[DRBD-user] Understanding degr-wfc-timeout
ag928272 at gideon.org
Mon Dec 6 17:26:22 CET 2010
On Mon, 06 Dec 2010 12:48:50 +0100, Lars Ellenberg wrote:
>> Starting drbd: Starting DRBD resources: [ drbd1 Found valid meta data
>> in the expected location, 16105058304 bytes into / dev/xvdb1.
>> d(drbd1) drbd: bd_claim(cfe1ad00,cc00c800); failed
>> [d108e4d0;c0478e79;1] 1: Failure: (114) Lower device is already
>> claimed. This usually means it is mounted.
> There. It cannot even attach.
> Because it cannot attach, it cannot read it's meta data. Thus it does
> not know anything about itself.
Ah! I noticed that, but it didn't click to me that this would be
related, so I just put that issue off.
>> [drbd1] cmd /sbin/drbdsetup 1 disk /dev/xvdb1 /dev/xvdb1 internal
>> --set- defaults --create-device failed - continuing!
> You better make sure xvdb1 is not used by someone else at the time your
> drbd tries to attach it.
> You may need to fix your fstab, or your lvm.conf, or your initrd, or
> whatever other "magic" is going on there.
LVM; the underlying device is being activated by LVM so I need to block
that. I'll make the change and try again.
>> FWIW, I've also posted in the thread "RedHat Clustering Services does
>> not fence when DRBD breaks" trying to understand the fencing process.
>> I think I managed to suspend all I/O in the case of a fence failure
>> (the handler returning a value of 6), but I'm not sure. Does:
>> 1: cs:WFConnection ro:Primary/Unknown ds:UpToDate/DUnknown C s----
>> ns:0 nr:0 dw:4096 dr:28 al:1 bm:3 lo:0 pe:0 ua:0 ap:0 ep:1 wo:b
>> indicate suspension? Is that what "s----" means?
> at that position, yes, that means application io is s: suspended, or r:
> you can manually resume with "drbdadm resume-io"
>> I've failed to find documentation for that bit of string in /proc/drbd.
> Is that so.
Yes. I would have thought it to be in
but if so then I'm missing it. Or is it elsewhere?
More information about the drbd-user