Re: Remus : VM on backup not in pause state

[Dulloor <dulloor@gmail.com>]

On Thu, Jul 22, 2010 at 2:49 PM, Brendan Cully <brendan@cs.ubc.ca> wrote:
> On Thursday, 22 July 2010 at 13:45, Dulloor wrote:
>> My setup is as follows :
>> - xen : unstable (rev:21743)
>> - Dom0 : pvops (branch : stable-2.6.32.x,
>> rev:01d9fbca207ec232c758d991d66466fc6e38349e)
>> - Guest Configuration :
>> ------------------------------------------------------------------------------------------
>> kernel = "/usr/lib/xen/boot/hvmloader"
>> builder='hvm'
>> name = "linux-hvm"
>> vcpus = 4
>> memory = 2048
>> vif = [ 'type=ioemu, bridge=eth0, mac=00:1c:3e:17:22:13' ]
>> disk = [ 'phy:/dev/XenVolG/hvm-linux-snap-1.img,hda,w' ]
>> device_model = '/usr/lib/xen/bin/qemu-dm'
>> boot="cd"
>> sdl=0
>> vnc=1
>> vnclisten="0.0.0.0"
>> vncconsole=0
>> vncpasswd=''
>> stdvga=0
>> superpages=1
>> serial='pty'
>> ------------------------------------------------------------------------------------------
>>
>> - Remus command :
>> # remus --no-net linux-hvm <dst-ip>
>>
>> - On primary :
>> # xm list
>> Name                                        ID   Mem VCPUs      State   Time(s)
>> linux-hvm                                    9  2048     4     -b-s--     10.8
>>
>> - On secondary :
>> # xm list
>> Name                                        ID   Mem VCPUs      State   Time(s)
>> linux-hvm                                   11  2048     4     -b----      1.9
>>
>>
>> I have to issue "xm pause/unpause" explicitly for the backup VM.
>> Any recent changes ?
>
> This probably means there was a timeout on the replication channel,
> interpreted by the backup as a failure of the primary, which caused it
> to activate itself. You should see evidence of that in the remus
> console logs and xend.log and daemon.log (for the disk side).
>
> Once you've figured out where the timeout happened it'll be easier to
> figure out why.
>
Please find the logs attached. I didn't find anything interesting in
daemon.log.
What does remus log there ? I am not using disk replication, since I
have issues with that .. but that's for another email :)

The only visible error is in xend-secondary.log around xc_restore :
[2010-07-22 16:15:37 2056] DEBUG (balloon:207) Balloon: setting dom0 target to 5
765 MiB.
[2010-07-22 16:15:37 2056] DEBUG (XendDomainInfo:1467) Setting memory target of
domain Domain-0 (0) to 5765 MiB.
[2010-07-22 16:15:37 2056] DEBUG (XendCheckpoint:290) [xc_restore]: /usr/lib/xen
/bin/xc_restore 5 1 5 6 1 1 1 0
[2010-07-22 16:18:42 2056] INFO (XendCheckpoint:408) xc: error: Error
when reading pages (11 = Resource temporarily unavailabl): Internal
error
[2010-07-22 16:18:42 2056] INFO (XendCheckpoint:408) xc: error: error
when buffering batch, finishing (11 = Resource temporarily
unavailabl): Internal error

If you haven't seen this before, please let me know and I will try
debugging more.

-dulloor