[DRBD-user] Split Brain again, during reboot

[Ben Clewett]

Laurent,

I haven't found a solution to my split-brain problem, but I have found a 
work-around which may be useful to other users.

Heartbeat and drbd were being started and stopped in the wrong order, as 
heartbeat does not regard drbd as a dependency, and the default order is 
alphabetical:

# cd /etc/..../rc5.d
# ls | grep drbd
K12drbd
S10drbd
# ls | grep heartbeat
K12heartbeat
S10heartbeat

The problem seems to be drbd stopping, before heartbeat executes the 
'umount' and 'Secondary'.

This is a repeatable failure on my servers, it tends to cause 
split-brain most times, requiring the loss of a disk's data:

kernel: drbd0: Handshake successful: DRBD Network Protocol version 86
kernel: drbd0: Split-Brain detected, dropping connection!
kernel: drbd0: self 
E34C568E597A770D:1C06E391A1E5477E:E87538E5DA462E1E:56F445DB49EBD97F
kernel: drbd0: peer 
8F0799656A81A283:1C06E391A1E5477F:E87538E5DA462E1E:56F445DB49EBD97F
kernel: drbd0: conn( WFReportParams -> Disconnecting )

However, if I change the order then I have a work-around for my 
split-brain.  Problem solved.

I hope this is of some use to other users.

Ben



Laurent CARON wrote:
> Ben Clewett wrote:
>>
>> Hi Guys,
>>
>> (Sorry if multiple postings, having problems with email)
>>
>> Sometime during the last few days my DRBD (8.0.3) entered a split-brain.
>>
>> I am not sure what caused it, and wonder whether there are any experts
>> on reading logs who might be able to help me?
>>
>> Starting from a good state, I requested a /sbin/reboot:
>>
> 
> Hi,
> 
> Can you please post the output of cat /proc/drbd ?
> 
> Thanks
> 


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