Overview

When a Pod becomes unreachable, it is usually one of four things: the interface is down, the OS firewall is blocking traffic, the ALYPOD cloud firewall is blocking traffic, or the service itself is not listening. This article walks through a systematic check.

Before you begin

• Console access to your Pod (the browser console lets you get in even when SSH fails).
• The public IP address of the Pod.

Steps

Work from the server outward.

1. Can you reach the console? If the browser console works but SSH does not, the network is up and the problem is the SSH service or a firewall rule.

2. Check the interface and address inside the Pod:

bash ip -brief addr ip route ping -c 3 1.1.1.1

If ping fails, the Pod is not routing. Verify the IP and gateway in the Console.

1. Check DNS resolution:

bash dig +short alypod.com ping -c 3 alypod.com

If DNS fails, edit /etc/resolv.conf or your NetworkManager connection and use a resolver such as 1.1.1.1 or 8.8.8.8.

1. Check listening services:

bash sudo ss -tlnp

Make sure the service is listening on the expected port and on 0.0.0.0/:: rather than 127.0.0.1 only.

1. Check the OS firewall:

bash sudo ufw status verbose # Debian/Ubuntu sudo firewall-cmd --list-all # Rocky/AlmaLinux

1. Check the ALYPOD cloud firewall in the Console under Networking. Confirm the relevant port is allowed from your source address.

2. Test from outside using ping, traceroute or tcping from your workstation.

Common culprits

• SSH was moved to a new port but the firewall still allows only 22.
• A service binds to localhost only.
• Rules were added at runtime in firewalld but not made permanent.
• The Pod's public IP changed after a rebuild.

Escalation

If everything above is correct and traffic still does not arrive, open a ticket from account.alypod.com with the Pod name, timestamps and the output of your tests.

Related articles

• [Testing connectivity with ping, traceroute and mtr]
• [Configuring a firewall with ufw]