rpc.statd and avahi-daemon listening on all networks?

Question

Background:
- I'm running a home Debian GNOME desktop connected to the internet through an ethernet cable to an ethernet router.
- I have a printer connected directly to my PC with a USB cable.
- My PC has 2 hard drives.
- I occasionally copy pictures from my camera to my PC using a USB cable.

rpc.statd and avahi-daemon are listening on all networks and not only on 127.0.0.1 like cupsd and portmap.

I've read their man pages and various forums but I can't figure out if they are actually really needed. I mean, does GNOME need them ? Is portmap needed ? Is it possible to make them listen to 127.0.0.1 only ?

root@debian:/# netstat -nap | grep -v "unix"
Active Internet connections (servers and established)
Proto Recv-Q Send-Q Local Address  Foreign Address State   PID/Program name
tcp        0      0 127.0.0.1:111  0.0.0.0:*       LISTEN  168/portmap    
tcp        0      0 127.0.0.1:631  0.0.0.0:*       LISTEN  1594/cupsd      
tcp        0      0 0.0.0.0:42469  0.0.0.0:*       LISTEN  1180/rpc.statd  
tcp6       0      0 ::1:631        :::*            LISTEN  1594/cupsd      
udp        0      0 0.0.0.0:34406  0.0.0.0:*               1180/rpc.statd  
udp        0      0 0.0.0.0:5353   0.0.0.0:*               1536/avahi-daemon: 
udp        0      0 127.0.0.1:111  0.0.0.0:*               1168/portmap    
udp        0      0 0.0.0.0:42397  0.0.0.0:*               1536/avahi-daemon: 
udp        0      0 0.0.0.0:932    0.0.0.0:*               1180/rpc.statd  
udp        0      0 0.0.0.0:68     0.0.0.0:*               16068/dhclient  
udp6       0      0 :::5353        :::*                    1536/avahi-daemon: 
udp6       0      0 :::59211       :::*                    1536/avahi-daemon:

Answer 1

portmap and rpc.statd are old, probably going back to the early 90s at least. I believe the only thing they are still commonly used for is NFS, which is a way to map directories between *nix machines on a network. If you don't need that, you can uninstall them both.

avahi-daemon I'm not so sure about. I think it's used to find printers and other resources on a network? You can probably read about it on google, and if it's not something you need you can remove it.

Also, one of the great things about debian is that it will warn you if you try to uninstall something that is needed by other parts of your system. Debian package management is really nice. So if you find something you don't like, fire up aptitude and try to purge it. If it complains, just revert back to the original state.