First excuse me for a looong message, but I've tryed to give as much relevant details as possible.
Please help me with this weird setup if it is possible and fesable:
I have this raid1 device, composed of two fibre channel devices mounted in RAID1, it works absolutely flawlessly.
The resulted device is used for a lot of important data logging and the ideea is to hotattach a 3-rd device ot the same size, wait for syncronisation and after all of them are syncronised, stop the data logging process, wait for a while, issue a sync command and hot detach the 3-rd device restart de data logging and walk away with valid filesytem backup of the main arry to be used as separate data analysys source. I know that solution is somewhat cumberome but trust me this is needed as is.
Now if you read untill here I managed to hot-attach, the attaching was mentioned in the syslogfile, the data logging process continued undisturbed, even the cat /proc/mdstat showed the new device added BUT it only showed the same two [2/2] [UU] and it didn't touch the 3-rd disk at all, also hotremoving was sucessful.
Here are some relevant data of the test setup that may be usefull: [root@test]# cat /etc/raidtab raiddev /dev/md0 raid-level 1 nr-raid-disks 2 nr-spare-disks 0 chunk-size 4 persistent-superblock 1 device /dev/sda2 raid-disk 0 device /dev/sdb2 raid-disk 1
/proc/mdstat BEFORE adding the 3-rd device:
[root@test]# cat /proc/mdstat
Personalities : [raid1]
read_ahead 1024 sectors
md0 : active raid1 scsi/host3/bus0/target0/lun0/part2[1] scsi/host2/bus0/target0/lun0/part2[0]
710938560 blocks [2/2] [UU]
unused devices: <none>
Then I add the 3-rd device: [root@test]# raidhotadd /dev/md0 /dev/sdb3
/proc/mdstat AFTER adding 3-rd device
[root@nfs10 root]# cat /proc/mdstat
Personalities : [raid1]
read_ahead 1024 sectors
md0 : active raid1 scsi/host3/bus0/target0/lun0/part3[2] scsi/host3/bus0/target0/lun0/part2[1] scsi/host2/bus0/target0/lun0/part2[0]
710938560 blocks [2/2] [UU]
unused devices: <none>
Piece of the syslog showing the add results:
.....
Jan 7 12:09:01 nfs10 kernel: md: updating md0 RAID superblock on device
Jan 7 12:09:01 nfs10 kernel: md: scsi/host3/bus0/target0/lun0/part3 [events: 00000012]<6>(write) scsi/host3/bus0/target0/lun0/part3's sb offset: 725598144
Jan 7 12:09:01 nfs10 kernel: md: scsi/host3/bus0/target0/lun0/part2 [events: 00000012]<6>(write) scsi/host3/bus0/target0/lun0/part2's sb offset: 710938560
Jan 7 12:09:01 nfs10 kernel: md: scsi/host2/bus0/target0/lun0/part2 [events: 00000012]<6>(write) scsi/host2/bus0/target0/lun0/part2's sb offset: 710938560
......
The problem is that no sync is done, as a matter of fact the 3rd disk is not even scrached visibly ;(, did I miss someting obvious or what I want is impossible ???
Thank you for reading such a long mail and for any help that will lead me solving this,
Mircea Ciocan
- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
