- Everything was working fine with server2 until I had to reboot.
- Since reboot, I cannot SSH into the machine directly, and, http is not working...MOST of the time.
- Every once in a while, randomly, I can suddenly get in. But most of the time, the connections time out.
- I CAN SSH from server1 into server2. This always works, but access from the outside is sporadic at best.
- Firewall is not blocking those ports and the ports always reply
- WGET from server2 is timing out as well. Even when SSH and HTTP happens to work that particular minute, WGET never works.
The first few things I would check for are the following:
- Does server2 have the correct network prefix and gateway address configured on the network interface?
arp -non server2 show an entry for the gateway?
- If possible, check
arp -non the gateway as well looking for an entry for server2.
Sporadic connectivity like you describe can happen in scenarios where arp request and replies between gateway and host is for some reason not working, but they can pick up each other's MAC address anyway by watching arp requests. In one such case I was able to temporarily work around the problem by pinging an unused IP address on the LAN from the problematic host, until I found the root case, which was conflicting RFC1918 addresses assigned on two different interfaces.