Server Fault is a question and answer site for system and network administrators. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I've got my own domain name with my (CentOS 6.4) Linux box running as primary MX (two back-up MX off site). At home, I can get to my mail server from Thunderbird on my LAN, since sending the password across the wire in plain isn't an issue.

Away from home, I use either's webmail solution, or if I want to 'go retro', I ssh in and run mutt.

Everyone's happy, except my iPhone. I cannot get the iPhone to connect to my mail server, so I'm guessing it's port-related, or SSL ?

My apache server has SSL certificates, but I'm guessing that it's a different set of certs for sendmail?

Can someone help?

share|improve this question

Sendmail can use the same SSL certificates as Apache, so no problem there as long as both are addressed by the same hostname. Simply configure SSL in the and regerate the

For remote usage you may want to configure sendmail to listen to listen to either ports 587 (mail submission) or 465 (smtps) as in many networks outgoing traffic on the default smtp port 25 is blocked.

While you're doing that you may also want to configure SMTP authentication, and possibly with the same certificates an SSL enabled IMAP server...

share|improve this answer
I went overboard answering another question once where I detailed the whole setup of sendmail SSL and SMTPAUTH for CentOS and RHEL. – HBruijn Nov 29 '13 at 13:51
Is this OK?… Note that the certs I have are filename.crt, filename.csr and filename.key. So does the fact that that site list a filename.pem change things? – user27880 Nov 29 '13 at 13:59
The filename extention in Linux is mostly unimportant although some conventions exists. As long as filename.crt contains your (self-) signed certificate in PEM encoding it should work, which is the reason most examples would use filename.pem. – HBruijn Nov 29 '13 at 14:48

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.