smtp/transport being filtered in private networking
I have a couple droplets in nyc2, and one of them is running postfix. However, if I try to connect to both ports 25 and 587 from another droplet through the private network interface, the connection times out. Nmap shows those ports ate being filtered (not by me though):
$ nmap XXX.XXX.XXX.XXX -p 25,587 Starting Nmap 6.46 ( http://nmap.org ) at 2014-08-22 14:26 UTC Nmap scan report for XXX.XXX.XXX.XXX Host is up (0.00044s latency). PORT STATE SERVICE 25/tcp filtered smtp 587/tcp filtered submission Nmap done: 1 IP address (1 host up) scanned in 1.26 seconds
Postfix is listening correctly:
# lsof -i tcp:25 COMMAND PID USER FD TYPE DEVICE SIZE/OFF NODE NAME master 4873 root 12u IPv4 11491 0t0 TCP *:smtp (LISTEN) master 4873 root 13u IPv6 11492 0t0 TCP *:smtp (LISTEN)
Just to be sure, I set postfix to listen in port 23, and was able to successfully connect:
$ telnet XXX.XXX.XXX.XXX Trying XXX.XXX.XXX.XXX... Connected to XXX.XXX.XXX.XXX. Escape character is '^]'. 220 Polibra ESMTP Postfix ^] telnet> q Connection closed.
Is that normal behavior?
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