Mogodb secondary node port not coming up

Hi

We have our mongo in a on prem. primary node we are able to connect . secondary node port is not up.
If i check rs.status() from primary ,secondary node is in not reachable state.
Tried restarting also .
I am not sure what to do to resolve this.
Any suggestion

How many nodes in your replica setup?
When you restarted secondary node did it come up successfully?
Check your mongod.log

Verify that the MongoDB port (default is 27017) is open and accessible for your secondary node and check if any firewall settings are blocking access to port. check your mongod.conf file and compare replicaset, bindip and port details with primary, Try restarting mongod on secondary node and check connectivity between primary and secondary using telnet or ping. review mongod.log and search for errors.