relayhost set incorrectly on RHEL 7 about ansible-role-postfix

[benformosa]

I can see that this was changed in commit 9c1e8d9. I think it's a little unclear why the variable is specified as a yaml sequence/list, despite the usual use including brackets.
Postfix allows a few ways of specifying the relayhost (see man 5 postconf), which may include brackets or several other forms.

relayhost (default: empty)
The next-hop destination(s) for non-local mail; overrides non-local domains in recipient addresses. This information is overruled with relay_transport, sender_dependent_default_transport_maps, default_transport, sender_dependent_relayhost_maps and with the transport(5) table.

On an intranet, specify the organizational domain name. If your internal DNS uses no MX records, specify the name of the intranet gateway host instead.

In the case of SMTP or LMTP delivery, specify one or more destinations in the form of a domain name, hostname, hostname:port, [hostname]:port, [hostaddress] or [hostaddress]:port, separated by comma or whitespace. The form [hostname] turns off MX lookups. Multiple destinations are supported in Postfix 3.5 and later.

If you're connected via UUCP, see the UUCP_README file for useful information.

Examples:

relayhost = $mydomain
relayhost = [gateway.example.com]
relayhost = mail1.example:587, mail2.example:587
relayhost = [an.ip.add.ress]

I would suggest it might be better to specify postfix_relayhost as a string, and allow the user to set it to whatever value they want.

[robertdebock]

Hi, it's likely because "[" and "]" are characters that yaml interprets. I'll check what I can do, thanks for the report!