Re: [exim] Load Balancing (2) Exim servers

--On 8 November 2007 14:13:02 -0500 JDavila@??? wrote:

>
> Hi Exim Friends,
>
> How can I load balance (2) Exim servers for Inbound and OutBound
> Deliveries. Any info will be much appreciated.

The simplest method is to make the two servers equal priority in your MX
records. You'll get load balanced to within about 10 to 15% of optimal.
Alternatively, you can offer a single MX record pointing to a round robin A
record.

For outbound, your mail clients will be configured to access a single
domain. Make that domain a Round Robin DNS pointing to two IP addresses.

Ideally, you should keep your MX IP addresses different from your message
submission IP addresses, so that you can distinguish between inbound and
outbound domains. It's pretty easy to arrange this just by changing your MX
records.

Assuming that we're talking about servers for languageworks.com, you have
this set up:

chip-74 % host languageworks.com
languageworks.com has address 209.218.206.60
languageworks.com mail is handled by 0 nyclns01.languageworks.com.
languageworks.com mail is handled by 10 nyclns04.languageworks.com.
chip-75 % host nyclns01.languageworks.com
nyclns01.languageworks.com has address 209.218.206.60
chip-76 % host nyclns04.languageworks.com
nyclns04.languageworks.com has address 209.218.206.68

Just change the MX records so that both servers have the same priority (and
are configured the same way).


--
Ian Eiloart
IT Services, University of Sussex
x3148