closing open ports

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# 8  
Old 09-27-2001
One last thing----

Just one last little bit, your inetd.conf file is a better reference for what is running on the box, under inetd,(not to mention the use of lsof and looking at /etc/services) than an nmap scan. nmap is guessing at what is running on what port from a list of what is assumed to be a known service on those ports, usually anything above port 1024 (and sometimes, below it) is arbitrarily set to serve from that port. BackOrifice and NetBus could be config'd to run from other ports, so can netcat and other such tools. Your best bet is stripping down to only what you need, and keeping a sharp eye out for any new servers being put out there. You can use lsof to get an idea (okay, see what's happening) of exactly what proc is using which port so you can see who is serving what out of your box.
The nmap scans are excellent for finding servers that are nto running under inetd's auspices. Sounds like you're going in the right direction....


# 9  
Old 09-27-2001

I've never seen SIGUSR1 used for this.
It has always been SIGHUP.

The way to get inetd to re-read inetd.conf

find the process id of inetd...

ps -ef | grep inetd

...then as root do...

kill -HUP process_id_of_inetd

... it apparently ignores the signal if it did
not come from root.

Are you sure Linux uses SIGUSR1?
# 10  
Old 09-27-2001

Absolutely Beautiful...

kill -HUP pid

worked like a charm...

new nmap scan of the external interface reports that ftp and telnet are toast..

thanks for the help...

# 11  
Old 09-28-2001
For clarity sake, the SIGUSR1 kill spec is used for xinetd. Regular ol' inted, HUP (signal 1) should work.

Also, for lazy people like me, I usually just do this:
killall -1 inetd

It kills by name rather than trying to find the PID.
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