Odd router problem

[JareBaav]

My basic setup...

Router: BT Voyager 2100 wireless (combining ADSL modem}.
PC1: BT Voyager 1040 PCI wireless adapter, and onboard LAN (connected directly to router).
PC2: BT Voyager 1040 PCI wireless adapter.

The router setup has been configured not to designate either PC as a DMZ host...

Those IP packets from the Internet that do NOT belong to any applications configured in the port forwarding table will be: Discarded

I can\'t remember the exact chronology of events, but when I first installed Planeshift (May/June 2005), I could play without having to forward any ports. I can still play now without needing to forward ports but, somewhere along the line, I spotted several posts in these forums about forwarding ports 13331 UDP and 7354 UDP. I forwarded these ports thinking it may help prevent some of the random PS crashes I was experiencing, but it didn\'t. In fact it introduced a whole new problem.

Intermittently (more often than not), when I logout of PS or when psclient or the server crashes, I find I either have limited or no access to the internet at all.

By limited access I mean...

I can browse some websites and not others.
My email client will  connect to some mail servers and not others when trying to retrieve mail.
My news client may or may not be able to connect to the various news servers I subscribe to.

The next thing leads to a clue I think... I can not access the router\'s configuration pages by the normal means of typing http://voyager.home into my web browser. I have to use the router\'s IP address 192.168.1.1. This leads me to believe that a DNS problem has occurred somewhere.

To resume a normal service, I have to reboot the router, either by the configuration pages or by pressing the router\'s reset button (not factory reset). Rebooting the PC has no effect.

None of the above happens if I don\'t forward ports 13331 and 7354.

I don\'t think there\'s a problem with the router itself as, for example, I need to forward ports for the p2p client that I use for file sharing to work properly, and I must forward ports for other software to communicate properly with the internet.

Should I need to forward ports 13331 and 7354 and why do I get this problem if I do?

Thanks for any advice.

P.S. I use NIS 2005. Disabling it doesn\'t help when the problem occurs, but I haven\'t tried disabling it before a game session.

[steuben]

given that resetting the router lines things up a again, that leads me to suspect the router. next time try rebooting the comp, see if that fixes things. alternately if you\'re using xp try \"repairing\" the connection.

that and are both pcs affected at the same time?

[JareBaav]

Originally posted by steuben
given that resetting the router lines things up a again, that leads me to suspect the router..

Yes, I also suspect the problem is routerside, but why? Especially as the problem only happens if I forward those two ports. Forwarding any other ports for other applications has never caused a problem.

Originally posted by steuben
next time try rebooting the comp, see if that fixes things.

Originally posted by JareBaav
Rebooting the PC has no effect.

Originally posted by steuben
alternately if you\'re using xp try \"repairing\" the connection.

that and are both pcs affected at the same time?

Next occurrence I will try the repair connection option and check if the same problem is evident on PC2.

Thanks.

[The Doctor]

Try lowering the MTU on either your router, or your PC if you cannot set it at the router.  I have seen a lot of routers with a MTU of 1500 essentially flood themselves off.  Setting the MTU to 1492 might solve the problem.

[JareBaav]

Originally posted by The Doctor
Try lowering the MTU on either your router, or your PC if you cannot set it at the router.  I have seen a lot of routers with a MTU of 1500 essentially flood themselves off.  Setting the MTU to 1492 might solve the problem.

Well I\'ve set the MTU down from the pre set 1500, but no one\'s said whether I actually need to forward these ports, seeing as PS plays reasonably well for me without doing so.

[steuben]

baseline...
it should still work with the ports forwarded. but if it works without forwarding, and does odd things with forwarding. then the simple step here is to not forward.

[Seytra]

You don\'t need to forward the ports. This is necessary only if your router / firewall is stateless and thus cannot track UDP traffic. This may, BTW, be the difference here, too:
While PS uses UDP, most other apps, like P2P clients, use TCP. Therefore, your router may have a bug in the UDP port forwarding part, and thus it will show only if youi use that, i.e., when you run PS.

Most recent routers will be stateful and thus not require port forwarding for PS. I\'m running PS from behind a router and port forwarding is not required. The crashes are bugs in PS, most commonly sound problems or (I guess) invalid / unparsed messages. Turning off sound might help you with that, though the big update has brought with it the expected amount of spurious non-sound crashes, too.

Edit: BTW, port 13331 is not recent information. It was used for the old (MB) client, but now the (CB) client uses a different port, port 7354.

Also, you might be able to get a fresh firmware for your router that corrects the bug. Maybe it will add others, though, so update only if you really need to, which AFAICS you don\'t. You might however want to download it (if it exists) anyway, just in case the company decides to drop support for the router or goes out of business and you need it in the future.

Edit2: The UDP bug is likely, in fact, because DNS uses UDP for short queries. Therefore, once UDP is confused, new DNS queries won\'t get through unless they use TCP. What makes some things work may be that or that the DNS resolving information is cached locally and thus no DNS query is sent at all.

[JareBaav]

@Seytra

The p2p client in question requires both a TCP and UDP port to be forwarded, the UDP for full search capabilities.

As it happens, there is recent firmware upgrade available. I have avoided their previous offering as it screwed up the the functionality of the router\'s configuration pages (I did try it once, but luckily the supplier agreed to replace the router under warranty. In fact the supplier was so obliging that they booted up several routers for me until they found one that didn\'t have that particular firmware version pre-installed).

@ The Doctor

The new firmware is pre-configured with the MTU set at 1400. I\'ll leave it at that for now, but would you suggest upping it to 1492?

Anyhow, I\'ll forward just port 7354 UDP now and see how that pans out.

Thanks for everyone\'s input.