I run my personal email and web on an old Sun Cobalt 550 server installed with Strongbolt (CentOS) Linux. It’s a good way to use end of life hardware but with a current Linux OS that has a small physical form factor and is easy to manage. My server automatically updates itself via yum but every now and then an error crops up with proftpd following an automatic update. My monitoring of the FTP port will go crazy and I will not be able to connect via FTP.

It’s no use trying to restart proftpd via the init script because it is an xinetd service. The following will occur whether xinetd is working properly or not:

[root@jenna ~]# /etc/rc.d/init.d/proftpd restart
Shutting down proftpd: [FAILED]
Starting proftpd: jenna – fatal: Socket operation on non-socket
[FAILED]

However, most people will try the above first because they’re used to using init scripts and a quick Google will reveal lots of people set to use xinetd but then told to swap config. That is not the correct course of action on a Cobalt box installed with Strongbolt because the system is meant to be using xinetd.

Strongbolt / CentOS uses xinetd for proftp and the automatic updates disable the xinetd settings:

[root@jenna ~]# cd /etc/xinetd.d/

[root@jenna xinetd.d]# vi xproftpd

Change this line:

disable                 = yes

To:

disable                 = no

Now restart xinetd:

[root@jenna xinetd.d]# /etc/rc.d/init.d/xinetd restart

That has mostly solved the problem for me before although I once had a completely blank xproftpd file in the same directory so had to restore from the xproftpd.rpmsave, which was in the same directory.