Re: [exim] Behaviour of randomize_hosts when some hostnames …

Top Page
Delete this message
Reply to this message
Author: Philip Hazel
Date:  
To: Adam Funk
CC: exim-users
Subject: Re: [exim] Behaviour of randomize_hosts when some hostnames have multiple IP addresses?
On Fri, 13 Apr 2007, Adam Funk wrote:

> If a router contains the following options:
>
>    route_list = * foo.example.com:mail.example.org
>    hosts_randomize

>
> and the dig command shows one "A" IP address for foo.example.com but
> two addresses for mail.example.org, is Exim
>
> * 50% likely to use foo.example.com and 25% likely to use each of
> mail.example.org's addresses,
> or
> * 33% likely to use each of the three?


It is 50% likely to use foo.example.com and 50% likely to use
mail.example.com. How it splits up the two addresses for
mail.example.com depends on how they are returned from the DNS (or
wherever) when it looks them up.

In other words, it randomizes the route_list before looking up the IP
addresses (for those items that need looking up).

-- 
Philip Hazel            University of Cambridge Computing Service
Get the Exim 4 book:    http://www.uit.co.uk/exim-book