[CentOS] Load balancing email?

[Benjamin Smith]

Using multiple A records is good for performance balancing, but what if one of 
the systems fails? 

Using your cocnfiguration, the delivering mail server has an "a" record and a 
single MX, so it wouldn't try the other mail server in the case of a failure, 
right? 

Whereas, by listing multiple IPs and mx1/mx2, wouldn't the delivering mail 
server try the other address? 

Thanks, 

-Ben 

On Tuesday 25 October 2005 16:02, you wrote:
> I once did this and it worked great:
> 
>      IN    MX    10 mx.example.com.
> 
> mx   IN    A    192.168.1.1
>      IN    A    192.168.1.2
> 
> ...etc.  Perfect DNS load balancing.
> 
> Jack
> 
> Benjamin Smith wrote:
> 
> >Currently, we have two mail relays for inbound messages, and a third for 
POP.
> >
> >The inbound messages go thru all the CPU-intensive anti-spam stuff, and 
then
> >they relay it to the POP server for pickup.
> >
> >Currently, one of these is the "primary", and the other is "secondary", and
> >I'd like them to be considered more or less as equals, since the "primary"
> >system is getting beaten pretty hard.
> >
> >The DNS zone file says something like this:
> >
> >###############################
> >@isp.com
> ><SNIP>
> >                IN      MX      100 mx1.isp.com.
> >                IN      MX      1100 mx2.isp.com.
> ><SNIP
> >################################
> >
> >I seem to recall that I make them act as "equals" by simply changing this 
to
> >
> >###############################
> >@isp.com
> ><SNIP>
> >                IN      MX      100 mx1.isp.com.
> >                IN      MX      100 mx2.isp.com.
> ><SNIP
> >################################
> >
> >so that they both get about the same amount of inbound messages. Has 
anybody
> >here actually done this? How well does this work as far as failover if 
either
> >system fails?
> >
> >-Ben
> >--
> >"The best way to predict the future is to invent it."
> >- XEROX PARC slogan, circa 1978
> >_______________________________________________
> >CentOS mailing list
> >CentOS at centos.org
> >http://lists.centos.org/mailman/listinfo/centos
> >  
> >
> 

-- 
"The best way to predict the future is to invent it."
- XEROX PARC slogan, circa 1978