On 2 Oct 2009, at 19:58, Jeremy Harris wrote:
> On 10/01/2009 08:56 PM, Paul Warren wrote:
>> 2. Does setting route_data to an A record with multiple IPs achieve
>> the redundancy I'm looking for? As far as I can tell, exim makes no
>> attempt to fall back on the second IP after the connection failure:
>> it
>> hadn't seen a connection failure on the other IP for around 3 hours
>> prior to going into "won't send any mail" mode.
>
> I think it probably doesn't do what you want; it does a single DNS
> lookup and tries one address. Could you use route_list with
> a dnsdb lookup and a string-edit to convert newlines to colons?
Ah, thanks.
I've switched to using:
route_list = * mx1.mythic-beasts.com:mx2.mythic-beasts.com
hosts_randomize
Which I think has the same effect as what you describe.
I'm sure I remember concluding that in other circumstances, Exim would
try each IP for a multi-homed host, but I now can't find documentation
of this behaviour other than this para:
"In all cases, if there are other hosts (or IP addresses) available
for the current set of addresses (for example, from multiple MX
records), they are tried in this run for any undelivered
addresses, ... "
(
http://www.exim.org/exim-html-current/doc/html/spec_html/ch45.html)
The above configuration certainly achieves a better balancing of load
between the two mx servers.
thanks,
Paul
