD software.

AFD-637: Loading installed AFD drivers.

AFD-9321: Creating udev for AFD.

AFD-9323: Creating module dependencies - this may take some time.

AFD-9154: Loading 'oracleafd.ko' driver.

AFD-649: Verifying AFD devices.

AFD-9156: Detecting control device '/dev/oracleafd/admin'.

AFD-638: AFD installation correctness verified.

Modifying resource dependencies - this may take some time.

查询afd状态信息

[root@rac1 yum.repos.d]# asmcmd afd_state

ASMCMD-9526: The AFD state is 'LOADED' and filtering is 'ENABLED' on host 'rac1'

无任何报错，配置成功

MOS id:2303388.1

ACFS and AFD report “Not Supported” after installing appropriate Oracle Grid Infrastructure Patches on RedHat (文档 ID 2303388.1)

了解KMOD

https://www.linux.org/docs/man8/kmod.html

上述为linux对kmod的一段简单描述，简单意思是KMOD是管理linux内核的一个模块，对于用户来说不会直接使用kmod，而是其他一些系统命令会调用。

进入sbin目录发现kmod被做了软连接，很多系统命令会被重定向

[grid@rac1:/sbin]$pwd

/sbin

[grid@rac1:/sbin]$ls -alt | grep kmod

lrwxrwxrwx 1 root root 11 Feb 15 17:11 insmod -> ../bin/kmod

lrwxrwxrwx 1 root root 11 Feb 15 17:11 lsmod -> ../bin/kmod

lrwxrwxrwx 1 root root 11 Feb 15 17:11 modinfo -> ../bin/kmod

lrwxrwxrwx 1 root root 11 Feb 15 17:11 modprobe -> ../bin/kmod

lrwxrwxrwx 1 root root 11 Feb 15 17:11 rmmod -> ../bin/kmod

lrwxrwxrwx 1 root root 11 Feb 15 17:11 depmod -> ../bin/kmod

Oracle ASM Filter Driver (ASMFD) – New Features for Oracle ASM 12.1.0.2

作者：张乐奕

2014 年 12 月发布

什么是 Oracle ASM Filter Driver (ASMFD)？

简单地说，这是一个可以取代 ASMLIB 和 udev 设置的新功能，并且还增加了 I/O Filter 功能，这也体现在该功能的命名中。ASMFD 目前只在 Linux 操作系统中有效，并且必须要使用最新版的 Oracle ASM 12.1.0.2。在之前，由于 Linux 操作系统对于块设备的发现顺序不定，所以在系统重启以后，无法保证原来的 /dev/sda 还是 sda，所以不能直接使用这样原始的设备名来做 ASM Disk 的 Path，因此出现了 ASMLIB，以 Label 的方式给予设备一个固定的名字，而 ASM 则直接使用这个固定的名字来创建 ASM 磁盘，后来 ASMLIB 必须要 ULN 帐号才可以下载了，于是大家全部转到了 udev 方式，我还因此写了几篇文章来阐述在 Linux 中如何设置 udev rule。比如：

现在 Oracle 推出了 ASMFD，可以一举取代 ASMLIB 和手动设置 udev rules 文件的繁琐，并且最重要的是 I/O Filter 功能。

什么是 I/O Filter 功能？

文档原文如下：

The Oracle ASM Filter Driver rejects any I/O requests that are invalid. This action eliminates accidental overwrites of Oracle ASM disks that would cause corruption in the disks and files within the disk group. For example, the Oracle ASM Filter Driver filters out all non-Oracle I/Os which could cause accidental overwrites.

意思是：该功能可以拒绝所有无效的 I/O 请求，最主要的作用是防止意外覆写 ASM 磁盘的底层盘，在后面的测试中可以看到对于 root 用户的 dd 全盘清零这样的变态操作也都是可以过滤的。

