hi,
i'm using three different generations of hardware for my oVirt
hypervisor hosts. they are not exactly the "same", but very
"similar".
- all were installed with oVirt Node 4.1.x installers
- all have (2-4) local SSD disks for oVirt Node OS
- all were configured with manual partitioning and SW RAID 1 with two
SSD disks for oVirt Node OS
after initializing the third generation of hosts (with 4 SSD disks) i
noticed the difference in multipath configuration for the local disks.
suddenly the two OS disks (for RAID 1) are not configured as multipath
disks anymore, the unused other two are multipath disks. in the first
two host generations the (only) two OS disks (for RAID 1) are configured
as multipath disks.
after looking at this for the first time and briefly looking into
multipath documentation i think that local disks shouldn't be included
in multipath configuration at all. i tried to remove the local disks
from multipathing (delete from wwids file, explicit blacklisting), to no
avail.
i'm pasting two listings from the 4 SSD disk situation:
# lsscsi --scsi_id -g
[0:0:0:0] disk ATA SAMSUNG MZ7LM480 204Q /dev/sda - /dev/sg0
[0:0:1:0] disk ATA SAMSUNG MZ7LM480 204Q /dev/sdb - /dev/sg1
[0:0:2:0] disk ATA SAMSUNG MZ7LM480 204Q /dev/sdc
SAMSUNG_MZ7LM480HMHQ-00005_S2UJNX0J102216 /dev/sg2
[0:0:3:0] disk ATA SAMSUNG MZ7LM480 204Q /dev/sdd
SAMSUNG_MZ7LM480HMHQ-00005_S2UJNX0J102214 /dev/sg3
# ls -l /dev/disk/by-id/*SAMSUNG*
lrwxrwxrwx. 1 root root 9 9. Okt 12:07
/dev/disk/by-id/ata-SAMSUNG_MZ7LM480HMHQ-00005_S2UJNX0J102212 -> ../../sdb
lrwxrwxrwx. 1 root root 10 9. Okt 12:07
/dev/disk/by-id/ata-SAMSUNG_MZ7LM480HMHQ-00005_S2UJNX0J102212-part1 ->
../../sdb1
lrwxrwxrwx. 1 root root 10 9. Okt 12:07
/dev/disk/by-id/ata-SAMSUNG_MZ7LM480HMHQ-00005_S2UJNX0J102212-part2 ->
../../sdb2
lrwxrwxrwx. 1 root root 9 9. Okt 12:07
/dev/disk/by-id/ata-SAMSUNG_MZ7LM480HMHQ-00005_S2UJNX0J102214 -> ../../sdd
lrwxrwxrwx. 1 root root 9 9. Okt 12:07
/dev/disk/by-id/ata-SAMSUNG_MZ7LM480HMHQ-00005_S2UJNX0J102216 -> ../../sdc
lrwxrwxrwx. 1 root root 9 9. Okt 12:07
/dev/disk/by-id/ata-SAMSUNG_MZ7LM480HMHQ-00005_S2UJNX0J102222 -> ../../sda
lrwxrwxrwx. 1 root root 10 9. Okt 12:07
/dev/disk/by-id/ata-SAMSUNG_MZ7LM480HMHQ-00005_S2UJNX0J102222-part1 ->
../../sda1
lrwxrwxrwx. 1 root root 10 9. Okt 12:07
/dev/disk/by-id/ata-SAMSUNG_MZ7LM480HMHQ-00005_S2UJNX0J102222-part2 ->
../../sda2
lrwxrwxrwx. 1 root root 10 9. Okt 12:07
/dev/disk/by-id/dm-name-SAMSUNG_MZ7LM480HMHQ-00005_S2UJNX0J102214 ->
../../dm-6
lrwxrwxrwx. 1 root root 10 9. Okt 12:07
/dev/disk/by-id/dm-name-SAMSUNG_MZ7LM480HMHQ-00005_S2UJNX0J102216 ->
../../dm-5
lrwxrwxrwx. 1 root root 10 9. Okt 12:07
/dev/disk/by-id/dm-uuid-mpath-SAMSUNG_MZ7LM480HMHQ-00005_S2UJNX0J102214
-> ../../dm-6
lrwxrwxrwx. 1 root root 10 9. Okt 12:07
/dev/disk/by-id/dm-uuid-mpath-SAMSUNG_MZ7LM480HMHQ-00005_S2UJNX0J102216
-> ../../dm-5
can someone explain this behaviour? what is the _intended_ configuration?
thx
matthias