Re: I/O errors after migration - why?

[Tomasz Chmielewski <mangoo@wpkg.org>]

Tomasz Chmielewski schrieb:
> Tomasz Chmielewski schrieb:
>> Tomasz Chmielewski schrieb:
>>> I'm trying to perform live migration by following the instructions on 
>>> http://www.linux-kvm.org/page/Migration.
>>> Unfortunately, it doesn't work very well - guest is migrated, but 
>>> looses access to its disk.
>>>
>>> On the destination host, I'm starting the guest with exactly the same 
>>> options as on the source host, with "-incoming tcp:0:4444".
>>> On the source host, I start the migration with "migrate -d tcp:B:4444".
>>>
>>> Both hosts use the same iSCSI device and can access it.
>>>
>>> Looks like the destination host can't really access the iSCSI device 
>>> after all? No - after I reboot the guest (echo b > 
>>> /proc/sysrq-trigger), it boots just fine from its disk. Also lsof on 
>>> the host shows that the kvm process accesses the correct /dev/sdX 
>>> device.
>>
>> Similar symptoms with virtio_blk (i.e., when guest is booted off a 
>> live CD and tries to access the disk after migration).
>>
>> The only difference between SCSI and virtio_blk is that SCSI signals 
>> errors and aborts, and virtio_blk waits forever and doesn't give a clue.

That is interesting (or not?).

In monitor, after migration, "info block" says:

scsi0-hd0: type=hd ...

Before migration, it was:

virtio0: type=hd ...

?

On both sides the guest was started with the same option (delta 
"-incoming...").

-- 
Tomasz Chmielewski
http://wpkg.org