测试一体机ASM Disk online操作

环境：3台虚拟机 RHEL 7.3 + Oracle RAC 11.2.0.4

问题现象：RAC运行正常，ASM磁盘组Normal冗余，节点主机重启，offline状态的asm disk短时间内可以直接online。

在《测试一体机ASM failgroup的相关问题处理》之前的文章，描述了重新添加磁盘的场景，其实如果故障发现及时（默认3.6h内），是可以直接online对应磁盘的，这时候现象类似如下：

SQL> select group_number, disk_number, name, path, failgroup, mode_status, voting_file  from v$asm_disk order by 1, 2;
GROUP_NUMBER DISK_NUMBER NAME                           PATH                                FAILGROUP                      MODE_STATUS    VO
------------ ----------- ------------------------------ ----------------------------------- ------------------------------ -------------- --
           0           0                                /dev/CELL01-data2                                                  ONLINE         N
           0           1                                /dev/CELL01-data1                                                  ONLINE         N
           0           2                                /dev/CELL01-crs1                                                   ONLINE         Y
           1           0 CRS_0000                                                           CRS_0000                       OFFLINE        N
           1           1 CRS_0001                       /dev/CELL02-crs2                    CRS_0001                       ONLINE         Y
           1           2 CRS_0002                       /dev/CELL03-crs3                    CRS_0002                       ONLINE         Y
           2           0 DATA_0000                      /dev/CELL03-data1                   CELL03                         ONLINE         N
           2           1 DATA_0001                      /dev/CELL03-data2                   CELL03                         ONLINE         N
           2           2 DATA_0002                      /dev/CELL02-data1                   CELL02                         ONLINE         N
           2           3 DATA_0003                      /dev/CELL02-data2                   CELL02                         ONLINE         N
           2           4 DATA_0004                                                          CELL01                         OFFLINE        N
           2           5 DATA_0005                                                          CELL01                         OFFLINE        N

12 rows selected.

这种情况就可以直接online对应磁盘:

SQL> alter diskgroup CRS online disk CRS_0000;

Diskgroup altered.

SQL> alter diskgroup DATA online disk DATA_0004,DATA_0005;
alter diskgroup DATA online disk DATA_0004,DATA_0005
*
ERROR at line 1:
ORA-15032: not all alterations performed
ORA-15282: ASM disk "DATA_0005" is not visible cluster-wide
ORA-15282: ASM disk "DATA_0004" is not visible cluster-wide

直接online对应磁盘如果遇到上面这个报错，因为有其他节点没有看到要online的磁盘，检查其他节点：

[root@db02 ~]# ls -l /dev/CELL*
lrwxrwxrwx 1 root root 3 Dec  2 21:16 /dev/CELL01-crs1 -> sdc
lrwxrwxrwx 1 root root 3 Dec  2 21:16 /dev/CELL02-crs2 -> sdi
lrwxrwxrwx 1 root root 3 Dec  2 21:16 /dev/CELL02-data1 -> sdj
lrwxrwxrwx 1 root root 3 Dec  2 21:16 /dev/CELL02-data2 -> sdk
lrwxrwxrwx 1 root root 3 Dec  2 21:16 /dev/CELL03-crs3 -> sdd
lrwxrwxrwx 1 root root 3 Dec  2 21:16 /dev/CELL03-data1 -> sdf
lrwxrwxrwx 1 root root 3 Dec  2 21:16 /dev/CELL03-data2 -> sdh

此时先要确认lsscsi底层正常（如果不正常先解决iscsi层的问题，我这里是正常的）：

[root@db02 ~]# lsscsi
[1:0:0:0]    cd/dvd  VBOX     CD-ROM           1.0   /dev/sr0
[2:0:0:0]    disk    ATA      VBOX HARDDISK    1.0   /dev/sda
[3:0:0:0]    disk    ATA      VBOX HARDDISK    1.0   /dev/sdb
[4:0:0:0]    disk    LIO-ORG  disk1            4.0   /dev/sdc
[4:0:0:1]    disk    LIO-ORG  disk2            4.0   /dev/sde
[4:0:0:2]    disk    LIO-ORG  disk3            4.0   /dev/sdg
[5:0:0:0]    disk    LIO-ORG  disk1            4.0   /dev/sdd
[5:0:0:1]    disk    LIO-ORG  disk2            4.0   /dev/sdf
[5:0:0:2]    disk    LIO-ORG  disk3            4.0   /dev/sdh
[6:0:0:0]    disk    LIO-ORG  disk1            4.0   /dev/sdi
[6:0:0:1]    disk    LIO-ORG  disk2            4.0   /dev/sdj
[6:0:0:2]    disk    LIO-ORG  disk3            4.0   /dev/sdk

重新刷新udev规则，确认所有磁盘识别正确：

[root@db02 ~]# udevadm control --reload
[root@db02 ~]# udevadm trigger
[root@db02 ~]# ls -l /dev/CELL*
lrwxrwxrwx 1 root root 3 Dec  2 21:18 /dev/CELL01-crs1 -> sdc
lrwxrwxrwx 1 root root 3 Dec  2 21:18 /dev/CELL01-data1 -> sde
lrwxrwxrwx 1 root root 3 Dec  2 21:18 /dev/CELL01-data2 -> sdg
lrwxrwxrwx 1 root root 3 Dec  2 21:18 /dev/CELL02-crs2 -> sdi
lrwxrwxrwx 1 root root 3 Dec  2 21:18 /dev/CELL02-data1 -> sdj
lrwxrwxrwx 1 root root 3 Dec  2 21:18 /dev/CELL02-data2 -> sdk
lrwxrwxrwx 1 root root 3 Dec  2 21:18 /dev/CELL03-crs3 -> sdd
lrwxrwxrwx 1 root root 3 Dec  2 21:18 /dev/CELL03-data1 -> sdf
lrwxrwxrwx 1 root root 3 Dec  2 21:18 /dev/CELL03-data2 -> sdh

然后再次进行online磁盘成功：

SQL> alter diskgroup DATA online disk DATA_0004,DATA_0005; 

Diskgroup altered.

这种可以直接online disk的情况就免去了ASM磁盘组rebalance的大量时间，所以这类问题发现后最好要及时联系工程师进行处理。