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Hi Eugen,

I have a few questions before we close this thread.

- Is it normal that ceph locks images during power failure or disaster?
- Shouldn't ceph should release locks automatically when VMs shutdown?
- Is this a bug or natural behavior of ceph? I am worried what if i have
100s of VMs and remove lock of all of them



On Fri, Feb 17, 2023 at 10:28 AM Satish Patel <satish.txt at gmail.com> wrote:

> Hi Eugen,
>
> You saved my life!!!!!! all my vms up without any filesystem error :)
>
> This is the correct command to remove the lock.
>
> $ rbd lock rm -p vms ec6044e6-2231-4906-9e30-1e2e72573e64_disk "auto
> 139643345791728" client.1211875
>
>
>
> On Fri, Feb 17, 2023 at 10:06 AM Satish Patel <satish.txt at gmail.com>
> wrote:
>
>> Hi Eugen,
>>
>> I am playing with less important machine and i did following
>>
>> I shutdown VM but still down following lock
>>
>> root at ceph1:~# rbd lock list --image
>> ec6044e6-2231-4906-9e30-1e2e72573e64_disk -p vms
>> There is 1 exclusive lock on this image.
>> Locker          ID                    Address
>> client.1211875  auto 139643345791728  192.168.3.12:0/2259335316
>>
>> root at ceph1:~# ceph osd blacklist add 192.168.3.12:0/2259335316
>> blocklisting 192.168.3.12:0/2259335316 until
>> 2023-02-17T16:00:59.399775+0000 (3600 sec)
>>
>> Still I can see it in the following lock list. Am I missing something?
>>
>> root at ceph1:~# rbd lock list --image
>> ec6044e6-2231-4906-9e30-1e2e72573e64_disk -p vms
>> There is 1 exclusive lock on this image.
>> Locker          ID                    Address
>> client.1211875  auto 139643345791728  192.168.3.12:0/2259335316
>>
>>
>>
>> On Fri, Feb 17, 2023 at 2:39 AM Eugen Block <eblock at nde.ag> wrote:
>>
>>> The lock is aquired automatically, you don't need to create one. I'm
>>> curious why you have that many blacklist entries, maybe that is indeed
>>> the issue here (locks are not removed). I would shutdown the corrupted
>>> VM and see if the compute node still has a lock on that image, because
>>> after shutdown it should remove the lock (automatically). If there's
>>> still a watcher or lock on that image after shutdown (rbd status
>>> vms/55dbf40b-0a6a-4bab-b3a5-b4bb74e963af_disk) you can try to
>>> blacklist the client with:
>>>
>>> # ceph osd blacklist add client.<ID>
>>>
>>> Then check the status again, if no watchers are present, boot the VM.
>>>
>>>
>>> Zitat von Satish Patel <satish.txt at gmail.com>:
>>>
>>> > Hi Eugen,
>>> >
>>> > This is what I did, let me know if I missed anything.
>>> >
>>> > root at ceph1:~# ceph osd blacklist ls
>>> > 192.168.3.12:0/0 2023-02-17T04:48:54.381763+0000
>>> > 192.168.3.22:0/753370860 2023-02-17T04:47:08.185434+0000
>>> > 192.168.3.22:0/2833179066 2023-02-17T04:47:08.185434+0000
>>> > 192.168.3.22:0/1812968936 2023-02-17T04:47:08.185434+0000
>>> > 192.168.3.22:6824/2057987683 2023-02-17T04:47:08.185434+0000
>>> > 192.168.3.21:0/2756666482 2023-02-17T05:16:23.939511+0000
>>> > 192.168.3.21:0/1646520197 2023-02-17T05:16:23.939511+0000
>>> > 192.168.3.22:6825/2057987683 2023-02-17T04:47:08.185434+0000
>>> > 192.168.3.21:0/526748613 2023-02-17T05:16:23.939511+0000
>>> > 192.168.3.21:6815/2454821797 2023-02-17T05:16:23.939511+0000
>>> > 192.168.3.22:0/288537807 2023-02-17T04:47:08.185434+0000
>>> > 192.168.3.21:0/4161448504 2023-02-17T05:16:23.939511+0000
>>> > 192.168.3.21:6824/2454821797 2023-02-17T05:16:23.939511+0000
