Listening ports (more than one)

[sopadeajo]

What is the purpose of all those listening ports?

Note than this information (scary for me) was gotten with the good-old terminal (not with the unjustly accused Firestarter

-desktop:~$ netstat -al | grep LISTEN
tcp 0 0 localhost:ipp *:* LISTEN
tcp6 0 0 localhost:ipp [::]:* LISTEN
unix 2 [ ACC ] STREAM LISTENING 7247 /var/run/avahi-daemon/socket
unix 2 [ ACC ] STREAM LISTENING 7039 @/org/bluez/audio
unix 2 [ ACC ] STREAM LISTENING 6310 @/var/run/hald/dbus-HPv96rko3u
unix 2 [ ACC ] STREAM LISTENING 7137 @/tmp/.X11-unix/X0
unix 2 [ ACC ] STREAM LISTENING 6245 /var/run/dbus/system_bus_socket
unix 2 [ ACC ] STREAM LISTENING 7022 /var/run/sdp
unix 2 [ ACC ] STREAM LISTENING 6040 /var/run/acpid.socket
unix 2 [ ACC ] STREAM LISTENING 7138 /tmp/.X11-unix/X0
unix 2 [ ACC ] STREAM LISTENING 8248 /tmp/keyring-PRGAIN/socket
unix 2 [ ACC ] STREAM LISTENING 10460 /tmp/ssh-EeEmIN3489/agent.3489
unix 2 [ ACC ] STREAM LISTENING 11029 /tmp/orbit-/linc-f56-0-5a0188ef472e5
unix 2 [ ACC ] STREAM LISTENING 11279 /tmp/orbit-/linc-f54-0-1b29369261395
unix 2 [ ACC ] STREAM LISTENING 11289 /tmp/.esd-1000/socket
unix 2 [ ACC ] STREAM LISTENING 11292 /home//.pulse/7ec17fb8b2078fff5cb60dad4aa7205c:runtime/native
unix 2 [ ACC ] STREAM LISTENING 11332 /tmp/seahorse-AZI8qL/S.gpg-agent
unix 2 [ ACC ] STREAM LISTENING 11371 /tmp/.ICE-unix/3489
unix 2 [ ACC ] STREAM LISTENING 11395 /tmp/orbit-/linc-da1-0-11054d126ac20
unix 2 [ ACC ] STREAM LISTENING 11433 /tmp/orbit-/linc-f61-0-119fe838dc4ec
unix 2 [ ACC ] STREAM LISTENING 7094 /var/run/gdm_socket
unix 2 [ ACC ] STREAM LISTENING 11563 /tmp/orbit-/linc-f72-0-33e0abf73dc23
unix 2 [ ACC ] STREAM LISTENING 11587 /tmp/orbit-/linc-d84-0-5aab58a48b7e
unix 2 [ ACC ] STREAM LISTENING 11591 /tmp/keyring-PRGAIN/socket.ssh
unix 2 [ ACC ] STREAM LISTENING 11593 /tmp/keyring-PRGAIN/socket.pkcs11
unix 2 [ ACC ] STREAM LISTENING 11726 /tmp/orbit-/linc-f7a-0-6d20b2aa43079
unix 2 [ ACC ] STREAM LISTENING 11742 /tmp/orbit-/linc-f79-0-21b0d7f5b075d
unix 2 [ ACC ] STREAM LISTENING 16595 @/tmp/dbus-1uANDDQL10
unix 2 [ ACC ] STREAM LISTENING 12301 /tmp/orbit-/linc-f8b-0-4029bcaf164ff
unix 2 [ ACC ] STREAM LISTENING 12467 /tmp/orbit-/linc-f7f-0-5e75ce598f6cd
unix 2 [ ACC ] STREAM LISTENING 12589 /tmp/orbit-/linc-f7b-0-9d90c5f42ae
unix 2 [ ACC ] STREAM LISTENING 12808 /tmp/orbit-/linc-f7d-0-3425265b84c31
unix 2 [ ACC ] STREAM LISTENING 12490 /tmp/orbit-/linc-f80-0-5e75ce59957b0
unix 2 [ ACC ] STREAM LISTENING 12495 /tmp/orbit-/linc-f82-0-752404f795c1e
unix 2 [ ACC ] STREAM LISTENING 12601 /tmp/orbit-/linc-f8e-0-552adcc167d2
unix 2 [ ACC ] STREAM LISTENING 12630 /tmp/orbit-/linc-f9c-0-12a3b57829aeb
unix 2 [ ACC ] STREAM LISTENING 12665 /tmp/orbit-/linc-f83-0-3ae806cba23b1
unix 2 [ ACC ] STREAM LISTENING 12728 /tmp/orbit-/linc-f84-0-14ef980cbbf24
unix 2 [ ACC ] STREAM LISTENING 12890 /tmp/orbit-/linc-fb7-0-70ad8fd6c0444
unix 2 [ ACC ] STREAM LISTENING 12949 /tmp/orbit-/linc-fbf-0-347a5a6e4992c
unix 2 [ ACC ] STREAM LISTENING 13768 /tmp/orbit-/linc-fc8-0-e27072a81a1a
unix 2 [ ACC ] STREAM LISTENING 13798 /tmp/orbit-/linc-1036-0-354f4bb9a7c4e
unix 2 [ ACC ] STREAM LISTENING 14163 /tmp/orbit-/linc-104d-0-465f514c7331c
unix 2 [ ACC ] STREAM LISTENING 14186 /tmp/orbit-/linc-1050-0-4db9ae50a624b
unix 2 [ ACC ] STREAM LISTENING 14207 /tmp/orbit-/linc-104a-0-36d44eeb8974
unix 2 [ ACC ] STREAM LISTENING 15070 /tmp/orbit-/linc-1092-0-66a1af2714f2f
unix 2 [ ACC ] STREAM LISTENING 19553 /tmp/orbit-/linc-1410-0-36f17e7c791ec
unix 2 [ ACC ] STREAM LISTENING 19158 /var/run/cups/cups.sock
unix 2 [ ACC ] STREAM LISTENING 16529 /tmp/orbit-linc-1193-0-1b2eb4df204f3
unix 2 [ ACC ] STREAM LISTENING 6332 @/var/run/hald/dbus-8dr65GBmM6
unix 2 [ ACC ] STREAM LISTENING 16612 /tmp/orbit-root/linc-119b-0-4753ff11c52d3
unix 2 [ ACC ] STREAM LISTENING 16631 /tmp/orbit-root/linc-1194-0-4b4cb3a1d035a
unix 2 [ ACC ] STREAM LISTENING 10573 @/tmp/dbus-FwQAqEcWx7