真是不错，那么该怎么启用这个功能呢？

通常我们原先的 ASM 中都应该使用的是 ASMLIB 或者 udev 绑定的设备，这里就直接描述如何将原先的设备名重新命名为新的 AFD 设备名。

--确认目前 ASMFD 模块（以下简称 AFD）的状态，未加载。[grid@dbserver1 ~]$ asmcmd afd_stateASMCMD-9526: The AFD state is 'NOT INSTALLED' and filtering is 'DEFAULT' on host 'dbserver1.vbox.com' --获取当前 ASM 磁盘发现路径，我这里是使用 udev 绑定的名称[grid@dbserver1 ~]$ asmcmd dsgetparameter:/dev/asm*profile:/dev/asm* --设置 ASM 磁盘路径，将新的 Disk String 加入--可以看到在设置该参数时，ASM 会检查现有已经加载的磁盘，如果不在发现路径上，将会报错。[grid@dbserver1 ~]$ asmcmd dsset AFD:*ORA-02097: parameter cannot be modified because specified value is invalidORA-15014: path '/dev/asm-disk7' is not in the discovery set (DBD ERROR: OCIStmtExecute) --因此我们必须将新的路径加在原始路径后面，设置成多种路径，该操作会运行一段时间，视 ASM 磁盘多少而定[grid@dbserver1 ~]$ asmcmd dsset '/dev/asm*','AFD:*' [grid@dbserver1 ~]$ asmcmd dsgetparameter:/dev/asm*, AFD:*profile:/dev/asm*,AFD:* --检查现在 GI 环境中的节点。[grid@dbserver1 ~]$ olsnodes -adbserver1       Hubdbserver2       Hub --以下命令必须在所有 Hub 节点上都运行，可以使用 Rolling 的方式。以下命令有些需要 root 用户，有些需要 grid 用户，请注意 # 或者 $ 不同的提示符表示不同的用户。--先停止crs[root@dbserver1 ~]# crsctl stop crs --作 AFD Configure，实际上这是一个解压程序包，安装，并加载 Driver 的过程，需要消耗一些时间[root@dbserver1 ~]# asmcmd afd_configureConnected to an idle instance.AFD-627: AFD distribution files found.AFD-636: Installing requested AFD software.AFD-637: Loading installed AFD drivers.AFD-9321: Creating udev for AFD.AFD-9323: Creating module dependencies - this may take some time.AFD-9154: Loading 'oracleafd.ko' driver.AFD-649: Verifying AFD devices.AFD-9156: Detecting control device '/dev/oracleafd/admin'.AFD-638: AFD installation correctness verified.Modifying resource dependencies - this may take some time. --结束以后，可以再次检查 AFD 状态，显示已加载。[root@dbserver1 ~]# asmcmd afd_stateConnected to an idle instance.ASMCMD-9526: The AFD state is 'LOADED' and filtering is 'DEFAULT' on host 'dbserver1.vbox.com' --接下来需要设置 AFD 自己的磁盘发现路径了，其实这里很像以前 ASMLIB 的操作。--设置 AFD 磁盘发现路径，必须先启动 CRS，否则将会遇到下面的错误。同时也可以看到这个信息是存储在每个节点自己的 OLR 中，因此必须在所有节点中都设置。[root@dbserver1 ~]# asmcmd afd_dsgetConnected to an idle instance.ASMCMD-9511: failed to obtain required AFD disk string from Oracle Local Repository[root@dbserver1 ~]#[root@dbserver1 ~]# asmcmd afd_dsset '/dev/sd*'Connected to an idle instance.ASMCMD-9512: failed to update AFD disk string in Oracle Local Repository. --启动 CRS[root@dbserver1 ~]# crsctl start crsCRS-4123: Oracle High Availability Services has been started. --此时查看后台的 ASM 告警日志，可以看到加载的磁盘仍然使用的是原始路径。但是也可以看到 libafd 已经成功加载。2014-11-20 17:01:04.545000 +08:00NOTE: Loaded library: /opt/oracle/extapi/64/asm/orcl/1/libafd12.soORACLE_BASE from environment = /u03/app/gridSQL> ALTER DISKGROUP ALL MOUNT /* asm agent call crs *//* {0:9:3} */NOTE: Diskgroup used for Voting files is:  CRSDGDiskgroup with spfile:CRSDGNOTE: Diskgroup used for OCR is:CRSDGNOTE: Diskgroups listed in ASM_DISKGROUP are  DATADGNOTE: cache registered group CRSDG 1/0xB8E8EA0BNOTE: cache began mount (first) of group CRSDG 1/0xB8E8EA0BNOTE: cache registered group DATADG 2/0xB8F8EA0CNOTE: cache began mount (first) of group DATADG 2/0xB8F8EA0CNOTE: Assigning number (1,2) to disk (/dev/asm-disk3)NOTE: Assigning number (1,1) to disk (/dev/asm-disk2)NOTE: Assigning number (1,0) to disk (/dev/asm-disk1)NOTE: Assigning number (1,5) to disk (/dev/asm-disk10)NOTE: Assigning number (1,3) to disk (/dev/asm-disk8)NOTE: Assigning number (1,4) to disk (/dev/asm-disk9)NOTE: Assigning number (2,3) to disk (/dev/asm-disk7)NOTE: Assigning number (2,2) to disk (/dev/asm-disk6)NOTE: Assigning number (2,1) to disk (/dev/asm-disk5)NOTE: Assigning number (2,5) to disk (/dev/asm-disk12)NOTE: Assigning number (2,0) to disk (/dev/asm-disk4)NOTE: Assigning number (2,6) to disk (/dev/asm-disk13)NOTE: Assigning number (2,4) to disk (/dev/asm-disk11) --将 afd_ds 设置为 ASM 磁盘的底层磁盘设备名，这样以后就不再需要手工配置 udev rules 了。[grid@dbserver1 ~]$ asmcmd afd_dsset '/dev/sd*' [grid@dbserver1 ~]$ asmcmd afd_dsgetAFD discovery string: /dev/sd* --我在测试的时候，上面犯了一个错误，将路径设置为了“dev/sd*”，缺少了最开始的根目录。因此此处没有发现任何磁盘，如果你的测试中，这一步已经可以发现磁盘，请告诉我。[grid@dbserver1 ~]$ asmcmd afd_lsdskThere are no labelled devices. --再次提醒，到此为止的所有命令，都必须要在集群环境的所有节点中都执行。