DNS load balancing

[Kenneth Marshall]

On Tue, May 11, 2010 at 09:35:26AM -0300, Andre Nathan wrote:
> Hello
> 
> I'm setting up a two-machine cyrus cluster using OCFS2 over DRBD. The
> setup is working fine, and I'm now considering the load balancing
> options I have.
> 
> I believe the simplest option would be to simply rely on DNS load
> balancing. However, for this to work, I need to consider what happens
> when one of the cluster nodes fails, regarding the clients which access
> the cluster:
> 
>  - Will IMAP and POP3 clients automatically try the second DNS entry if 
>    connecting to the first one fails?
>  - Will the LMTP client also do this? I'm using the postfix LMTP client 
>    for delivery.
> 
> Does any one have experience with this kind of setup?
> 
> Thanks in advance,
> Andre
> 
Hi Andre,

Most mail clients will provide a very poor user experience for failover
with DNS load balancing. Almost any other option would be a better choice
although not as simple to implement.

Regards,
Ken