
On Fri, Jul 16, 2021 at 1:59 PM Vojtech Juranek <vjuranek@redhat.com> wrote:
On Fri, Jul 16, 2021 at 11:15 AM Vojtech Juranek <vjuranek@redhat.com>
wrote:
What to do to crosscheck what is using the device and so preventing
On Friday, 16 July 2021 12:31:34 CEST Gianluca Cecchi wrote: the
"-f" to complete?
can you try
dmsetup info /dev/mapper/36090a0d800851c9d2195d5b837c9e328
and check "Open count" filed to see if there is still anything open?
Also, you can try
fuser /dev/dm-2
to see which process is using the device
[root@ov301 ~]# dmsetup info /dev/mapper/36090a0d800851c9d2195d5b837c9e328 Name: 36090a0d800851c9d2195d5b837c9e328 State: ACTIVE Read Ahead: 256 Tables present: LIVE Open count: 1
This means there's some open connection. As lsof or fuser doesn't show anything I wonder how this could happen.
Theoretically (not tested as I actually don't know how to reproduce this) and on your own risk:-), you can try
dmsetup suspend /dev/mapper/36090a0d800851c9d2195d5b837c9e328 dmsetup clear /dev/mapper/36090a0d800851c9d2195d5b837c9e328 dmsetup wipe_table /dev/mapper/36090a0d800851c9d2195d5b837c9e328
which should remove any stale connection. After that dmsetup info should show Open count 0 and multipath -f 36090a0d800851c9d2195d5b837c9e328 should work
The host doesn't see the storage any more, and anyway it's a test system where I try with oVirt, before going with oVirt itself or RHV in production. [root@ov301 ~]# dmsetup suspend /dev/mapper/36090a0d800851c9d2195d5b837c9e328 [root@ov301 ~]# dmsetup clear /dev/mapper/36090a0d800851c9d2195d5b837c9e328 [root@ov301 ~]# dmsetup wipe_table /dev/mapper/36090a0d800851c9d2195d5b837c9e328 But still [root@ov301 ~]# dmsetup info /dev/mapper/36090a0d800851c9d2195d5b837c9e328 Name: 36090a0d800851c9d2195d5b837c9e328 State: ACTIVE Read Ahead: 256 Tables present: LIVE Open count: 1 Event number: 0 Major, minor: 253, 2 Number of targets: 1 UUID: mpath-36090a0d800851c9d2195d5b837c9e328 Anyway the removal operation now goes ok: [root@ov301 ~]# multipath -f 36090a0d800851c9d2195d5b837c9e328 [root@ov301 ~]# echo $? 0 and no multipath device in my output [root@ov301 ~]# multipath -l 364817197c52f98316900666e8c2b0b2b dm-14 EQLOGIC,100E-00 size=2.0T features='1 queue_if_no_path' hwhandler='1 alua' wp=rw `-+- policy='round-robin 0' prio=0 status=active |- 16:0:0:0 sde 8:64 active undef running `- 17:0:0:0 sdf 8:80 active undef running [root@ov301 ~]# In /var/log/messages, during the sequence of commands above I see: Jul 16 14:08:20 ov301 multipathd[1580]: 36090a0d800851c9d2195d5b837c9e328: removing map by alias Jul 16 14:08:20 ov301 multipath[2229532]: dm-2 is not a multipath map Jul 16 14:09:03 ov301 multipathd[1580]: 36090a0d800851c9d2195d5b837c9e328: remove map (operator) Jul 16 14:09:03 ov301 multipathd[1580]: 36090a0d800851c9d2195d5b837c9e328: devmap not registered, can't remove Thanks for the moment... I'm going to do similar storage moving and decommissioning of the old one for 4 other storage domains (two of them iSCSI -> iSCSI, two of them iSCSI -> FC) belonging to RHV environments (4.4.6 at the moment) in the next weeks, so in case I'm going to open a case for them if I find the same strange behavior. Gianluca