Strange port usage

[Jim]

  i'm using linux 2.4.22
> there's strange behaviour in my box
> sometimes when i run netstat -atu
> i get udp 0 0 *:878 *:*
> an another time *:876 or *:875
> i run rpcinfo but none of those ports are listed.
> i run nmap -sU and i get this result " 878/udp open unknown "
> how to find out what program/service is using this port?
> is this trojan?
> 

you can use lsof or fuser:
fuser -n udp 878 # returns PID of the proc using that port
lsof -i udp:878 

i like to run this command to see what deamon programs are listening and on
what port:
lsof | grep -i listen

---
Outgoing mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.772 / Virus Database: 519 - Release Date: 10/1/2004