So I set-up postfix for email according to the tutorial. I have the FQDN set at mydomain.com since I'm only running one website (wordpress).

My A Record point to my linode's IP and my website works.
My MX record currently looks like:
10 @ mydomain.com
0 @ smtp.secureserver.net

I opened a ticket and they said that my two lines:
postconf -e 'myhostname = server.yourdomain.com'
postconf -e 'mydestination = server.yourdomain.com, localhost, localhost.localdomain'

Were wrong - so I fixed that. They also said that they used telnet to test my mail server.

How would one do this to make sure I fixed the issue?

Also, I am using a mail client (simple mail plugin for firefox). I have

POP3 mydomain.com port 110
login: user+mydomain.com
SMTP mydomain.com port 26
login: user+mydomain.com

Is this correct? I guess the better question is how can I find out if this is correct?

Google "telnet mail server" for examples.



Depending on your sasl backend and config, it could be + or @. I use Dovecot, both for POP3 and SMTP auth (sasl backend to postfix), and with that I use full email as username (@). Also, test by trying it out.

Try sending email without authorizing (say, via telnet) to a domain not hosted on your server to see if you have open relay.

BTW, smtp should be at port 25.

Thanks - I did Google a bit but your search query pulled up what I needed perfectly.

Well I tried telnetting to mydomain.com port 25 and all I got was a blank screen so I suppose that means it's still not working properly.
I can telnet localhost 25 as root and although it comes up it doesn't look like it does here (http://www.yuki-onna.co.uk/email/smtp.html)

When I do port 110 I get a +OK hello there. Not sure if that's even relevent...

I used port 26 because that's how all my other sites (hosted on cpanel shared hosting) have been set-up. But port 25 still doesn't work (see above).

Any suggestions on how to proceed?

Well, you can use port 26 if you plan to use the server for outgoing mails only (so you configure mail client to connect @ 26), but for incoming mail, other MTAs expect port 25.

If you can't telnet to port 25 from outside, but it does work locally, it means either postfix is listening on wrong IP, does not listen at all, or you have a firewall blocking port 25.

If you get +OK @ 110, it means your POP3 server (which is not postfix) is accepting connections.

Can you post or pastebin the output of postconf -n (redact any private data, like your domain name if you wish)? I'm not an expert with Postfix, but I can do get one configured for my purposes (virtual addresses), and I'll try to help, but the output will certainly be of use to someone who can recognize your problem at once.

Thanks for looking at this. Setting up apache was easier since I could flounder my way through that. I really have no idea with this stuff...

alias_database = hash:/etc/aliases
alias_maps = hash:/etc/aliases
append_dot_mydomain = no
biff = no
broken_sasl_auth_clients = yes
config_directory = /etc/postfix
html_directory = /usr/share/doc/postfix/html
inet_interfaces = all
mailbox_size_limit = 0
message_size_limit = 30720000
mydestination = mydomain.com, localhost, localhost.localdomain
myhostname = mydomain.com
mynetworks = 127.0.0.0/8
myorigin = /etc/mailname
proxy_read_maps = $local_recipient_maps $mydestination $virtual_alias_maps $virtual_alias_domains $virtual_mailbox_maps $virtual_mailbox_domains $relay_recipient_maps $relay_domains $canonical_maps $sender_canonical_maps $recipient_canonical_maps $relocated_maps $transport_maps $mynetworks $virtual_mailbox_limit_maps
readme_directory = /usr/share/doc/postfix
recipient_delimiter = +
relayhost =
smtp_tls_session_cache_database = btree:${data_directory}/smtp_scache
smtpd_banner = $myhostname ESMTP $mail_name (Ubuntu)
smtpd_recipient_restrictions = permit_mynetworks, permit_sasl_authenticated, reject_unauth_destination
smtpd_sasl_auth_enable = yes
smtpd_sasl_authenticated_header = yes
smtpd_tls_cert_file = /etc/postfix/smtpd.cert
smtpd_tls_key_file = /etc/postfix/smtpd.key
smtpd_tls_session_cache_database = btree:${data_directory}/smtpd_scache
smtpd_use_tls = yes
virtual_alias_domains =
virtual_alias_maps = proxy:mysql:/etc/postfix/mysql-virtual_forwardings.cf, mysql:/etc/postfix/mysql-virtual_email2email.cf
virtual_gid_maps = static:5000
virtual_mailbox_base = /home/vmail
virtual_mailbox_domains = proxy:mysql:/etc/postfix/mysql-virtual_domains.cf
virtual_mailbox_maps = proxy:mysql:/etc/postfix/mysql-virtual_mailboxes.cf
virtual_uid_maps = static:5000

And you have no errors in the log on postfix startup? Firewall blocking port 25?

Just to throw out another option - why host your own mail server?

Google Apps is free for 50 users or less, has excellent built in spam filtering, can be accessed via pop3, imap4, or secure webmail, and each mailbox has 7 gig of space, AND you get Google Doc's built-in for document sharing.

I haven't run my own mailserver for small domains for several years since Google Apps came out (of course we still do for bigger inhouse servers and those that need a intranet as well as internet mail solution).

Besides not having to install/configure/manage/monitor it (and you definately don't want a unsecured mail server - it will get your IP and maybe your Linode neighbors IP blacklisted in a minute) it doesn't eat up any space or bandwidth on your VPS.

So take a peek, it might save you a lot of headaches.

http://www.google.com/apps/intl/en/group/index.html