[ClusterLabs] DRBD or SAN ?

[Digimer]

On 2017-07-18 01:41 PM, Lentes, Bernd wrote:
> 
> 
> 
>>>>
>>>
>>> Is with DRBD and Virtual Machines live migration possible ?
>>>
>>>
>>> Bernd
>>
>> yes, but dual-primary is needed (this is how the Anvil! does live
>> migration). With DRBD 9, you can set it up to momentarily do
>> dual-primary to support live migration, though I have not used this
>> myself yet.
>>
>> With dual-primary, you need to be sure a few things are in place (ie:
>> proper fencing, but you need that anyway, a cluster resource manager, etc).
>>
> 
> On SLES 11 SP4 HAE DRBD 8.4 is available. Do i need a cluster fs on top of a dual primary DRBD ?
> I assume.
> 
> 
> Bernd

Depends.

If you want to have a shared FS, yes. If you want to back VMs though, we
use clustered LVM to manage the DRBD space, creating per-VM LVs, and
then use the resource manager to manage the servers. This keeps the LVM
data in sync and avoids the cost of cluster locking.

-- 
Digimer
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