oracle中如何解决asm磁盘添加失败问题

蜗牛互联网技术资讯2021-12-174030

这篇文章将为大家详细讲解有关oracle中如何解决asm磁盘添加失败问题，小编觉得挺实用的，因此分享给大家做个参考，希望大家阅读完这篇文章后可以有所收获。

生产环境存储划盘并做了多路径聚合，由于经验生疏忘记需要配置udev。
在添加磁盘到diskgroup时，数据库报错权限不足，简单以为只是对应的字符设备的权限是root:disk导致无法添加到diskgroup。
所以尝试使用chown命令在两个节点将该字符设备修改权限为grid:oinstall后，由于suse系统udev内部机制问题，在添加该字符设备到diskgroup过程中，字符设备的权限自动由grid:oinstall变为root:disk，导致添加磁盘失败。此时该磁盘盘头已写入部分信息，HEADER_STATUS为NUMBER，导致无法重新添加到diskgroup，也无法从磁盘组踢出，进退两难。
由于是生产环境，不敢随意操作，故在测试环境模拟问题并解决。

问题重现：
1 确认/dev/raw/raw6的HEADER_STATUS是CANDIDATE状态，说明可以添加到asm磁盘组。
SQL> select PATH,NAME,DISK_NUMBER,GROUP_NUMBER,STATE,MOUNT_STATUS,HEADER_STATUS,MODE_STATUS from v$asm_disk;
PATH                   NAME            DISK_NUMBER GROUP_NUMBER STATE          MOUNT_STATUS   HEADER_STATUS          MODE_STATUS
------------------------------ -------------------- ----------- ------------ ---------------- -------------- ------------------------ --------------
/dev/raw/raw6                              0        0 NORMAL          CLOSED         CANDIDATE              ONLINE
/dev/raw/raw1               DATA_0000              0        2 NORMAL          CACHED         MEMBER              ONLINE
/dev/raw/raw3               DATA_0002              2        2 NORMAL          CACHED         MEMBER              ONLINE
/dev/raw/raw4               DATA1_0000              0        1 NORMAL          CACHED         MEMBER              ONLINE
/dev/raw/raw5               DATA1_0001              1        1 NORMAL          CACHED         MEMBER              ONLINE
/dev/raw/raw2               DATA_0001              1        2 NORMAL          CACHED         MEMBER              ONLINE
2 查看磁盘组，模拟将/dev/raw/raw6加进磁盘组DATA。
SQL> select GROUP_NUMBER,NAME from v$asm_diskgroup;

GROUP_NUMBER NAME
------------ --------------------
       1 DATA1
       2 DATA
3 将/dev/raw/raw6加入磁盘组DATA的过程中（约等待3s），另开窗口，将/dev/raw/raw6的权限由grid:asmadmin改为root:disk，此时报错如下：
SQL> alter diskgroup DATA add disk '/dev/raw/raw6';
alter diskgroup DATA add disk '/dev/raw/raw6'
*
ERROR at line 1:
ORA-15032: not all alterations performed
ORA-15075: disk(s) are not visible cluster-wide
4 重启udev（即：将/dev/raw/raw6 权限重新改为grid:asmadmin）并重新查询。
SQL> select PATH,NAME,DISK_NUMBER,GROUP_NUMBER,STATE,MOUNT_STATUS,HEADER_STATUS,MODE_STATUS from v$asm_disk;
PATH                   NAME            DISK_NUMBER GROUP_NUMBER STATE          MOUNT_STATUS   HEADER_STATUS          MODE_STATUS
------------------------------ -------------------- ----------- ------------ ---------------- -------------- ------------------------ --------------
/dev/raw/raw6                              0        0 NORMAL          CLOSED         MEMBER              ONLINE
/dev/raw/raw1               DATA_0000              0        2 NORMAL          CACHED         MEMBER              ONLINE
/dev/raw/raw3               DATA_0002              2        2 NORMAL          CACHED         MEMBER              ONLINE
/dev/raw/raw4               DATA1_0000              0        1 NORMAL          CACHED         MEMBER              ONLINE
/dev/raw/raw5               DATA1_0001              1        1 NORMAL          CACHED         MEMBER              ONLINE
/dev/raw/raw2               DATA_0001              1        2 NORMAL          CACHED         MEMBER              ONLINE
5 此时尝试再次将/dev/raw/raw6加入DATA中，出现报错，模拟故障成功。
SQL> alter diskgroup DATA add disk '/dev/raw/raw6';
alter diskgroup DATA add disk '/dev/raw/raw6'
*
ERROR at line 1:
ORA-15032: not all alterations performed
ORA-15033: disk '/dev/raw/raw6' belongs to diskgroup "DATA"

解决方法：
查了oracle官方文档，提供了如下三种解决方法（1453285.1）：
方法一：
    1 备份问题磁盘
        dd if=/dev/oracleasm/disks/EMCORA43 of=/tmp/EMCORA43.txt bs=1M count=10
    2 修改磁盘权限
        chmod 000 /dev/oracleasm/disks/EMCORA47
    3 重新挂载diskgroup，确认diskgroup可以正常挂载，则可以使用dd命令清除盘头信息，并重新添加该磁盘。
        dd if=/dev/zero of=/dev/oracleasm/disks/EMCORA43 bs=1M count=1
方法二：
    使用oracleasm删除磁盘
        /etc/init.d/oracleasm deletedisk EMCORA43
方法三：
    使用force选项强制重新挂载该磁盘。
        alter diskgroup XXXX add disk '/dev/oracleasm/disks/EMCORA43' force;

