Comment 4 for bug 1073520

Excerpts from James Page's message of 2012-12-03 14:01:29 UTC:
> Hi Ante
>
> More feedback post updates
>
> 1) dovecot-relation-joined
>
> #!/bin/bash
> set -eu
>
> myip=`unit-get private-address`
>
> relation-set imap-host=$my_ip pop-host=$myip
>
> Couple of comments here; the remote service will automatically be able
> to determine the IP address of the mail-stack-delivery service using:
>
> relation-get private-address
>
> This is implicit - so providing it over the relation explicitly is not
> required; However I would provide the ports for these services as
> relation data - for example:
>
> relation-set imap-port=143....
>

Note that one is not always intending to say "connect to me". Sometimes one
wants to say "connect to *that host*". So private-address, while convenient,
is not always required.