1.7.10 Forge 1291 Inconsistent Network Issues

[Demosthenexx]

I have two new server instances setup with a custom modpack, Minecraft 1.7.10, and Forge 1291. The servers are test and production for the same code, all mods and config files are identical and copied out of my Git repo. They run on different ports with more memory to prod. Both servers save to SSD. Host is Linux, no firewall locally. LAN connections have the same issues as remote NAT connections, so Internet facing firewall isn't the issue.

 

No problems in test. No errors on launch, server is visible in server list and clients connect normally. 10 players max online during test, no network issues.

 

Prod instance on the same server (separate port) *always* shows as down in the server list (red X) on first open, even when it's up. You can hit refresh, normally it doesn't change the state. If you try to connect anyway you can get in after several attempts. Half the time it must timeout once first (if you cancel, it still won't work until you timeout). I have 15+ players online and no lag, but frequent odd network issues like this.

 

The logs below are too big for pastebin, the client has TRACE enabled. This was recorded during a client trying to connect and timing out.

 

http://demosthenes.org/tmp/client.log

http://demosthenes.org/tmp/server.log

 

Other than these logs I'm not sure where to start troubleshooting. I've not yet seen any one mod fingered in the logs, there's no crashes. Just failure to connect to one server when it's the duplicate of another.

 

[LexManos]

Sounds like your second server is having internet issues. Possibly router or firewall issues. Nothing to do with Forge itself.

Also your logs are useless the server just shows a disconnect and the client shows nothing.

[Demosthenexx]

Sounds like your second server is having internet issues. Possibly router or firewall issues. Nothing to do with Forge itself.

Also your logs are useless the server just shows a disconnect and the client shows nothing.

 

Again it's the second server instance on the same host. LAN players have the same issue, it isn't the Internet facing side. LAN players are inside the firewall, there is not a local one.

 

I thought the logs were light, I didn't see anything.

 

My only thought next is a packet trace to compare one to the other.

[Demosthenexx]

Packet trace clearly shows a long conversation with the test instance which dumps the modlist as json and other server stats. The prod instance never replies, but sends a few packets to close the connection.

 

I understand the log files weren't useful, so what additional logging could I add?