--接下来就是将原先的 ASM 磁盘路径从 udev 转到 AFD--先检查现在的磁盘路径[root@dbserver1 ~]# ocrcheck -configOracle Cluster Registry configuration is :         Device/File Name         :     +CRSDG [root@dbserver1 ~]# crsctl query css votedisk##  STATE    File Universal Id                File Name Disk group--  -----    -----------------                --------- --------- 1. ONLINE   4838a0ee7bfa4fbebf8ff9f58642c965 (/dev/asm-disk1) [CRSDG] 2. ONLINE   72057097a36e4f02bfc7b5e23672e4cc (/dev/asm-disk2) [CRSDG] 3. ONLINE   7906e2fb24d24faebf9b82bba6564be3 (/dev/asm-disk3) [CRSDG]Located 3 voting disk(s). [root@dbserver1 ~]# su - grid[grid@dbserver1 ~]$ asmcmd lsdsk -G CRSDGPath/dev/asm-disk1/dev/asm-disk10/dev/asm-disk2/dev/asm-disk3/dev/asm-disk8/dev/asm-disk9 --由于要修改 OCR 所在的磁盘，因此修改之前需要停止 Cluster。[root@dbserver1 ~]# crsctl stop cluster -all --直接修改会报错，因为 /dev/asm-disk1 已经存在在 ASM 中了。[grid@dbserver1 ~]$ asmcmd afd_label asmdisk01 /dev/asm-disk1Connected to an idle instance.ASMCMD-9513: ASM disk label set operation failed.disk /dev/asm-disk1 is already provisioned for ASM --必须要增加 migrate 关键字，才可以成功。[grid@dbserver1 ~]$ asmcmd afd_label asmdisk01 /dev/asm-disk1 --migrateConnected to an idle instance.[grid@dbserver1 ~]$ asmcmd afd_lsdskConnected to an idle instance.--------------------------------------------------------------------------------Label                     Filtering   Path================================================================================ASMDISK01                   ENABLED   /dev/asm-disk1 --在我的测试 ASM 中，一共有 13 块磁盘，因此依次修改。asmcmd afd_label asmdisk01 /dev/asm-disk1 --migrateasmcmd afd_label asmdisk02 /dev/asm-disk2 --migrateasmcmd afd_label asmdisk03 /dev/asm-disk3 --migrateasmcmd afd_label asmdisk04 /dev/asm-disk4 --migrateasmcmd afd_label asmdisk05 /dev/asm-disk5 --migrateasmcmd afd_label asmdisk06 /dev/asm-disk6 --migrateasmcmd afd_label asmdisk07 /dev/asm-disk7 --migrateasmcmd afd_label asmdisk08 /dev/asm-disk8 --migrateasmcmd afd_label asmdisk09 /dev/asm-disk9 --migrateasmcmd afd_label asmdisk10 /dev/asm-disk10 --migrateasmcmd afd_label asmdisk11 /dev/asm-disk11 --migrateasmcmd afd_label asmdisk12 /dev/asm-disk12 --migrateasmcmd afd_label asmdisk13 /dev/asm-disk13 --migrate [grid@dbserver1 ~]$ asmcmd afd_lsdskConnected to an idle instance.--------------------------------------------------------------------------------Label                     Filtering   Path================================================================================ASMDISK01                   ENABLED   /dev/asm-disk1ASMDISK02                   ENABLED   /dev/asm-disk2ASMDISK03                   ENABLED   /dev/asm-disk3ASMDISK04                   ENABLED   /dev/asm-disk4ASMDISK05                   ENABLED   /dev/asm-disk5ASMDISK06                   ENABLED   /dev/asm-disk6ASMDISK07                   ENABLED   /dev/asm-disk7ASMDISK08                   ENABLED   /dev/asm-disk8ASMDISK09                   ENABLED   /dev/asm-disk9ASMDISK10                   ENABLED   /dev/asm-disk10ASMDISK11                   ENABLED   /dev/asm-disk11ASMDISK12                   ENABLED   /dev/asm-disk12ASMDISK13                   ENABLED   /dev/asm-disk13 --在另外的节点中，不再需要作 label，而是直接 scan 即可，这跟使用 ASMLIB 的操作非常相像。[grid@dbserver2 ~]$ asmcmd afd_scanConnected to an idle instance.[grid@dbserver2 ~]$ asmcmd afd_lsdskConnected to an idle instance.--------------------------------------------------------------------------------Label                     Filtering   Path================================================================================ASMDISK12                   ENABLED   /dev/asm-disk12ASMDISK09                   ENABLED   /dev/asm-disk9ASMDISK08                   ENABLED   /dev/asm-disk8ASMDISK11                   ENABLED   /dev/asm-disk11ASMDISK10                   ENABLED   /dev/asm-disk10ASMDISK13                   ENABLED   /dev/asm-disk13ASMDISK01                   ENABLED   /dev/asm-disk1ASMDISK04                   ENABLED   /dev/asm-disk4ASMDISK06                   ENABLED   /dev/asm-disk6ASMDISK07                   ENABLED   /dev/asm-disk7ASMDISK05                   ENABLED   /dev/asm-disk5ASMDISK03                   ENABLED   /dev/asm-disk3ASMDISK02                   ENABLED   /dev/asm-disk2 --重新启动 Cluster[root@dbserver1 ~]# crsctl start cluster -all --可以看到 ASM 告警日志中已经显示开始使用新的名称。关于其中 WARNING 的含义表示目前 AFD 还不支持 Advanced Format 格式的磁盘，普通磁盘格式一个扇区是 512 字节，而高级格式则为 4K 字节。