dig MX toolserver.org gives:

;; ANSWER SECTION:
toolserver.org. 3600 IN MX 10 toolserver.org.

;; ADDITIONAL SECTION:
toolserver.org. 3600 IN A 208.80.155.197

telnet 208.80.155.197 smtp
Trying 208.80.155.197...
telnet: Unable to connect to remote host: Connection timed out

So no mailserver seems to be running there. How is this supposed to be configured?

Were you trying to connect to that host from within Labs? Then that's the intra-Labs public IP network issue.

But from the InterNet it doesn't look good either:

[tim@passepartout ~]$ nc -C 208.80.155.197 25
Ncat: Connection refused.
[tim@passepartout ~]$

So indeed there doesn't seem to be a mailserver running there (or connectible).

In T101656#1344489, @scfc wrote:

Were you trying to connect to that host from within Labs? Then that's the intra-Labs public IP network issue.

Yup, from somewhere on the internet.

Inside of labs it doesn't work either:

multichill@tools-bastion-01:~$ dig toolserver.org

; <<>> DiG 9.9.5-3ubuntu0.2-Ubuntu <<>> toolserver.org
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 25373
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:
;toolserver.org.                        IN      A

;; ANSWER SECTION:
toolserver.org.         3021    IN      A       10.68.16.162

;; Query time: 24 msec
;; SERVER: 208.80.154.20#53(208.80.154.20)
;; WHEN: Sun Jun 07 19:59:49 UTC 2015
;; MSG SIZE  rcvd: 48

multichill@tools-bastion-01:~$ telnet 10.68.16.162 smtp
Trying 10.68.16.162...
telnet: Unable to connect to remote host: Connection refused

This should be properly puppetized.

(tracked in https://phabricator.wikimedia.org/T85165)