TCP Listening Ports

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# 1  
Old 05-23-2002
TCP Listening Ports

Hello all,

Can someone instruct me on how to change the listening port for ftp ( or any tcp service) from 21 to another port number? Thanks in advance..

# 2  
Old 05-23-2002
Do you have a /etc/services file?.

Regards. Hugo.
# 3  
Old 05-23-2002
Yes, i do...Am I suppose to change port number from this file?

# 4  
Old 05-24-2002
Under most circumstances, I would not recomend changing anything in the /etc/services file.
You can if you want utilities like netstat to show the names, as opposed to the numbers of ports in use / listening, etc...

Find out where you ftp daemon is being started (statup script, inetd, somewhere else?). You should be able to change a command-line option there to change the default port.
Look at your ftpd man page for more info.

For example, on one of my systems, the man page tells me that I can specify the control and data ports with -p and -P

So if I changed a line in /etc/inetd.conf to:
ftpd -p 3040 -P 3039
It would run ftpd with a control port of 3040, and data port of 3039.
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