2014-11-20 17:46:16.695000 +08:00* allocate domain 1, invalid = TRUE* instance 2 validates domain 1NOTE: cache began mount (not first) of group CRSDG 1/0x508D0B98NOTE: cache registered group DATADG 2/0x509D0B99* allocate domain 2, invalid = TRUE* instance 2 validates domain 2NOTE: cache began mount (not first) of group DATADG 2/0x509D0B99WARNING: Library 'AFD Library - Generic , version 3 (KABI_V3)' does not support advanced format disksNOTE: Assigning number (1,0) to disk (AFD:ASMDISK01)NOTE: Assigning number (1,1) to disk (AFD:ASMDISK02)NOTE: Assigning number (1,2) to disk (AFD:ASMDISK03)NOTE: Assigning number (1,3) to disk (AFD:ASMDISK08)NOTE: Assigning number (1,4) to disk (AFD:ASMDISK09)NOTE: Assigning number (1,5) to disk (AFD:ASMDISK10)NOTE: Assigning number (2,0) to disk (AFD:ASMDISK04)NOTE: Assigning number (2,1) to disk (AFD:ASMDISK05)NOTE: Assigning number (2,2) to disk (AFD:ASMDISK06)NOTE: Assigning number (2,3) to disk (AFD:ASMDISK07)NOTE: Assigning number (2,4) to disk (AFD:ASMDISK11)NOTE: Assigning number (2,5) to disk (AFD:ASMDISK12)NOTE: Assigning number (2,6) to disk (AFD:ASMDISK13) --检查磁盘加载路径，以及功能全部是 AFD 样式了。[grid@dbserver1 ~]$ asmcmd lsdskPathAFD:ASMDISK01AFD:ASMDISK02AFD:ASMDISK03AFD:ASMDISK04AFD:ASMDISK05AFD:ASMDISK06AFD:ASMDISK07AFD:ASMDISK08AFD:ASMDISK09AFD:ASMDISK10AFD:ASMDISK11AFD:ASMDISK12AFD:ASMDISK13 --但是我们可以看到在数据字典中仍然存在之前的磁盘路径。SQL> select NAME,LABEL,PATH from V$ASM_DISK; NAME                 LABEL                           PATH-------------------- ------------------------------- ---------------------------------------------                                                     /dev/asm-disk7                                                     /dev/asm-disk6                                                     /dev/asm-disk13                                                     /dev/asm-disk12                                                     /dev/asm-disk11                                                     /dev/asm-disk4                                                     /dev/asm-disk2                                                     /dev/asm-disk9                                                     /dev/asm-disk3                                                     /dev/asm-disk5                                                     /dev/asm-disk10                                                     /dev/asm-disk8                                                     /dev/asm-disk1CRSDG_0000           ASMDISK01                       AFD:ASMDISK01CRSDG_0001           ASMDISK02                       AFD:ASMDISK02CRSDG_0002           ASMDISK03                       AFD:ASMDISK03DATADG_0000          ASMDISK04                       AFD:ASMDISK04DATADG_0001          ASMDISK05                       AFD:ASMDISK05DATADG_0002          ASMDISK06                       AFD:ASMDISK06DATADG_0003          ASMDISK07                       AFD:ASMDISK07CRSDG_0003           ASMDISK08                       AFD:ASMDISK08CRSDG_0004           ASMDISK09                       AFD:ASMDISK09CRSDG_0005           ASMDISK10                       AFD:ASMDISK10DATADG_0004          ASMDISK11                       AFD:ASMDISK11DATADG_0005          ASMDISK12                       AFD:ASMDISK12DATADG_0006          ASMDISK13                       AFD:ASMDISK13 26 rows selected. --需要将 ASM 磁盘发现路径（注意，这跟设置 AFD 磁盘发现路径不是一个命令）中原先的路径去除，只保留 AFD 路径。[grid@dbserver1 ~]$ asmcmd dsset 'AFD:*'[grid@dbserver1 ~]$ asmcmd dsgetparameter:AFD:*profile:AFD:* --再次重启 ASM，一切正常了。SQL> select NAME,LABEL,PATH from V$ASM_DISK; NAME                 LABEL                           PATH-------------------- ------------------------------- -------------------------------------------------------CRSDG_0000           ASMDISK01                       AFD:ASMDISK01CRSDG_0001           ASMDISK02                       AFD:ASMDISK02CRSDG_0002           ASMDISK03                       AFD:ASMDISK03DATADG_0000          ASMDISK04                       AFD:ASMDISK04DATADG_0001          ASMDISK05                       AFD:ASMDISK05DATADG_0002          ASMDISK06                       AFD:ASMDISK06DATADG_0003          ASMDISK07                       AFD:ASMDISK07CRSDG_0003           ASMDISK08                       AFD:ASMDISK08CRSDG_0004           ASMDISK09                       AFD:ASMDISK09CRSDG_0005           ASMDISK10                       AFD:ASMDISK10DATADG_0004          ASMDISK11                       AFD:ASMDISK11DATADG_0005          ASMDISK12                       AFD:ASMDISK12DATADG_0006          ASMDISK13                       AFD:ASMDISK13 13 rows selected. --收尾工作，将原先的 udev rules 文件移除。当然，这要在所有节点中都运行。以后如果服务器再次重启，AFD 就会完全接管了。[root@dbserver1 ~]# mv /etc/udev/rules.d/99-oracle-asmdevices.rules ~oracle/

