Linux Port related Operations

Redhat Query Port Usage command:

grep < port number or program name >

Natstat Related parameters

-A (All) displays all options and does not show listen related by default
-T (TCP) displays only TCP-related options
-U (UDP) displays only UDP-related options
-N refuses to display aliases, showing all numbers converted to numbers.
-l list only service status in Listen (listening)

-P Displays the program name that establishes the associated link
-R display routing information, routing table
-e display extended information, such as UID, etc.
-S statistics according to each protocol
-C executes the netstat command every other fixed time.

Hint: The status of listen and listening can only be seen with-a or-l

Open a port

8771 -j ACCEPT

Linux Port related Operations