本次实验采用第三种方法：
具体如下：
SQL>     select NAME, TOTAL_MB, FREE_MB, (TOTAL_MB - FREE_MB) USED_MB, to_char((TOTAL_MB - FREE_MB) * 100 / TOTAL_MB,'99.99') || '%' USED_PRECENT from v$asm_diskgroup;

NAME               TOTAL_MB    FREE_MB    USED_MB USED_PRECENT
-------------------- ---------- ---------- ---------- --------------
DATA1               1998       1901       97   4.85%
DATA               2997        630   2367 78.98%

SQL> select PATH,NAME,DISK_NUMBER,GROUP_NUMBER,STATE,MOUNT_STATUS,HEADER_STATUS,MODE_STATUS from v$asm_disk;

PATH                   NAME            DISK_NUMBER GROUP_NUMBER STATE          MOUNT_STATUS   HEADER_STATUS          MODE_STATUS
------------------------------ -------------------- ----------- ------------ ---------------- -------------- ------------------------ --------------
/dev/raw/raw6                              0        0 NORMAL          CLOSED         MEMBER              ONLINE
/dev/raw/raw1               DATA_0000              0        2 NORMAL          CACHED         MEMBER              ONLINE
/dev/raw/raw3               DATA_0002              2        2 NORMAL          CACHED         MEMBER              ONLINE
/dev/raw/raw4               DATA1_0000              0        1 NORMAL          CACHED         MEMBER              ONLINE
/dev/raw/raw5               DATA1_0001              1        1 NORMAL          CACHED         MEMBER              ONLINE
/dev/raw/raw2               DATA_0001              1        2 NORMAL          CACHED         MEMBER              ONLINE

6 rows selected.

SQL> alter diskgroup DATA add disk '/dev/raw/raw6';
alter diskgroup DATA add disk '/dev/raw/raw6'
*
ERROR at line 1:
ORA-15032: not all alterations performed
ORA-15033: disk '/dev/raw/raw6' belongs to diskgroup "DATA"

SQL> alter diskgroup DATA add disk '/dev/raw/raw6' force;

Diskgroup altered.

SQL>   select PATH,NAME,DISK_NUMBER,GROUP_NUMBER,STATE,MOUNT_STATUS,HEADER_STATUS,MODE_STATUS from v$asm_disk;

PATH                   NAME            DISK_NUMBER GROUP_NUMBER STATE          MOUNT_STATUS   HEADER_STATUS          MODE_STATUS
------------------------------ -------------------- ----------- ------------ ---------------- -------------- ------------------------ --------------
/dev/raw/raw1               DATA_0000              0        2 NORMAL          CACHED         MEMBER              ONLINE
/dev/raw/raw3               DATA_0002              2        2 NORMAL          CACHED         MEMBER              ONLINE
/dev/raw/raw4               DATA1_0000              0        1 NORMAL          CACHED         MEMBER              ONLINE
/dev/raw/raw5               DATA1_0001              1        1 NORMAL          CACHED         MEMBER              ONLINE
/dev/raw/raw2               DATA_0001              1        2 NORMAL          CACHED         MEMBER              ONLINE
/dev/raw/raw6               DATA_0005              5        2 NORMAL          CACHED         MEMBER              ONLINE

6 rows selected.

SQL>     select NAME, TOTAL_MB, FREE_MB, (TOTAL_MB - FREE_MB) USED_MB, to_char((TOTAL_MB - FREE_MB) * 100 / TOTAL_MB,'99.99') || '%' USED_PRECENT from v$asm_diskgroup;

NAME               TOTAL_MB    FREE_MB    USED_MB USED_PRECENT
-------------------- ---------- ---------- ---------- --------------
DATA1               1998       1901       97   4.85%
DATA               3497       1128   2369 67.74%

实际测试中，第一和第三种方法都可行（因本测试环境未使用oracleasm，故不测试第二种）。
因第一种方法较为稳妥，故选择第一种方法在生产环境修复问题。

后续：
1、几天后在生产环境pboss2-rdb1/2 江苏库使用第一种方法修复成功。但是引出一个问题：suse系统和rhel系统在udev上有一些差异，rhel修改完 /etc/udev/rules.d/下的 rules文件，通过命令start_udev启动udev即可。但是suse则需要如下操作/etc/init.d/boot.udev restart 重启udev配置，然后模拟拔插 udevadm test /sys/block/xxx 才能使设置生效。当时没发现这个差异，只能通过重启系统生效。
2、在asmdisk加进diskgroup后，正在做rebalance过程中，使用两种方法改变asmdisk权限。一种是直接操作系统chown命令改变两个节点的asmdisk，结果发现rebalance正常进行，diskgroup不受影响。另一种是使用udev改变asmdisk属性，重启udev使之生效，结果发现diskgroup异常，直接unmount，数据库实例down，把asmdisk权限修改回来后，重新alter diskgroup xxx mount后，发现rebalance继续进行，数据库重启后正常。