还有什么发现？

其实，AFD 也在使用 udev。囧。

[grid@dbserver1 ~]$ cat /etc/udev/rules.d/53-afd.rules## AFD devicesKERNEL=="oracleafd/.*", OWNER="grid", GROUP="asmdba", MODE="0770"KERNEL=="oracleafd/*", OWNER="grid", GROUP="asmdba", MODE="0770"KERNEL=="oracleafd/disks/*", OWNER="grid", GROUP="asmdba", MODE="0660"

Label 过后的磁盘在 /dev/oracleafd/disks 目录中可以找到。

[root@dbserver2 disks]# ls -l /dev/oracleafd/diskstotal 52-rw-r--r-- 1 root root 9 Nov 20 18:52 ASMDISK01-rw-r--r-- 1 root root 9 Nov 20 18:52 ASMDISK02-rw-r--r-- 1 root root 9 Nov 20 18:52 ASMDISK03-rw-r--r-- 1 root root 9 Nov 20 18:52 ASMDISK04-rw-r--r-- 1 root root 9 Nov 20 18:52 ASMDISK05-rw-r--r-- 1 root root 9 Nov 20 18:52 ASMDISK06-rw-r--r-- 1 root root 9 Nov 20 18:52 ASMDISK07-rw-r--r-- 1 root root 9 Nov 20 18:52 ASMDISK08-rw-r--r-- 1 root root 9 Nov 20 18:52 ASMDISK09-rw-r--r-- 1 root root 9 Nov 20 18:52 ASMDISK10-rw-r--r-- 1 root root 9 Nov 20 18:52 ASMDISK11-rw-r--r-- 1 root root 9 Nov 20 18:52 ASMDISK12-rw-r--r-- 1 root root 9 Nov 20 18:52 ASMDISK13

这里有一个很大不同，所有磁盘的属主变成了 root，并且只有 root 才有写入的权限。很多文章认为，这就是 AFD 的 filter 功能体现了，因为现在用 oracle 或者 grid 用户都没有办法直接对 ASM 磁盘进行写入操作，自然就获得了一层保护。比如以下命令会直接报权限不足。

[oracle@dbserver1 disks]$ echo "do some evil" > ASMDISK99-bash: ASMDISK99: Permission denied

