trouble with postfix install (timing out from client)

Question

I have just outfitted a basic server (Ubuntu 12.04 LTS /Precise Pangolin) and have installed Postfix and Dovecot, based on the Ubuntu manuals.

https://help.ubuntu.com/community/Dovecot

https://help.ubuntu.com/community/Postfix

Postfix gets mail out of the box to my gmail account, e.g.:

sendmail [redacted]@gmail.com < /etc/motd

Testing remote access with the open source client for Eudora, I can successfully download email, so Dovecot/POP3 seems to be functioning.

However, I cannot seem to get Eudora to send email from my local computer. Depending on the security/port config I use, it generally times out.

I seem to be able to get access via the local terminal, and remote shells, such as (from a remote server):

$ telnet lists.teachers.net 25
Trying 50.56.184.186...
Connected to lists.teachers.net.
Escape character is '^]'.
220 lists.teachers.net ESMTP Postfix (Ubuntu)
ehlo lists.teachers.net
250-lists.teachers.net
250-PIPELINING
250-SIZE 10240000
250-VRFY
250-ETRN
250-STARTTLS
250-AUTH PLAIN LOGIN
250-AUTH=PLAIN LOGIN
250-ENHANCEDSTATUSCODES
250-8BITMIME
250 DSN
quit
221 2.0.0 Bye
Connection closed by foreign host.

I tried setting Eudora to use STARTTLS, SSL/TLS, and none, but they all time out. When Eudora tries to connect, i don't see any activity in the /var/log/mail/log or /var/log/mail.err , which I guess means those aren't the relevant logs or there is no activity to report.

I haven't set up any firewall rules:

$ sudo iptables -L
Chain INPUT (policy ACCEPT)
target     prot opt source               destination

Chain FORWARD (policy ACCEPT)
target     prot opt source               destination

Chain OUTPUT (policy ACCEPT)
target     prot opt source               destination

netstat output:

$ sudo netstat -tap
Active Internet connections (servers and established)
Proto Recv-Q Send-Q Local Address           Foreign Address         State       PID/Program name
tcp        0      0 *:submission            *:*                     LISTEN      4112/master
tcp        0      0 *:pop3                  *:*                     LISTEN      3210/dovecot
tcp        0      0 *:imap2                 *:*                     LISTEN      3210/dovecot
tcp        0      0 *:ssh                   *:*                     LISTEN      564/sshd
tcp        0      0 *:smtp                  *:*                     LISTEN      4112/master
tcp        0      0 *:imaps                 *:*                     LISTEN      3210/dovecot
tcp        0      0 *:pop3s                 *:*                     LISTEN      3210/dovecot
tcp        0    300 lists.teachers.net:ssh  99-95-169-159.lig:55464 ESTABLISHED 1433/sshd: listman
tcp6       0      0 [::]:submission         [::]:*                  LISTEN      4112/master
tcp6       0      0 [::]:pop3               [::]:*                  LISTEN      3210/dovecot
tcp6       0      0 [::]:imap2              [::]:*                  LISTEN      3210/dovecot
tcp6       0      0 [::]:ssh                [::]:*                  LISTEN      564/sshd
tcp6       0      0 [::]:smtp               [::]:*                  LISTEN      4112/master
tcp6       0      0 [::]:imaps              [::]:*                  LISTEN      3210/dovecot
tcp6       0      0 [::]:pop3s              [::]:*                  LISTEN      3210/dovecot

MX record:

$ dig mx lists.teachers.net

; <<>> DiG 9.8.1-P1 <<>> mx lists.teachers.net
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 22244
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 2, ADDITIONAL: 3

;; QUESTION SECTION:
;lists.teachers.net.            IN      MX

;; ANSWER SECTION:
lists.teachers.net.     300     IN      MX      100 lists.teachers.net.

;; AUTHORITY SECTION:
teachers.net.           2057    IN      NS      dns1.stabletransit.com.
teachers.net.           2057    IN      NS      dns2.stabletransit.com.

;; ADDITIONAL SECTION:
lists.teachers.net.     300     IN      A       50.56.184.186
dns1.stabletransit.com. 77665   IN      A       69.20.95.4
dns2.stabletransit.com. 77741   IN      A       65.61.188.4

;; Query time: 830 msec
;; SERVER: 72.3.128.241#53(72.3.128.241)
;; WHEN: Thu Jan 10 14:08:34 2013
;; MSG SIZE  rcvd: 155

How can I troubleshoot this, maybe from a remote machine? What logs might shed light? What other info would be helpful here? Thanks!

Answer 1

The connection attempt should be visible in /var/log/mail.log -> this sounds like a client side issue.

try telnetting the server on port 25 from the box where eudora is running. if that times out as well:

• check if your provider blocks port 25 outgoing. if it does, enable the submission port (587) instead, it's a good practice anyway to separate MUA-MTA from MTA-MTA ports.

• check if a locally installed firewall or antivirus software interferes with smtp traffic. I've seen AV software being the culprit of connection issues a lot.