How to check if a port is opened or closed on a VPS linux?

[melviin]

I am running a VPS for testing my blogs. I want to know how to check if a port is opened or closed on a VPS linux?

If it's opening then how to close it and vise versa?

 

[Hassan]

nmap -sT -O localhost

Use iptables for close ports.

 

[ElixantTechnology]

Does your VPS have cPanel or DirectAdmin on it? If so, I recommend installing ConfigServer Firewall; this will give you a nice interface to manage your firewall and some security tips/pointers

 

[RDO Servers]

There are also several online port scanners you can use.

After checking everything server side, I like using these as a double check to see what is globally open.