但是如果你认为这就是 AFD 的保护功能，那也太小看 Oracle 了，仅仅是这样也对不起名字中 Filter 字样。且看后面分解。

操作系统中也可以看到 AFD 磁盘和底层磁盘的对应关系。

[grid@dbserver1 /]$ ls -l /dev/disk/by-label/total 0lrwxrwxrwx 1 root root 9 Nov 20 19:17 ASMDISK01 -> ../../sdclrwxrwxrwx 1 root root 9 Nov 20 19:17 ASMDISK02 -> ../../sddlrwxrwxrwx 1 root root 9 Nov 20 19:17 ASMDISK03 -> ../../sdelrwxrwxrwx 1 root root 9 Nov 20 19:17 ASMDISK04 -> ../../sdflrwxrwxrwx 1 root root 9 Nov 20 19:17 ASMDISK05 -> ../../sdglrwxrwxrwx 1 root root 9 Nov 20 19:17 ASMDISK06 -> ../../sdhlrwxrwxrwx 1 root root 9 Nov 20 19:17 ASMDISK07 -> ../../sdilrwxrwxrwx 1 root root 9 Nov 20 19:17 ASMDISK08 -> ../../sdjlrwxrwxrwx 1 root root 9 Nov 20 19:17 ASMDISK09 -> ../../sdklrwxrwxrwx 1 root root 9 Nov 20 19:17 ASMDISK10 -> ../../sdllrwxrwxrwx 1 root root 9 Nov 20 19:17 ASMDISK11 -> ../../sdmlrwxrwxrwx 1 root root 9 Nov 20 19:17 ASMDISK12 -> ../../sdnlrwxrwxrwx 1 root root 9 Nov 20 19:17 ASMDISK13 -> ../../sdo

再次重启服务器以后，afd_lsdsk 的结果中显示的路径都已经变为底层磁盘，但是 Filtering 却变成了 DISABLED。不要在意这里的 Label 和 Path 的对应和上面的不一样，因为有些是在节点 1 中执行的结果，有些是在节点 2 中执行的结果，而这也是 AFD 功能的展示，不管两边机器发现块设备的顺序是不是一样，只要绑定了 AFD 的 Label，就没问题了。

ASMCMD> afd_lsdsk--------------------------------------------------------------------------------Label                     Filtering   Path================================================================================ASMDISK01                  DISABLED   /dev/sddASMDISK02                  DISABLED   /dev/sdeASMDISK03                  DISABLED   /dev/sdfASMDISK04                  DISABLED   /dev/sdgASMDISK05                  DISABLED   /dev/sdhASMDISK06                  DISABLED   /dev/sdiASMDISK07                  DISABLED   /dev/sdjASMDISK08                  DISABLED   /dev/sdkASMDISK09                  DISABLED   /dev/sdlASMDISK10                  DISABLED   /dev/sdmASMDISK11                  DISABLED   /dev/sdnASMDISK12                  DISABLED   /dev/sdoASMDISK13                  DISABLED   /dev/sdp

最后，该来测试一下 I/O Filter 功能了吧，等好久了！

对，这才是重点。

先看一下如何启用或者禁用 Filter 功能。在我的测试中，单独设置某块盘启用还是禁用是不生效的，只能全局启用或者禁用。

[grid@dbserver1 ~]$ asmcmd help afd_filterafd_filter        Sets the AFD filtering mode on a given disk path.        If the command is executed without specifying a disk path then        filtering is set at node level. Synopsis        afd_filter {-e | -d } [<disk-path>] Description        The options for afd_filter are described below         -e      -  enable  AFD filtering mode        -d      -  disable AFD filtering mode Examples        The following example uses afd_filter to enable AFD filtering        on a given diskpath.         ASMCMD [+] >afd_filter -e /dev/sdq See Also       afd_lsdsk afd_state

启用 Filter 功能。

[grid@dbserver1 ~]$ asmcmd afd_filter -e[grid@dbserver1 ~]$ asmcmd afd_lsdskConnected to an idle instance.--------------------------------------------------------------------------------Label                     Filtering   Path================================================================================ASMDISK01                   ENABLED   /dev/sdbASMDISK02                   ENABLED   /dev/sdcASMDISK03                   ENABLED   /dev/sddASMDISK04                   ENABLED   /dev/sdeASMDISK05                   ENABLED   /dev/sdfASMDISK06                   ENABLED   /dev/sdgASMDISK07                   ENABLED   /dev/sdhASMDISK08                   ENABLED   /dev/sdiASMDISK09                   ENABLED   /dev/sdjASMDISK10                   ENABLED   /dev/sdkASMDISK11                   ENABLED   /dev/sdlASMDISK12                   ENABLED   /dev/sdmASMDISK13                   ENABLED   /dev/sdn

为了以防万一，不破坏我自己的实验环境，增加了一块磁盘来作测试。

[root@dbserver1 ~]# asmcmd afd_label asmdisk99 /dev/sdoConnected to an idle instance.[root@dbserver1 ~]# asmcmd afd_lsdskConnected to an idle instance.--------------------------------------------------------------------------------Label                     Filtering   Path================================================================================ASMDISK01                   ENABLED   /dev/sdbASMDISK02                   ENABLED   /dev/sdcASMDISK03                   ENABLED   /dev/sddASMDISK04                   ENABLED   /dev/sdeASMDISK05                   ENABLED   /dev/sdfASMDISK06                   ENABLED   /dev/sdgASMDISK07                   ENABLED   /dev/sdhASMDISK08                   ENABLED   /dev/sdiASMDISK09                   ENABLED   /dev/sdjASMDISK10                   ENABLED   /dev/sdkASMDISK11                   ENABLED   /dev/sdlASMDISK12                   ENABLED   /dev/sdmASMDISK13                   ENABLED   /dev/sdnASMDISK99                   ENABLED   /dev/sdo

创建一个新的磁盘组。

[grid@dbserver1 ~]$ sqlplus / AS sysasmSQL> CREATE diskgroup DGTEST external redundancy disk 'AFD:ASMDISK99'; Diskgroup created.

