VDI_IO_ERROR Continuous Replication on clean install.

Tristis Oris

@olivierlambert that a old problem) but yes, usually about latest. Just repeated all tests on 3c7d3.

CR stop working right after clean 8.2.1 installation. at same day.
replaced FC to iscsi (only bcz i need iscsi here ), created new LUN > same story.
8.2.0 clean install, no updated - CR works.
don't tried usual backups to this SR, don't need them here.
VM migration works at any setup.

problem only with one storage Dell EMC PowerVault ME4012. all other huawei, iscsi - works fine. But not sure if i have another clean 8.2.1 pools. Maybe only some nodes.

logs now. I'm doing 2 CR backups.

Xen 8.2.1, clean host, no any VM. iscsi 60Tb lun. Xen show only 50Tb

Jan 16 15:15:30 test SMGC: [10010] SR f3fd ('LUN') (2 VDIs in 2 VHD trees):
Jan 16 15:15:30 test SMGC: [10010]         a459d14f[VHD](50.000G//50.105G|ao)
Jan 16 15:15:30 test SMGC: [10010]         1789f7a7[VHD](50.000G//50.105G|ao)

Jan 16 15:15:47 test SMGC: [10338] SR f3fd ('LUN') (1 VDIs in 1 VHD trees):
Jan 16 15:15:47 test SMGC: [10338]         a459d14f[VHD](50.000G//50.105G|ao)
Jan 16 15:15:47 test SMGC: [10338]

here it 60Tb.
9623bb15-87f4-4396-8165-b98c480cb25d-изображение.png

2 vms, 2 error - SR_NOT_SUPPORTED

Jan 16 15:10:43 test SM: [6596] result: {'params_nbd': 'nbd:unix:/run/blktap-control/nbd/f3fd46f7-5ce4-e5e0-53e9-059ce4775a7b/1789f7a7-05a0-411c-aa80-dcc659f8b45f', 'o_direct_reason': 'SR_NOT_SUPPORTED', 'params': '/dev/sm/backend/f3fd46f7-5ce4-e5e0-53e9-059ce4775a7b/1789f7a7-05a0-411c-aa80-dcc659f8b45f', 'o_direct': True, 'xenstore_data': {'scsi/0x12/0x80': 'AIAAEjE3ODlmN2E3LTA1YTAtNDEgIA==', 'scsi/0x12/0x83': 'AIMAMQIBAC1YRU5TUkMgIDE3ODlmN2E3LTA1YTAtNDExYy1hYTgwLWRjYzY1OWY4YjQ1ZiA=', 'vdi-uuid': '1789f7a7-05a0-411c-aa80-dcc659f8b45f', 'mem-pool': 'f3fd46f7-5ce4-e5e0-53e9-059ce4775a7b'}}
Jan 16 15:10:49 test SM: [6834] result: {'params_nbd': 'nbd:unix:/run/blktap-control/nbd/f3fd46f7-5ce4-e5e0-53e9-059ce4775a7b/a459d14f-ae92-4a77-8574-30442126624b', 'o_direct_reason': 'SR_NOT_SUPPORTED', 'params': '/dev/sm/backend/f3fd46f7-5ce4-e5e0-53e9-059ce4775a7b/a459d14f-ae92-4a77-8574-30442126624b', 'o_direct': True, 'xenstore_data': {'scsi/0x12/0x80': 'AIAAEmE0NTlkMTRmLWFlOTItNGEgIA==', 'scsi/0x12/0x83': 'AIMAMQIBAC1YRU5TUkMgIGE0NTlkMTRmLWFlOTItNGE3Ny04NTc0LTMwNDQyMTI2NjI0YiA=', 'vdi-uuid': 'a459d14f-ae92-4a77-8574-30442126624b', 'mem-pool': 'f3fd46f7-5ce4-e5e0-53e9-059ce4775a7b'}}

and some small like

Jan 16 15:14:30 test SM: [9387] Failed to lock /var/lock/sm/.nil/lvm on first attempt, blocked by PID 9357
	Line  184: Jan 16 15:10:29 test SM: [6376] Failed to lock /var/lock/sm/.nil/lvm on first attempt, blocked by PID 6348
	Line  571: Jan 16 15:10:59 test SM: [7141] Failed to lock /var/lock/sm/.nil/lvm on first attempt, blocked by PID 7115
	Line  717: Jan 16 15:11:30 test SM: [7457] Failed to lock /var/lock/sm/.nil/lvm on first attempt, blocked by PID 7428
	Line 1927: Jan 16 15:15:43 test SM: [10146] unlink of attach_info failed

nothing more with error status at log.

because of weird size, tried 8.2.1 with iscsi 20Tb LUN.
same result SR_NOT_SUPPORTED.
now 8.2.0 clean install, no any updates.
it works.

here both hosts connected to same SR.
56fe4456-4d1b-4fc7-85b5-6ecfd6090421-изображение.png

8.2.0 full updates > 8.2.1 release/yangtze/master/58
CR still working.

