Lab:34 N W Troubleshooting ‐ Two Server in the same subnet,There is issue to reach port on one of the server(Hint ‐ firewall‐cmd) - TanveeKhanDB/OCI GitHub Wiki

N/W Troubleshooting - Two Server in the same subnet

Problem statment:

There are two server Source_server & Destination_server in same subnet using the same SL now we want to perform telnet from Source_server to Destiantion_Server via their private ip.

Instance details:

Step by step process to resolve this issue

1.login via putty to the Source _Server from our machine.

  1. Verify basic connectivity of these two server via PING Command

ping <Destination_Server_Private_IP>

3.Checking port connectivity from Source_Server to Destiantion_Server

telnet <Destiantion_Server_Private_IP> <Port_Number>

Unable to connect

4.Will check firewall at server level.

systemctl status firewalld

  1. Will check the eligible port list at server side.

firewall-cmd --list-ports

Note: This command should run on root level

No such port is availble hence will add our req port at firewall list.

6.Adding port 80

firewall-cmd --permanent --zone=public --add-port=80/tcp

Its added successfully.

  1. Now will reload cross check the port list:

firewall-cmd --reload

firewall-cmd --list-ports

8.Perform telnet again to validate port 80 reachabilty to server.

telnet<Destination_Server_Private_IP>