先用 KFED 读取一下磁盘头，验证一下确实无误。

[grid@dbserver1 ~]$ kfed read AFD:ASMDISK99kfbh.endian:                          1 ; 0x000: 0x01kfbh.hard:                          130 ; 0x001: 0x82kfbh.type:                            1 ; 0x002: KFBTYP_DISKHEADkfbh.datfmt:                          1 ; 0x003: 0x01kfbh.block.blk:                       0 ; 0x004: blk=0kfbh.block.obj:              2147483648 ; 0x008: disk=0kfbh.check:                  1854585587 ; 0x00c: 0x6e8abaf3kfbh.fcn.base:                        0 ; 0x010: 0x00000000kfbh.fcn.wrap:                        0 ; 0x014: 0x00000000kfbh.spare1:                          0 ; 0x018: 0x00000000kfbh.spare2:                          0 ; 0x01c: 0x00000000kfdhdb.driver.provstr:ORCLDISKASMDISK99 ; 0x000: length=17kfdhdb.driver.reserved[0]:   1145918273 ; 0x008: 0x444d5341kfdhdb.driver.reserved[1]:    961237833 ; 0x00c: 0x394b5349kfdhdb.driver.reserved[2]:           57 ; 0x010: 0x00000039kfdhdb.driver.reserved[3]:            0 ; 0x014: 0x00000000kfdhdb.driver.reserved[4]:            0 ; 0x018: 0x00000000kfdhdb.driver.reserved[5]:            0 ; 0x01c: 0x00000000kfdhdb.compat:                168820736 ; 0x020: 0x0a100000kfdhdb.dsknum:                        0 ; 0x024: 0x0000kfdhdb.grptyp:                        1 ; 0x026: KFDGTP_EXTERNALkfdhdb.hdrsts:                        3 ; 0x027: KFDHDR_MEMBERkfdhdb.dskname:               ASMDISK99 ; 0x028: length=9kfdhdb.grpname:                  DGTEST ; 0x048: length=6kfdhdb.fgname:                ASMDISK99 ; 0x068: length=9

直接使用 dd 尝试将整个磁盘清零。 dd 命令本身没有任何错误返回。

[root@dbserver1 ~]# dd if=/dev/zero of=/dev/sdodd: writing to `/dev/sdo': No space left on device409601+0 records in409600+0 records out209715200 bytes (210 MB) copied, 19.9602 s, 10.5 MB/s

之后重新 mount 磁盘组，如果磁盘被清零，在重新 mount 的时候一定会出现错误，而现在正常挂载。

SQL>  ALTER diskgroup DGTEST dismount; Diskgroup altered. SQL>  ALTER diskgroup DGTEST mount; Diskgroup altered.

觉得不过瘾？那再创建一个表空间，插入一些数据，做一次 checkpoint，仍然一切正常。

SQL> CREATE tablespace test datafile '+DGTEST' SIZE 100M; Tablespace created. SQL> CREATE TABLE t_afd (n NUMBER) tablespace test; TABLE created. SQL> INSERT INTO t_afd VALUES(1); 1 ROW created. SQL> commit; Commit complete. SQL> ALTER system checkpoint; System altered. SQL> SELECT COUNT(*) FROM t_afd;   COUNT(*)----------         1

但是诡异的是，这时候在操作系统级别直接去读取 /dev/sdo 的内容，会显示全部都已经被清空为 0 了。

[root@dbserver1 ~]# od -c -N 256 /dev/sdo0000000  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0*0000400

使用 strings 命令也完全看不到任何有意义的字符。

[root@dbserver1 disks]# strings /dev/sdo[root@dbserver1 disks]#

但是，千万不要被这样的假象迷惑，以为磁盘真的被清空了，在 dd 的时候，/var/log/message 会产生大量日志，明确表示这些在 ASM 管理的设备上的 IO 操作都是不被支持，这才是 Filter 真正起作用的场合。

afd_mkrequest_fn: write IO on ASM managed device (major=8/minor=224)  not supported