[__p1n__]

All those unix-domain sockets are internal ports that various services are listening on. Judging by the beau coup amount of gnome corba servers my guess is that you're running ubuntu and not kubuntu and also have a lot of things switched on.

[rookcifer]

Those are Unix Domain Sockets (http://en.wikipedia.org/wiki/Unix_domain_socket) and are *not* listening to the Internet at large. They are not TCP services.

If you just want to see what TCP ports are listening, you need to tweak that netstat command a bit. Try this:

sudo netstat -atpvnl

[sopadeajo]

Those are Unix Domain Sockets (http://en.wikipedia.org/wiki/Unix_domain_socket) and are *not* listening to the Internet at large. They are not TCP services.

If you just want to see what TCP ports are listening, you need to tweak that netstat command a bit. Try this:

sudo netstat -atpvnl

I get this: LISTEN 2983/cupsd which did not appear when using Netstat with the excellent GUI: Network Tools happily included with Ubuntu.
Hope this port is not kind of dangerous when listening.
Edited: it could be a program instead of a port, i do not know.
Edited2: ok, i can see now it is the internal number of the program that runs printers, not a port.

[cdenley]

I get this: LISTEN 2983/cupsd which did not appear when using Netstat with the excellent GUI: Network Tools happily included with Ubuntu.
Hope this port is not kind of dangerous when listening.
Edited: it could be a program instead of a port, i do not know.
Edited2: ok, i can see now it is the internal number of the program that runs printers, not a port.

The whole line should be

tcp 0 0 127.0.0.1:631 0.0.0.0:* LISTEN 4063/cupsd
The local address column has "127.0.0.1:631". This means it is listening on 127.0.0.1 port 631. It is a TCP port as the first column indicates. This should show up in the Network Tools GUI. That GUI does not display the process name and process ID, which is the part you posted.

[sopadeajo]

The whole line should be

tcp 0 0 127.0.0.1:631 0.0.0.0:* LISTEN 4063/cupsdThe local address column has "127.0.0.1:631". This means it is listening on 127.0.0.1 port 631. It is a TCP port as the first column indicates. This should show up in the Network Tools GUI. That GUI does not display the process name and process ID, which is the part you posted.
Ok,i get
tcp 0 0 127.0.0.1:631 0.0.0.0:* LISTEN 2990/cupsd The number 4063 or 2990 is a variable.


But i still would like to understand much more why are all these ports (though no TCP ports (are they UDP ports?)) are listening and to what are they listening.To processes, to programs??
What kind of hardware(or software ?) architecture is it? I am a newbie unsatisfied when not understanding.

[cdenley]

The number 4063 or 2990 is a variable.

But i still would like to understand much more why are all these ports (though no TCP ports (are they UDP ports?)) are listening and to what are they listening.To processes, to programs??
What kind of hardware(or software ?) architecture is it? I am a newbie unsatisfied when not understanding.

The number 4063 or 2990 is the PID (process ID) (http://en.wikipedia.org/wiki/Process_identifier) as the column header indicates. The protocol for most of the output in your first post is "unix". The column headers were printed, but didn't match your grep expression.
http://en.wikipedia.org/wiki/Unix_domain_socket
It is used for inter-process communication, not network communication. A process can listen for data from another process like with a network protocol, except it is more efficient and can only be accessed through the filesystem.