>>> > listed 13 entries
>>> >
>>> > root at ceph1:~# rbd lock list --image
>>> > 55dbf40b-0a6a-4bab-b3a5-b4bb74e963af_disk -p vms
>>> > There is 1 exclusive lock on this image.
>>> > Locker         ID                    Address
>>> > client.268212  auto 139971105131968  192.168.3.12:0/1649312807
>>> >
>>> > root at ceph1:~# ceph osd blacklist rm 192.168.3.12:0/1649312807
>>> > 192.168.3.12:0/1649312807 isn't blocklisted
>>> >
>>> > How do I create a lock?
>>> >
>>> >
>>> > On Thu, Feb 16, 2023 at 10:45 AM Eugen Block <eblock at nde.ag> wrote:
>>> >
>>> >> In addition to Sean's response, this has been asked multiple times,
>>> >> e.g. [1]. You could check if your hypervisors gave up the lock on the
>>> >> RBDs or if they are still locked (rbd status <pool>/<image>), in that
>>> >> case you might need to blacklist the clients and see if that resolves
>>> >> anything. Do you have regular snapshots (or backups) to be able to
>>> >> rollback in case of a curruption?
>>> >>
>>> >> [1] https://www.spinics.net/lists/ceph-users/msg45937.html
>>> >>
>>> >>
>>> >> Zitat von Sean Mooney <smooney at redhat.com>:
>>> >>
>>> >> > On Thu, 2023-02-16 at 09:56 -0500, Satish Patel wrote:
>>> >> >> Folks,
>>> >> >>
>>> >> >> I am running a small 3 node compute/controller with 3 node ceph
>>> storage
>>> >> in
>>> >> >> my lab. Yesterday, because of a power outage all my nodes went
>>> down.
>>> >> After
>>> >> >> reboot of all nodes ceph seems to show good health and no error
>>> (in ceph
>>> >> >> -s).
>>> >> >>
>>> >> >> When I started using the existing VM I noticed the following
>>> errors.
>>> >> Seems
>>> >> >> like data loss. This is a lab machine and has zero activity on vms
>>> but
>>> >> >> still loses data and the file system corrupt. Is this normal ?
>>> >> > if the vm/cluster hard crashes due to the power cut yes it can.
>>> >> > personally i have hit this more often with XFS then ext4 but i have
>>> >> > seen it with both.
>>> >> >>
>>> >> >> I am not using eraser coding, does that help in this matter?
>>> >> >>
>>> >> >> blk_update_request: I/O error, dev sda, sector 233000 op 0x1:
>>> (WRITE)
>>> >> flags
>>> >> >> 0x800 phys_seg 8 prio class 0
>>> >> >
>>> >> > you will proably need to rescue the isntance and repair the
>>> >> > filesystem of each vm with fsck
>>> >> > or similar. so boot with recue image -> repair filestem -> unrescue
>>> >> > -> hardreboot/start vm if needed
>>> >> >
>>> >> > you might be able to mitigate this somewhat by disableing disk
>>> >> > cacheing at teh qemu level but
>>> >> > that will reduce performance. ceph recommenes that you use
>>> >> > virtio-scis fo the device model and
>>> >> > writeback cach mode. we generally recommend that too however you can
>>> >> > use the disk_cachemodes option to
>>> >> > chage that.
>>> >> >
>>> >>
>>> https://docs.openstack.org/nova/latest/configuration/config.html#libvirt.disk_cachemodes
>>> >> >
>>> >> > [libvirt]
>>> >> > disk_cachemodes=file=none,block=none,network=none
>>> >> >
>>> >> > this curreption may also have happend on the cecph cluter side.
>>> >> > they have some options that can help prevent that via journaling
>>> wirtes
>>> >> >
>>> >> > if you can afford it i would get even a small UPS to allow a
>>> >> > graceful shutdown if you have future powercuts
>>> >> > to aovid dataloss issues.
>>> >>
>>> >>
>>> >>
>>> >>
>>> >>
>>>
>>>
>>>
>>>
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