[cups-devel] systemd blocks port with cups 2.2.0

[Andreas Radke]

The cups 2.2.0 update lead to blocked addresses/port and webinterface access is forbidden.

E [22/Sep/2016:21:53:12 +0200] Unable to open listen socket for address 0.0.0.0:631 - Address already in use.
E [22/Sep/2016:21:53:12 +0200] Unable to open listen socket for address 192.168.1.90:631 - Address already in use.
E [22/Sep/2016:21:55:52 +0200] Unable to open listen socket for address [v1.::1]:631 - Address already in use.
E [22/Sep/2016:21:55:52 +0200] Unable to open listen socket for address 127.0.0.1:631 - Address already in use.
E [22/Sep/2016:21:55:52 +0200] Unable to open listen socket for address 192.168.1.90:631 - Address already in use.

cupsd.conf has worked well with all releases before.

Listen localhost:631
Listen 192.168.1.90:631
Listen /run/cups/cups.sock

A downgrade to cups 2.1.4 and server restart seems to free up the port and brings cups interface back and then updating to cups 2.2.0 also stays working. A reboot blocks it again.

root at server64:/root # ss -lpn|grep 631                                                                                                                        
tcp    LISTEN     0      128      :::631                  :::*                   users:(("cupsd",pid=1218,fd=4),("systemd",pid=1,fd=44))
root at server64:/root # lsof -i :631                                                                                                                            
COMMAND  PID USER   FD   TYPE DEVICE SIZE/OFF NODE NAME
systemd    1 root   44u  IPv6  11152      0t0  TCP *:ipp (LISTEN)
cupsd   1218 root    4u  IPv6  11152      0t0  TCP *:ipp (LISTEN)


Any idea what has changed in cups or is this a bug in systemd that now comes up?

-Andy
Arch Linux