MX Record question

[pixelpadre]

Kick this around.

Lately google has been really strict about mx records and even diverting good mail to spam folder based on mx records.

If zc is using sendmail and not smtp, the mail relay shows the sender as server.myserver.com. If I have no mx records for server.myserver.com, would that piss off google?

[DrByte]

Short answer: It's complicated.

Technically the answer should be "no".

But Google et al use all kinds of combined indicators to do their thing.

1. MX is for "incoming mail", not outgoing. So in the purest sense it shouldn't matter.
But, to your point, it's certainly easier for Google to ascertain whether a message is spammy if the MX is the same as the sending server. eg: it's much less likely to be spam if it's the only place where emails happen, both inbound and outbound.

Still, it shouldn't be necessary.
That said, if you're into experimenting, you could set your webserver to be a fallback MX record and test whether spam happens as much after that. The downside is that you might lose mail if the mta network actually chooses your webserver to attempt to deliver mail to it ... which could result in bounces, and if Google/Yahoo discover bounces to your domain then they instantly start flagging your emails as possibly untrustworthy. It's a delicate dance.

2. SPF technically determines what servers are allowed to "send" emails for the domain. As long as it includes "A" for your server's A record, or at least the server's IP address, then it should be fine. You may want to tweak the ~all suffix to -all once you've determined all the configuration is correct, but that's "advanced".

3. Using "sendmail" is sometimes seen as "less authority" if the sendmail server isn't setting "authentication headers" in the outbound email. This is where switching to SMTPAUTH is usually recommended since by providing the username/pwd for the account on the email server will result in that server setting auth headers that indicate the email message has gone through an authentication step. But if you've got the skill to configure sendmail so that the messages are properly notated as authenticated then you should be fine. Most DIY folks don't do this and end up in the spam trap.

4. And DKIM/DomainKeys/DMARC should be configured for your domain as well. This includes setting things in DNS to match the keys configured in your sendmail server and any other servers handing inbound and outbound email for your domain.

[pixelpadre]

Well I'm glad to know that my question actually had some merit. The problem was not with zc, it was with osclass. But the situation could apply to zc as well. Although I havent tried to see if gmail is diverted to spam when using zc. I might do that just for my own curiosity.

Email tweaking is getting really nasty. There are too many variables as you mentioned above. And it's only going to get worse.

[plc613]

Well I'm glad to know that my question actually had some merit. The problem was not with zc, it was with osclass. But the situation could apply to zc as well. Although I havent tried to see if gmail is diverted to spam when using zc. I might do that just for my own curiosity.

Email tweaking is getting really nasty. There are too many variables as you mentioned above. And it's only going to get worse.

You really should implement one of the reputable methods. The only downside is the time to do it.