nmap (aka network mapper) is used to identify what ports are open for a given vm.
Announcement
I have released my new course on Udemy, Kubernetes By Example. Sign up now to get free lifetime access!$ yum install nmap
then simply run:
$ nmap {ip-address}
or
$ nmap example.com
You can also scan a range of ip addresses:
$ nmap 192.168.1.1-100
nmap is useful if you want to quickly list out all open ports for localhost:
$ nmap localhost