The situation: I have one machine connected to the inet acting as a firewall/webserver/email server/ssh server and one machine inside that firewall. Since I don't have access to another machine outside my firewall that I can install nmap on I installed it on the machine behind the firewall and the server itself. Now I have run a port scan on the server from the comp inside the firewall and i get the following:
Port State Service
22/tcp open ssh
25/tcp open smtp
53/tcp open domain
80/tcp open http
111/tcp open sunrpc
443/tcp open https

I expect ssh, smtp, and http. I am not sure I should expect https(I don't have any secure content on the webserver) or domain(used for dhcp?) and I have no clue what sunrpc is for. I have tried checking and making sure that I don't have these services running (using service -s) and I don't see any mention of sunrpc except in the iptables output. Basically I just want to know what I should close down to make my machine more sercure.
Thanks for any help!

Well the sunrpc can be turned of by renaming or removing a line in /etc/rc.d init scripts.

in redhat and mandy type ntsysv and turn off portmap, or rename /etc/rc.d/rc?.d/S??portmap to K??portmap where rc?.d is the runlevel that the server is running at, and S??portmap your may be different, mine was S87portmap, I renamed it to K87portmap.

in slackware look at /etc/rc.d/rc.inet2 there will be some lines like this:
if [ -x /sbin/rpc.portmap ] ; then
echo "Starting RPC portmap: /sbin/rpc.portmap"
/sbin/rpc.portmap
fi
comment the lines out
so it would look like this when you are done:
#if [ -x /sbin/rpc.portmap ] ; then
#echo "Starting RPC portmap: /sbin/rpc.portmap"
#/sbin/rpc.portmap
#fi