On 12/1/12 8:21 AM, Hermes Flying wrote:
> Thanks for your reply.
> First of all I didn't get if the VIP will migrate if Tomcat or load 
> balancer also fails. It will right?
If you configure Pacemaker correctly, yes.
> Also if I understand this correctly, I can end up with VIP on both 
> nodes if corosync fails due to network failure. And you suggest 
> redundant communication paths to avoid this.
> But if I understand the problem, if the VIP runs in my linux-1 and 
> pacemaker is somehow via corosync ready to take over on failure from 
> linux-2, if there is a network failure (despite redundant 
> communication paths, unless you guys recommend some specific topology 
> to the people using Pacemaker that you are 100% full proof) how can 
> you detect if the other node is actually crashed or just corosync 
> fails? In this case won't the linux-2 also "wakeup" to take VIP?
That is what fencing is for. If linux-1 goes offline from the 
perspective of linux-2, linux-2 will attempt to 
crash/power-cycle/power-off linux-1 to ensure it is really dead. Any 
resource previously running on linux-1 will be started on linux-2.

Usually with a two node config I take two NICs on each box and connect 
them directly to the other one - Also would work if you had two separate 
switches you could run each path through. Then I use Linux NIC bonding 
to provide redundancy and run corosync over the bond interface.
_______________________________________________
Linux-HA mailing list
[email protected]
http://lists.linux-ha.org/mailman/listinfo/linux-ha
See also: http://linux-ha.org/ReportingProblems

Reply via email to