FTP does not work in active mode: 425 Unable to build data connection: Connection timed out

Created:

2016-11-16 12:52:52 UTC

Modified:

2017-04-24 11:18:58 UTC

0

Was this article helpful?


Have more questions?

Submit a request

FTP does not work in active mode: 425 Unable to build data connection: Connection timed out

Applicable to:

  • Plesk 12.5 for Linux

Symptoms

  1. FTP does not work in active mode while accessing from external network:

    425 Unable to build data connection: Connection timed out
  2. FTP is accessible locally.

Cause

TCP port 20, which is used as FTP data port, is filtered by a firewall:

[root@external_server]# nmap -Pn 203.0.113.2 -p 20
Starting Nmap 6.47 ( http://nmap.org ) at 2016-05-14 02:41 NOVT
Nmap scan report for 203.0.113.2
Host is up.
PORT STATE SERVICE
20/tcp filtered ftp-data

Resolution

  1. Check firewall settings:

    # iptables -L -n | grep 20
  2. Allow incoming connections to the port:

    # iptables -I INPUT 1 -p tcp --dport=20 -j ACCEPT

    # service iptables save
  3. If the port is still being blocked, it is possible, that an intermediary firewall is filtering connections to the port. Contact network administrator regarding the issue.

Have more questions? Submit a request
Please sign in to leave a comment.