[DRBD-user] DRBD over WAN Advisable?

Robinson, Eric eric.robinson at psmnv.com
Thu Mar 31 20:26:52 CEST 2011

Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.

> We've had a very similar setup (2 datacenters separated by 
> ~20 miles, no redundant heartbeat links) for several years.  
> The only time it caused any problems is when one of the main 
> switches in the secondary datacenter failed. 
> When the switch *came back up*, every DRBD cluster 
> split-brained and required manual intervention to get back to 
> a reasonable state.  Switch failures are pretty rare, though.

Good input. That's only a problem for 2-node clusters, right? We have a
couple of 3-node clusters, so quorum should prevent that I would think?

> > Is there a way to minimize the risk of split-brain over WAN?
> If it's switch failure you're looking to guard against, put a 
> quorum server that's in a third datacenter into your cluster 
> management config.  That
> *should* fix that particular problem, since the machine that 
> can't see the quorum server or its peer should release all 
> its resources.  It makes things more complicated, though, 
> since you need yet another machine that's in yet another 
> place.  

Okay, I see we're thinking along the same lines... But why would the
quorum server need to be in a third data center? The stranded server in
the secondary data center would release its resources, while the two
servers that can still talk to eachother in the primary data center
should be fine, right?


Disclaimer - March 31, 2011 
This email and any files transmitted with it are confidential and intended solely for Matt Graham,drbd-user at lists.linbit.com. If you are not the named addressee you should not disseminate, distribute, copy or alter this email. Any views or opinions presented in this email are solely those of the author and might not represent those of Physicians' Managed Care or Physician Select Management. Warning: Although Physicians' Managed Care or Physician Select Management has taken reasonable precautions to ensure no viruses are present in this email, the company cannot accept responsibility for any loss or damage arising from the use of this email or attachments. 
This disclaimer was added by Policy Patrol: http://www.policypatrol.com/

More information about the drbd-user mailing list