[CentOS] high availability ideas

Sat Nov 19 11:11:11 UTC 2011
nux at li.nux.ro <nux at li.nux.ro>

Digimer writes:

> On 11/14/2011 09:41 AM, nux at li.nux.ro wrote:
>> Hi,
>> I'm looking for some recommendations. I need to have some sort of high 
>> availability for a set of php &  mysql web sites, they must be hosted on 2 
>> servers, in separate data centres and obviously on differrent IPs.
>> I can't use a load balancer because that will introduce a single point of 
>> failure making the "distributed setup" useless. I was thinking some sort of 
>> drbd/glusterfs/mysql-master-master replication and figure out how to make 
>> the dns system responsible with the fail over.
>> Am I going too far with this?
>> Thanks.
> WAN/Stretch clustering suffers most for network latency. If you need to
> keep the data in sync across both nodes, using DRBD will limit your hard
> drives, effectively, to the speed and latency of the link between your
> nodes at the different DCs. This is rarely usable.
> Stop by #linux-cluster and/or #drbd, I know there are folks there from
> Linbit and Hestaxo who could help you, but you're going to be facing
> rather expensive technical challenges. :)

Hello Digimer,

Thank you, however I decided to go for a less exotic setup and use a more 
passive way of sync (probably rsync and mysql replication) and I'll do 
the high availability part from DNS (yes, I know there are issues with this 
solution as well).

Thanks again.