4.1. unmount LUN, mount again.
working.

olivierlambert

I have no idea, sorry. So to recap:

doesn't work on a 8.2.1 fresh install with updates
works on older 8.2.0
work on 8.2.0 updated to 8.2.1

It doesn't sound like an XO bug in your case.

Tristis Oris

@olivierlambert yes. so what to do next?)

olivierlambert

Trying to figure the setup so we can try to reproduce, and also switching various things until there's a clear pattern.

Eg: can you try with an NFS share to see if you have the same issue? If it's iSCSI related, that would help us to investigate.

Tristis Oris

i can't, this is only SAN storage.
any point to test on 8.3 alpha?

olivierlambert

You can, it's still another test that might help us to pinpoint something

yomono

@olivierlambert I would like to add that after this recap I realized... I also had to reinstall XCP so in my case it's also a fresh 8.2.1 install! At least. knowing that, I can do a 8.2.0 + upgrade installation.. (that's what I used to have). I can also try 8.3 alpha, it's not like I have anything to lose at this point (that server is only to contain XO, there is nothing else there)
Anyways.. the fresh 8.2.1 install is definitely the common point here

olivierlambert

Also with iSCSI storage, right?

yomono

@olivierlambert not really. This time is just local ext storage, SATA drives.

olivierlambert

In LVM or thin? It might be 2 different problems, so I'm trying to sort this out.

yomono

@olivierlambert both! I have both mixed in my servers and I tried in both when I did the tests

Tristis Oris

just remember i have one server with fresh 8.2.1 and nfs backups to TrueNAS. it working.
will do other tests tomorrow.

Tristis Oris

@olivierlambert
sr_not_supported that not a error and not a reason. That because of default multipath Dell config for 3xxx series. Persist at 8.2.0 where CR working, so that just a warning.
As we have no any problems before, we never investigate to this setting. My bad again yay.

Replaced it to official for 4xxx and this warning gone. I see at 8.3 it already more universal for any generation.

        device {
                vendor "DellEMC"
                product "ME4"
                path_grouping_policy "group_by_prio"
                path_checker "tur"
                hardware_handler "1 alua"
                prio "alua"
                failback immediate
                path_selector "service-time 0"
        }

since it no default config for huawei, so we always used the official one.

        device {
                vendor                  "HUAWEI"
                product                 "XSG1"
                path_grouping_policy multibus
                path_checker            tur
                prio                    const
                path_selector           "round-robin 0"
                failback                immediate
                fast_io_fail_tmo        5
                dev_loss_tmo            30
        }

8.2.1:
CR not working:
both huawei, dell iscsi - multipath enabled
both huawei, dell iscsi - multipath disabled
working:
nfs vm disk
local thin\ext
local thick\lvm
8.3
working:
both huawei, dell iscsi - multipath enabled
local thick\lvm

and now interesting. After i solved this false warning, detach extra hosts from pool, detach all additional links (trunk, backup) to decrease comunications and log itself - it's no any SMlog generated during backup task.

MP enabled - with 2nd link for backup https://pastebin.com/URcnDckR
MP enabled - only Mng link, no SMlog generated https://pastebin.com/RHw40uzg

olivierlambert

I have the impression it's good news, but I'm not 100% sure to get it, can you rephrase a bit your conclusion?

Tristis Oris

if i have no smlog - xen\dom0 not related with backup task. right?
smlog that usualy i got during this 5min have no any errors anyway, only some locking operations.
And it always takes 5min, some hardcoded timings?

don't forget that problem also happens with FC connection, so it may concern any block based storage types.

olivierlambert

I don't understand your sentence, can you take time to re-read it or rephrase it, because I doesn't make sense to me, sorry

What do you mean by "if i have no smlog - xen\dom0 not related with backup task. right?"?

Tristis Oris

i mean it could be XO issue, since it not communicate with xen. Otherwise it should write some logs.

olivierlambert

I don't see the logical connection with XO, since it works on some SR and not on others. XO has no idea (or doesn't care) about the underlying storage.

Tristis Oris

well, i'm just made some tests and got some result. Have no idea how it should work)

Tristis Oris

i don't understand what happens.
Reinstalled xen to 8.2.0, CR was succeed for few times, but now i got this error again.

Tried few tests - 2-3 fails in row then it succeed again.
Only way to never use this pool for CR.