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What is a TCP Check?

Solution ID : SO273
Last Modified : 10/21/2023

Common questions:

  • Does my domain resolve over this port?
  • How do I check connectivity over a specific port?

How TCP checks work:

Attempts to open a TCP connection on the specified port. 

You can test if the port is available over TCP by running telnet in the terminal by typing telnet followed by the IP and then the port number:

# telnet <IP address> <port number>

# telnet 23

If you are able to connect and it does not timeout, then our monitoring systems will pass it in a TCP check.