<div dir="auto"><div><br><div class="gmail_extra"><br><div class="gmail_quote">On Oct 10, 2017 12:23 PM, "Matthias Leopold" <<a href="mailto:matthias.leopold@meduniwien.ac.at">matthias.leopold@meduniwien.ac.at</a>> wrote:<br type="attribution"><blockquote class="quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">hi,<br>
<br>
i'm using three different generations of hardware for my oVirt hypervisor hosts. they are not exactly the "same", but very "similar".<br>
<br>
- all were installed with oVirt Node 4.1.x installers<br>
- all have (2-4) local SSD disks for oVirt Node OS<br>
- all were configured with manual partitioning and SW RAID 1 with two SSD disks for oVirt Node OS<br>
<br>
after initializing the third generation of hosts (with 4 SSD disks) i noticed the difference in multipath configuration for the local disks. </blockquote></div></div></div><div dir="auto"><br></div><div dir="auto">I may be wrong but it rarely matters on local disks. Unless they have some kind of active-active (multi-channel?) controllers. </div><div dir="auto">Y. </div><div dir="auto"><br></div><div dir="auto"><div class="gmail_extra"><div class="gmail_quote"><blockquote class="quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">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.<br>
<br>
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.<br>
<br>
i'm pasting two listings from the 4 SSD disk situation:<br>
<br>
# lsscsi --scsi_id -g<br>
[0:0:0:0] disk ATA SAMSUNG MZ7LM480 204Q /dev/sda - /dev/sg0<br>
[0:0:1:0] disk ATA SAMSUNG MZ7LM480 204Q /dev/sdb - /dev/sg1<br>
[0:0:2:0] disk ATA SAMSUNG MZ7LM480 204Q /dev/sdc SAMSUNG_MZ7LM480HMHQ-00005_S2U<wbr>JNX0J102216 /dev/sg2<br>
[0:0:3:0] disk ATA SAMSUNG MZ7LM480 204Q /dev/sdd SAMSUNG_MZ7LM480HMHQ-00005_S2U<wbr>JNX0J102214 /dev/sg3<br>
<br>
# ls -l /dev/disk/by-id/*SAMSUNG*<br>
lrwxrwxrwx. 1 root root 9 9. Okt 12:07 /dev/disk/by-id/ata-SAMSUNG_MZ<wbr>7LM480HMHQ-00005_S2UJNX0J10221<wbr>2 -> ../../sdb<br>
lrwxrwxrwx. 1 root root 10 9. Okt 12:07 /dev/disk/by-id/ata-SAMSUNG_MZ<wbr>7LM480HMHQ-00005_S2UJNX0J10221<wbr>2-part1 -> ../../sdb1<br>
lrwxrwxrwx. 1 root root 10 9. Okt 12:07 /dev/disk/by-id/ata-SAMSUNG_MZ<wbr>7LM480HMHQ-00005_S2UJNX0J10221<wbr>2-part2 -> ../../sdb2<br>
lrwxrwxrwx. 1 root root 9 9. Okt 12:07 /dev/disk/by-id/ata-SAMSUNG_MZ<wbr>7LM480HMHQ-00005_S2UJNX0J10221<wbr>4 -> ../../sdd<br>
lrwxrwxrwx. 1 root root 9 9. Okt 12:07 /dev/disk/by-id/ata-SAMSUNG_MZ<wbr>7LM480HMHQ-00005_S2UJNX0J10221<wbr>6 -> ../../sdc<br>
lrwxrwxrwx. 1 root root 9 9. Okt 12:07 /dev/disk/by-id/ata-SAMSUNG_MZ<wbr>7LM480HMHQ-00005_S2UJNX0J10222<wbr>2 -> ../../sda<br>
lrwxrwxrwx. 1 root root 10 9. Okt 12:07 /dev/disk/by-id/ata-SAMSUNG_MZ<wbr>7LM480HMHQ-00005_S2UJNX0J10222<wbr>2-part1 -> ../../sda1<br>
lrwxrwxrwx. 1 root root 10 9. Okt 12:07 /dev/disk/by-id/ata-SAMSUNG_MZ<wbr>7LM480HMHQ-00005_S2UJNX0J10222<wbr>2-part2 -> ../../sda2<br>
lrwxrwxrwx. 1 root root 10 9. Okt 12:07 /dev/disk/by-id/dm-name-SAMSUN<wbr>G_MZ7LM480HMHQ-00005_S2UJNX0J1<wbr>02214 -> ../../dm-6<br>
lrwxrwxrwx. 1 root root 10 9. Okt 12:07 /dev/disk/by-id/dm-name-SAMSUN<wbr>G_MZ7LM480HMHQ-00005_S2UJNX0J1<wbr>02216 -> ../../dm-5<br>
lrwxrwxrwx. 1 root root 10 9. Okt 12:07 /dev/disk/by-id/dm-uuid-mpath-<wbr>SAMSUNG_MZ7LM480HMHQ-00005_S2U<wbr>JNX0J102214 -> ../../dm-6<br>
lrwxrwxrwx. 1 root root 10 9. Okt 12:07 /dev/disk/by-id/dm-uuid-mpath-<wbr>SAMSUNG_MZ7LM480HMHQ-00005_S2U<wbr>JNX0J102216 -> ../../dm-5<br>
<br>
can someone explain this behaviour? what is the _intended_ configuration?<br>
<br>
thx<br>
matthias<br>
<br>
<br>
<br>
______________________________<wbr>_________________<br>
Users mailing list<br>
<a href="mailto:Users@ovirt.org" target="_blank">Users@ovirt.org</a><br>
<a href="http://lists.ovirt.org/mailman/listinfo/users" rel="noreferrer" target="_blank">http://lists.ovirt.org/mailman<wbr>/listinfo/users</a><br>
</blockquote></div><br></div></div></div>