[ClusterLabs] DRBD or SAN ?

[Ken Gaillot]

On 07/18/2017 09:34 AM, Lentes, Bernd wrote:
> 
> 
> ----- On Jul 17, 2017, at 11:51 AM, Bernd Lentes bernd.lentes at helmholtz-muenchen.de wrote:
> 
>> Hi,
>>
>> i established a two node cluster with two HP servers and SLES 11 SP4. I'd like
>> to start now with a test period. Resources are virtual machines. The vm's
>> reside on a FC SAN. The SAN has two power supplies, two storage controller, two
>> network interfaces for configuration. Each storage controller has two FC
>> connectors. On each server i have one FC controller with two connectors in a
>> multipath configuration. Each connector from the SAN controller inside the
>> server is connected to a different storage controller from the SAN. But isn't a
>> SAN, despite all that redundancy, a SPOF ?
>> I'm asking myself if a DRBD configuration wouldn't be more redundant and high
>> available. There i have two completely independent instances of the vm.
>> We have one web application with a databse which is really crucial for us.
>> Downtime should be maximum one or two hours, if longer we run in trouble.
>> Is DRBD in conjuction with a database (MySQL or Postgres) possible ?
>>
>>
>> Bernd
>>
> 
> Is with DRBD and Virtual Machines live migration possible ?

Yes, definitely. In the past, I've even live-migrated a VM with 24GB RAM
over 10gigE very quickly, with LVM over DRBD underneath.

> Bernd
>  
> 
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