使用 kfed ，仍然可以读取到正常的信息。

[grid@dbserver1 ~]$ kfed read AFD:ASMDISK99kfbh.endian:                          1 ; 0x000: 0x01kfbh.hard:                          130 ; 0x001: 0x82kfbh.type:                            1 ; 0x002: KFBTYP_DISKHEADkfbh.datfmt:                          1 ; 0x003: 0x01kfbh.block.blk:                       0 ; 0x004: blk=0kfbh.block.obj:              2147483648 ; 0x008: disk=0kfbh.check:                  1854585587 ; 0x00c: 0x6e8abaf3kfbh.fcn.base:                        0 ; 0x010: 0x00000000kfbh.fcn.wrap:                        0 ; 0x014: 0x00000000kfbh.spare1:                          0 ; 0x018: 0x00000000kfbh.spare2:                          0 ; 0x01c: 0x00000000kfdhdb.driver.provstr:ORCLDISKASMDISK99 ; 0x000: length=17......

直到重新启动服务器（重新启动 ASM，重新启动 Cluster，在操作系统仍然看到的是清零后的数据），所有的数据又回来了。目前还不确认 Oracle 是使用了怎样的重定向技术实现了这样的神奇效果。

[root@dbserver1 ~]# od -c -N 256 /dev/sdo0000000 001 202 001 001  \0  \0  \0  \0  \0  \0  \0 200   u 177   D   I0000020  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \00000040   O   R   C   L   D   I   S   K   A   S   M   D   I   S   K   90000060   9  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \00000100  \0  \0 020  \n  \0  \0 001 003   A   S   M   D   I   S   K   90000120   9  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \00000140  \0  \0  \0  \0  \0  \0  \0  \0   D   G   T   E   S   T  \0  \00000160  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \00000200  \0  \0  \0  \0  \0  \0  \0  \0   A   S   M   D   I   S   K   90000220   9  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \00000240  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0*0000300  \0  \0  \0  \0  \0  \0  \0  \0 022 257 367 001  \0   X  \0 2470000320 022 257 367 001  \0   h 036 344  \0 002  \0 020  \0  \0 020  \00000340 200 274 001  \0 310  \0  \0  \0 002  \0  \0  \0 001  \0  \0  \00000360 002  \0  \0  \0 002  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \00000400[root@dbserver1 ~]# [root@dbserver1 ~]# strings /dev/sdo | grep ASMORCLDISKASMDISK99ASMDISK99ASMDISK99ORCLDISKASMDISK99ASMDISK99ASMDISK99ASMDISK99ASMDISK99ASMPARAMETERFILEASMPARAMETERBAKFILEASM_STALE

最后将 Filter 禁用之后再测试。

[root@dbserver1 ~]# asmcmd afd_filter -dConnected to an idle instance.[root@dbserver1 ~]# asmcmd afd_lsdskConnected to an idle instance.--------------------------------------------------------------------------------Label                     Filtering   Path================================================================================ASMDISK01                  DISABLED   /dev/sdbASMDISK02                  DISABLED   /dev/sdcASMDISK03                  DISABLED   /dev/sddASMDISK04                  DISABLED   /dev/sdeASMDISK05                  DISABLED   /dev/sdfASMDISK06                  DISABLED   /dev/sdgASMDISK07                  DISABLED   /dev/sdhASMDISK08                  DISABLED   /dev/sdiASMDISK09                  DISABLED   /dev/sdjASMDISK10                  DISABLED   /dev/sdkASMDISK11                  DISABLED   /dev/sdlASMDISK12                  DISABLED   /dev/sdmASMDISK13                  DISABLED   /dev/sdnASMDISK99                  DISABLED   /dev/sdo

同样使用 dd 命令清零整个磁盘。

[root@dbserver1 ~]# dd if=/dev/zero of=/dev/sdodd: writing to `/dev/sdo': No space left on device409601+0 records in409600+0 records out209715200 bytes (210 MB) copied, 4.46444 s, 47.0 MB/s

重新 mount 磁盘组，如期报错，磁盘组无法加载。

SQL> alter diskgroup DGTEST dismount; Diskgroup altered. SQL> alter diskgroup DGTEST mount;alter diskgroup DGTEST mount*ERROR at line 1:ORA-15032: not all alterations performedORA-15017: diskgroup "DGTEST" cannot be mountedORA-15040: diskgroup is incomplete

重新启动数据库，也会发现由于表空间中数据库不存在而导致数据库无法正常 Open。

SQL> startupORACLE instance started. Total System Global Area  838860800 bytesFixed SIZE                  2929936 bytesVariable >SIZE             385878768 bytesDATABASE Buffers          226492416 bytesRedo Buffers                5455872 bytesIn-Memory Area            218103808 bytesDATABASE mounted.ORA-01157: cannot identify/LOCK DATA file 15 - see DBWR trace fileORA-01110: DATA file 15: '+DGTEST/CDB12C/DATAFILE/test.256.864163075'

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