Getting the MTU error when MTU is fine.....

Ok, first off, im not some dumb 12 year old whos going to ask a bunch of stupid questions. I am an IT Tech so for the most part I know what I'm doing.

I keep getting the mtu error, but I've checked my mtu's between the xbox and the internet and they all read back 1400+, well above the minimal limit to get on xbl.

All the ports are open, I can see the mtu test going in a packet scan, but it never works out.

I've done all the simple stuff like reboot everything but that didnt seem to help at all.

 

Question Info


Last updated July 4, 2018 Views 15 Applies to:

What Country/State/Province do you live in? USA - Florida

Modem brand & model number: Motorola Surfboard SB5101

Router brand & model number: Belkin F5D8233

Network Connection Type: Wireless/Wired Both, depends if I want to have a cable running down the hallway or not

If Wireless, what type of encryption are you using? WPA AES

Things you have tried: Manually set MTU on the server that handles NAT. Double checked Firewall settings on the server, removed the firewall, the only way my xbox will work is plugged in directly to the modem, this IS NOT A SOLUTION FOR ME. This worked fine until I plugged the wire in, then it all stopped working. I can no longer go back to wireless and have it work.

Is UPnP Enabled? No.

Is NAT Type Open? Moderate, never could get it to say open

Any Error Codes you encounter: The one about the MTU, thats it. No errors on the server.

What type of internet do you have? Cable

Who is your ISP(Internet Service Provider)? Comcast

When you run "Test Xbox LIVE connection" what is the exact message shown on screen? Your network does not have a sufficient MTU setting. Xbox LIVE requires a minimum MTU setting of 1364.

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IFCONFIG OUTPUT:

me@box:$ ifconfig

eth0      Link encap:Ethernet  HWaddr 00:e0:29:50:18:cd

         inet addr:192.168.0.1  Bcast:192.168.1.255  Mask:255.255.255.0

         inet6 addr: fe80::2e0:29ff:fe50:18cd/64 Scope:Link

         UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1

         RX packets:71316136 errors:0 dropped:0 overruns:0 frame:0

         TX packets:75410148 errors:0 dropped:0 overruns:5 carrier:0

         collisions:0 txqueuelen:1000

         RX bytes:975829338 (930.6 MB)  TX bytes:2800745833 (2.6 GB)

         Interrupt:17 Base address:0xb000

eth1      Link encap:Ethernet  HWaddr 00:18:f8:0b:f2:4e

         inet addr:[removed]  Bcast:255.255.255.255  Mask:255.255.254.0

         inet6 addr: fe80::218:f8ff:fe0b:f24e/64 Scope:Link

         UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1

         RX packets:49123200 errors:0 dropped:0 overruns:0 frame:0

         TX packets:18505431 errors:8 dropped:0 overruns:0 carrier:8

         collisions:0 txqueuelen:1000

         RX bytes:87435339 (83.3 MB)  TX bytes:2358081000 (2.1 GB)

         Interrupt:16 Base address:0xb400

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Hi,

 

This is quite common with Belkin N's its not a real MTU error, make sure you are using the latest version of firmware on the router and just UPnP only and the Xbox ip address set to auto (no port forwarding). If that doesn't resolve it, this will:- www.unofficialguidetolive.co.uk/.../62-my-nat-is-strict-or-moderate

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LOL, somehow I just knew it was going to be you showing up here first. I did take the time to lurk the forums here and other places before posting. Unfortunately this was not the answer, the router that I do have in use does not come into play on the wire, things go like this [modem] - [server] - [hub] - [LAN and Wifi access point here]

Turns out I had a nic failing in the server which was not affecting my MTU, but it was mucking up a few packets in transit. I figured it out after a few tcpdumps on the xbox. Some of the packet data was incomplete and a few times wireshark didnt even want to open the dumps because of some cluster-f***.... I mean cluster fail in the data.

Swapped out the nic and im back to my pleasant moderate nat. Seeing as the only people I should have trouble with joining and talking to are strict nat ppl, I will be more than happy to help them get to moderate nat if I really want to play games with them that bad.

Thank you for your time none the less. Feel free to add my gamer tag in case you need a really good geek for some input on these forums here. I'm going to get back to shooting people in the face. Always a good way to end a LONG night of debugging. xD

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Turned out to be a bad Network Interface Card (Eathernet Card) in my server which acts as the main router for my network.

(I just put this here so people browsing these forums later can find a short answer)

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lol, ok glad your all sorted

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