Stopping Server Processes

[TechGuy]

I am having a cable modem installed in the next few days and everything I have read says to stop all server processes to make it work. Especially sendmail. How do I do that?

[iDxMan]

Depending on what you need to stop, you'll probably have to change several things..

1) do: ps -ef|grep sendmail

ex output:

root 127 1 0 Jan01 ? 00:00:00 sendmail: accepting connections


now : kill 127

You should go edit your startup files to ensure sendmail doesn't re-start next time you boot. Depending on what distro you use, these files may vary..

2) edit /etc/inetd.conf

put a hash (#) in front of services that you don't need up. eg: telnet,ftp,rlogin,etc..

save,exit.
type: killall -HUP inetd

3) type: netstat -an|less

ex output:

Active Internet connections (servers and established)
Proto Recv-Q Send-Q Local Address Foreign Address State
tcp 0 4 192.168.X.X:23 192.168.X.X:1449 ESTABLISHED
tcp 0 0 0.0.0.0:80 0.0.0.0:* LISTEN
tcp 0 0 0.0.0.0:587 0.0.0.0:* LISTEN
tcp 0 0 0.0.0.0:25 0.0.0.0:* LISTEN
tcp 0 0 0.0.0.0:515 0.0.0.0:* LISTEN
tcp 0 0 0.0.0.0:23 0.0.0.0:* LISTEN
tcp 0 0 0.0.0.0:21 0.0.0.0:* LISTEN
udp 0 0 192.168.X.X:123 0.0.0.0:*
udp 0 0 127.0.0.1:123 0.0.0.0:*
udp 0 0 0.0.0.0:123 0.0.0.0:*
udp 0 0 0.0.0.0:67 0.0.0.0:*
raw 0 0 0.0.0.0:1 0.0.0.0:* 7
raw 0 0 0.0.0.0:1 0.0.0.0:* 7
raw 0 0 0.0.0.0:6 0.0.0.0:* 7


Look to see what ports the system is listening to. Perhaps you will need to kill other services such as portmap (111) or samba (137-139).. Poke around and see what you can find..

BTW, you don't have to stop processes to make it work. This is only to make sure you don't have an open door to attackers.


-r

[This message has been edited by iDxMan (edited 09 January 2001).]

[TechGuy]

So if I set up a server with the cable modem attached to it and my workstations off the server with the firewall running then it should not matter?

[iDxMan]

In theory yes, you should be fine unless something goes weird with the firewall.

I have several services up (such as apache/ftp/telnet/samba/etc.) that are used for the internal network ONLY. All traffic on those ports from the internet is blocked, so I should be fine..

-r

[Bully]

Hellooooo,
Isn't it better to use the shutdown scripts to stop processes?
ie. $/etc/rc.d/init.d/sendmail stop
I've always liked this way rather than "kill"ing them... I don't know why but it always seemed like a nasty command that ;OP

You may find that if you're using xinetd that the seperate services can be disabled individually from it's config file in /etc/xinet.d/

Say if you wanted to disable imap, open up the file "imap" in this dir and make sure there is a "yes" next to disable. :O)

Cool!

Bully

[iDxMan]

Originally posted by Bully:
Hellooooo,
Isn't it better to use the shutdown scripts to stop processes?
ie. $/etc/rc.d/init.d/sendmail stop
I've always liked this way rather than "kill"ing them... I don't know why but it always seemed like a nasty command that ;OP


Hiiiiii,

Not every distro uses sysV init scripts. I was trying to keep my explanation as generic and/or non distro-specific as I could. FYI: I use slackware, so if I told him to go edit /etc/rc.d/rc.M and hash out the sendmail area near line 115 it might not work very well when, for example, he's using Redhat.

There's nothing wrong with kill. The scripts could do more cleanup, startup/shutdown error checking, but using kill is the quickest way to shutdown a process no matter what distro you're on.

-r

[This message has been edited by iDxMan (edited 10 January 2001).]

[Bully]

Yeah matey, I'm RH mook and haven't tried any other distro's yet. :O)

Thanks for the info tho!

Cheers,
Bully