topic Re: Unix Socket Domains ? in Operating System - Linux

Unix Socket Domains ?

Maaz — Mon, 11 Apr 2005 13:29:45 GMT

Hello Dear Experts

# netstat -l
shows Unix Domain Socket.
May I ask what is Unix Domain Socket ?

Regards
Maaz

Re: Unix Socket Domains ?

Steven E. Protter — Mon, 11 Apr 2005 13:31:51 GMT

Unix socket is a port 53 domain name DNS lookup.

SEP

Re: Unix Socket Domains ?

Maaz — Mon, 11 Apr 2005 14:07:57 GMT

Dear SEP, if u can plz elaborate ...

which client does this(Unix domain socket) lookup ? and why ?

I ran netstat and it shows me Unix domain sockets as well, although my machine is neither a DNS server, nor client

Regards
Maaz

Re: Unix Socket Domains ?

Uwe Zessin — Mon, 11 Apr 2005 14:09:34 GMT

Rather looks like an interprocess communications vehicle to me:
http://publib.boulder.ibm.com/infocenter/pseries/index.jsp?topic=/com.ibm.aix.doc/aixprggd/progcomc/skt_comms.htm

Look for "UNIX Domain Properties".

Re: Unix Socket Domains ?

Dave Falloon — Mon, 11 Apr 2005 14:27:04 GMT

Unix Sockets are internal communications points, they behave the same way network sockets do only they apply to the loopback adapter.

Many application suites use multiple daemons, these daemons can exist on different machines or on the same machine. For instance samba and winbind, the smbd deamon will use a unix domain socket to communicate with winbind. Mysql uses a named pipe if I'm not mistaken to communicate internally. You will see a file named mysql.sock which is essentially the same as the tcp socket socket when you get down to brass tacks. The only difference is the named pipe shows up in an ls.

Typically you want to worry about the external sockets, so you filter the netstat results to omit unix sockets if you have a lot of connections. I use these switches:

netstat -pantu inet

Gives me lots of info excluding all the socket connections for internal process communication.

--Dave

Re: Unix Socket Domains ?

Maaz — Tue, 12 Apr 2005 01:06:59 GMT

Many Thanks Dear Uwe Zessin.

Dear Dave Falloon, I m highly thankful to u for such a nice explanation... again Millions of Thanks

Regards
Maaz

Re: Unix Socket Domains ?

Huc_1 — Tue, 12 Apr 2005 07:40:04 GMT

On my system only the syntax is
#netstat -pantu
or
#netstat -pantu --inet

But I usualy use the lsof

like ex:

#lsof -i

this will show all open net connection have a look at man lsof if this tool is on your system this tool can do a lot for you.

J-P Huc

Re: Unix Socket Domains ?

Maaz — Tue, 12 Apr 2005 13:44:13 GMT

Nice help Dear J-P Huc.
And thanks for continous support

Regards
Maaz