On Thu, Jul 13, 2017 at 6:23 PM, Gianluca Cecchi <gianluca.cecchi@gmail.com> wrote:
Hello,
I have cleanly removed an iSCSI domain from oVirt. There is another one (connecting to another storage array) that is the master domain.  
But I see that oVirt hosts still maintain the iscsi session to the LUN.
So I want to clean from os point of view before removing the LUN itself from storage.

At the moment I still see the multipath lun on both hosts

[root@ov301 network-scripts]# multipath -l
. . .
364817197b5dfd0e5538d959702249b1c dm-2 EQLOGIC ,100E-00         
size=4.0T features='0' hwhandler='0' wp=rw
`-+- policy='round-robin 0' prio=0 status=active
  |- 9:0:0:0  sde 8:64  active undef  running
  `- 10:0:0:0 sdf 8:80  active undef  running

and 
[root@ov301 network-scripts]# iscsiadm -m session
tcp: [1] 10.10.100.9:3260,1 iqn.2001-05.com.equallogic:4-771816-e5d0dfb59-1c9b240297958d53-ovsd3910 (non-flash)
tcp: [2] 10.10.100.9:3260,1 iqn.2001-05.com.equallogic:4-771816-e5d0dfb59-1c9b240297958d53-ovsd3910 (non-flash)
. . .

Do I have to clean the multipath paths and multipath device and then iSCSI logout, or is it sufficient to iSCSI logout and the multipath device and its path will be cleanly removed from OS point of view?

I would like not to have multipath device in stale condition.

Thanks
Gianluca


I have not understood why, if I destroy a storage domain, still oVirt maintains its LVM structures....

Anyway, these were the step done at host side before removal of the LUN at storage array level

Pick up the VG of which the lun is still a PV for..

vgchange -an 5ed04196-87f1-480e-9fee-9dd450a3b53b
--> actually all lvs were already inactive

vgremove 5ed04196-87f1-480e-9fee-9dd450a3b53b
Do you really want to remove volume group "5ed04196-87f1-480e-9fee-9dd450a3b53b" containing 22 logical volumes? [y/n]: y
  Logical volume "metadata" successfully removed
  Logical volume "outbox" successfully removed
  Logical volume "xleases" successfully removed
  Logical volume "leases" successfully removed
  Logical volume "ids" successfully removed
  Logical volume "inbox" successfully removed
  Logical volume "master" successfully removed
  Logical volume "bc141d0d-b648-409b-a862-9b6d950517a5" successfully removed
  Logical volume "31255d83-ca67-4f47-a001-c734c498d176" successfully removed
  Logical volume "607dbf59-7d4d-4fc3-ae5f-e8824bf82648" successfully removed
  Logical volume "dfbf5787-36a4-4685-bf3a-43a55e9cd4a6" successfully removed
  Logical volume "400ea884-3876-4a21-9ec6-b0b8ac706cee" successfully removed
  Logical volume "1919f6e6-86cd-4a13-9a21-ce52b9f62e35" successfully removed
  Logical volume "a3ea679b-95c0-475d-80c5-8dc4d86bd87f" successfully removed
  Logical volume "32f433c8-a991-4cfc-9a0b-7f44422815b7" successfully removed
  Logical volume "7f867f59-c977-47cf-b280-a2a0fef8b95b" successfully removed
  Logical volume "6e2005f2-3ff5-42fa-867e-e7812c6726e4" successfully removed
  Logical volume "42344cf4-8f9c-464d-ab0f-d62beb15d359" successfully removed
  Logical volume "293e169e-53ed-4d60-b22a-65835f5b0d29" successfully removed
  Logical volume "e86752c4-de73-4733-b561-2afb31bcc2d3" successfully removed
  Logical volume "79350ec5-eea5-458b-a3ee-ba394d2cda27" successfully removed
  Logical volume "77824fce-4f95-49e3-b732-f791151dd15c" successfully removed
  Volume group "5ed04196-87f1-480e-9fee-9dd450a3b53b" successfully removed

pvremove /dev/mapper/364817197b5dfd0e5538d959702249b1c

multipath -f 364817197b5dfd0e5538d959702249b1c

iscsiadm -m session -r 1 -u
Logging out of session [sid: 1, target: iqn.2001-05.com.equallogic:4-771816-e5d0dfb59-1c9b240297958d53-ovsd3910, portal: 10.10.100.9,3260]
Logout of [sid: 1, target: iqn.2001-05.com.equallogic:4-771816-e5d0dfb59-1c9b240297958d53-ovsd3910, portal: 10.10.100.9,3260] successful.

iscsiadm -m session -r 2 -u
Logging out of session [sid: 2, target: iqn.2001-05.com.equallogic:4-771816-e5d0dfb59-1c9b240297958d53-ovsd3910, portal: 10.10.100.9,3260]
Logout of [sid: 2, target: iqn.2001-05.com.equallogic:4-771816-e5d0dfb59-1c9b240297958d53-ovsd3910, portal: 10.10.100.9,3260] successful.

done.

NOTE: on one node I missed the LVM clean before logging out of the iSCSI session
this resulted in impossibility to have a clean status because the multipath device resulted as without paths but still used (by LVM)
and the command
multipath -f
failed.
Also vgs and lvs commands threw out many errors and many errors in messages too

These were the commands to clean the situation also on that node.

dmsetup remove 5ed04196-87f1-480e-9fee-9dd450a3b53b/master
dmsetup remove 5ed04196-87f1-480e-9fee-9dd450a3b53b/inbox
dmsetup remove 5ed04196-87f1-480e-9fee-9dd450a3b53b/xleases
dmsetup remove 5ed04196-87f1-480e-9fee-9dd450a3b53b/leases
dmsetup remove 5ed04196-87f1-480e-9fee-9dd450a3b53b/outbox
dmsetup remove 5ed04196-87f1-480e-9fee-9dd450a3b53b/ids
dmsetup remove 5ed04196-87f1-480e-9fee-9dd450a3b53b/metadata

multipath -f 364817197b5dfd0e5538d959702249b1c

Gianluca