SMTP port forwarding fail

[ps.02]

(Reposting here after support robot told me helpdesk is not for free accounts. I do have a free (legacy) account, but I've bought some credits in case SMTP port forwarding requires them.)
(ETA: redacted domain after Sandy took it back to the ticket.)

I tried setting up SMTP port forwarding for [redacted]:

@ 300 MX 5 wire.example.com:26

This appeared to work, setting an external MX record, but when I send a test mail, mx-caprica accepts it but then fails to actually deliver to my mail server on port 26.

I had to revert it before I started losing real mail, so I've set up a test subdomain:

wire 900 MX 5 wire.example.com:26

Same symptoms: mx-caprica accepts my test mail, but I never see it delivered.

(Addendum: some earlier test emails did get delivered after I reverted my MX change: mx-caprica delivered them through my old MX. But I never saw actual SMTP port forwarding work.)

 

[sandy]

replied to your support ticket. thanks
sandy

 

[ps.02]

Followup for the Googles: they resolved my issue. For technical reasons I won't get into here, if you use this feature, you can't have an MX record pointing to its own hostname, e.g., wire.example.com MX 5 wire.example.com:26.

 

[sandy]

so they would require something like:


example.com MX 5 wire.example.com:26. ?

thanks
sandy

 

[ps.02]

Correct. The main thing is that if your MX points to wire.example.com:26, then you shouldn't also have a MX record for wire.example.com itself.

 

[sandy]

ahh thanks for this

sandy