[ClusterLabs] Adding 'virsh migrate migrate-setspeed' support to the vm RA

[Digimer]

On 14/09/15 07:19 AM, Dejan Muhamedagic wrote:
> Hi Digimer,
> 
> On Fri, Sep 04, 2015 at 03:36:09AM -0400, Digimer wrote:
>> Hi all,
>>
>>   I hit an issue a little while ago where live-migrating a VM (on the
>> same management network normally used for corosync and a few other
>> monitoring tasks) ate up all the bandwidth, causing corosync to declare
>> a failure and triggering a fence.
>>
>>   I've dealt with this, in part, by adding redundant ring support on a
>> different network. However, I'd like to also limit the migration
>> bandwidth so that I don't need to fail over the ring in the first place.
> 
> As you certainly know, heavy traffic networks are not well suited
> for the latency sensitive cluster communication. Best to have the
> two separated.

Oh for sure, but I've already hit 6 NICs per node (back-channel,
normally just corosync, storage dedicated to DRBD and internet-facing
dedicated to the user app). Adding two more NICs just for live
migration, which happens very rarely, is hard to justify, despite this
issue. If I can't reliably solve it with this (and/or tc and/or rrp...)
then I will revisit this option.

>>   Is it reasonable/feasible to add 'virsh migrate-setspeed' support to
>> the vm.sh RA? Something like; 'setspeed="75MiB"'?
> 
> Yes, sounds like a good idea. Care to open an issue in github?
> 
> Thanks,
> 
> Dejan

Done.

https://github.com/ClusterLabs/resource-agents/issues/679

-- 
Digimer
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