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I just ran nmap on a Fedora system and the only interesting item was:
PORT STATE SERVICE
2000/tcp open callbook
I have been looking everywhere and I only see reference to this "callbook" in other postings of open ports. However I am trying to find out exactly what this service is.
Any pointers in the right direction would be appreciated.
ps -aux show every running process
netstat -nat shows all open ports
nmap -sV checks service & app names/versions
and chkrootkit checks for rootkits on your system.
Thanks for the help, I have found it to be Asterisk. nMap says it is unknown what it is. I turned off the asterisk service though and ran nmap again and port 2000 was not showing up. So now I know what is going on.
BTW Is there a command that will tell you which process is using which port?
Is there a command that will tell you which process is using which port?
Given a Proccess Id try 'lsof -Pwnp [PID] -ai'. Without Process Id try 'lsof -Pwnai' or 'netstat -antupe'.
Given a port number try '/sbin/fuser -n [PROTOCOL] [PORT_NUMBER]'.
Given a service name (/etc/services) try '/sbin/fuser -n [PROTOCOL] [SERVICE_NAME]'.
* Note you can keep tools from resolving address, service and port names to speed up execution often using switches like "-n".
** Also see 'iptstate -fs -D [REMOTE_IP]', 'awk '/dport=[PORT_NUMBER]/ {print}' /proc/net/ip_conntrack;'.
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