I was thrilled to change from my previous provider to T-Mobile's internet. The speed is great. The service has been super reliable. Where I'm having trouble is on my Nintendo Switch. I can't get visitors on my island on Animal Crossing. I can't race against friends on Mario Kart. Virtually all online gaming functionality is useless. And I'm frustrated I haven't been able to find a solution. I called support and they basically said there's nothing they can do. Has anyone found any solution to this?!

It basically boils down to an infrastructure problem TMO needs to fix on the other side of the modem first, and then updating the modem's firmware to properly enable/allow port forwarding to work.EDIT: forgive me for the length of this post... it is a bit of a sore spot in the community, for obvious reasons like what you are experiencing. The TLDR--gaming and IoT devices were NOT considered when they cobbled this service together. It is really only designed for some of the most casual of users out there. Unfortunately, the marketing and even their own reps do not make this distinction up front. You MIGHT be able to get around some issues IF you can use a VPN with what you are doing... but success is limited due to issues with how things are managed. Their network is IPv6 only. Way too many devices and applications are designed with IPv4 with port assignments in mind. While you can still assign ports with v6 addresses, the bigger problem is the reliance on v4 addressing. You can't just "send" v4 addresses over v6 networks--the packets have to be altered on both ends of the v6 network for that network to carry the data back and forth to another v4 client (ie: some games trying to communicate with it's server via UDP protocol and v4 addressing).TMO opted for an implementation of XLAT464 to handle the dual stack scenario that does not work for the peer-to-peer communication that many of these devices/applications depend on to function properly. While it works to get mostly all "stateful" v4 communications back and forth (you request outbound TCPIP connections that are established/tracked so they can transmit back to you), the "stateless" ones are broken. These are the types of connections that are not tracked at all... often UDP and not TCPIP, or otherwise inbound and unsolicited (you did not open a connection to them first--they are trying to reach out to you directly). These typically need a routing rule to forward such inbound traffic to a specific device, be that filtering by specific ports (set manually or via UPnP feature) or a DMZ rule that forwards all untracked/unassigned traffic to a particular device.In theory, we should be able to get away with a DMZ rule on their modem to get around it--but their 464 implementation breaks things because of how they are filtering/shaping traffic. It is behaving more like a "public" free VPN, or Carrier Grade NAT. These can cause the public IP address to actually be used for multiple private users, so there is no 1 to 1 public address that can be paired to your modem or router's private IP in the usual fashion that would allow those peer communications to work properly. Communications MUST be initiated from your end first, and then the other end has to follow specific rules to reach back to you through that same connection for it to make sure it gets back to you properly.Some have managed to get around it somewhat with a paid VPN service... but to get it work for things like game consoles it will require a VPN to run on your own router, which may narrow (or even void) your options considerably depending on specifics of your router.And then there is the issue of the extra encapsulation for their 464 translation layer. They have to use more space in the packet headers for their encapsulation, which reduces how much user data can go in each packet. Instead of the more common 1500 byte client side MTU that leaves a 1460 byte MSS for user data, things get reduced to a 1420 MTU for the client, leaving only 1380 bytes for user data. Some VPN's reduce this down to 1320 or less by default to avoid potential issues with their encapsulation--but not all of them. So some are having issues getting VPN's to work properly... and not all allow the user to override the MTU or MSS values to fix it.Basically... a LOT of people are getting hosed because TMO didn't have a clue of how people more often use their internet these days. They are set up more for the extremely casual user... at best, a Netflix streamer and social media user. Avid gamers certainly were NOT a consideration for this product... Heck, even the more casual gamer that likes the odd FPS game can get screwed by this system./endrant

I can't play my Nintendo switch online it says"Error Code: 2618-0521The server is operating normally.The NAT traversal process may have failed.Please try again later.If the problem persists, your network conditions may not be suited to stableonline play.(50006)" my connection test says my Nat Type is D. I don't know why all the sudden it's stop connecting online I've been playing online fine for 3wks. Hopefully this get fixed I paid for a year of Nintendo online play so if it not fixed I have to get another home Internet

In other words, someone at T-Mobile needs to read this and fix it stat! LOL. Darn. That sucks. Well, looks like I'll be going back to my previous provider for now. It is what it is.

So is that just it? If you have T-Mobile 5G internet. You can't play most games online with Nintendo switch?

I have to use my iPhone 12 hot spot to play switch online. Please explain this to me? T-mobile needs to get their engineers working with Nokia to engage these most basic of hardware features that are needed.

Nintendo Switch w/NOK 5G21 Gateway | Comunidad de T-Mobile

TheBoller
Newbie Caller
Hace 3 años
I also have a fix. Go to your local T-Mobile store and ask for the new KVD21 home internet gateway. I swapped my out today with the new KVD21 and we can play Splatoon and Rocket League again!!!!
And this one gets a better signal (4 bars instead of 3) in the exact same spot as our old one.
villageheresy
Network Novice
Hace 3 años
PAY ATTENTION PEOPLE, I HAVE SOLVED THE ISSUE---at a price of 30$

When I first got my TMOBILE tower, MarioKart online worked fine...then it didn’t.
Two months of trying everything left me with a NAT type D and an inability to connect.

SOLUTION THAT WORKED:

Ordered from Amazon, an official Nintendo “Wired Internet LAN adapter”

The weak spot on the Switch seems to be that it is wireless without an ethernet plug in. This adapter allows ethernet to be plugged in through the USB.

Instantly up to NAT type B and racing my heart out.

Did not even have to institute plan B which was to use this product AND kick everybody else off of the connection.

Still pissed at T-Mobile for making me sinking hours into solving an issue that should have never existed, but glad to be on the other side of this.

This solution is perfect for those that are not tech savy and are intimidated by the talk of VPNs.
KWaters
Roaming Rookie
Hace 3 años
D-ocons wrote:

So is that just it?

If you have T-Mobile 5G internet. You can't play most games online with Nintendo switch?

@t-mobile this is a HUGE PROBLEM and you need to be upfront about it when your selling this crap
KWaters
Roaming Rookie
Hace 3 años
tenthredemption wrote:

I was thrilled to change from my previous provider to T-Mobile's internet. The speed is great. The service has been super reliable. Where I'm having trouble is on my Nintendo Switch. I can't get visitors on my island on Animal Crossing. I can't race against friends on Mario Kart. Virtually all online gaming functionality is useless. And I'm frustrated I haven't been able to find a solution. I called support and they basically said there's nothing they can do. Has anyone found any solution to this?!

This I just recently got T-Mobile and it's still very much a problem. What's the point of having switch online if I can't use it?? I even tried using my phone as a hotspot like some people had to do but because my phone providers also T-Mobile it doesn't work.
FtotheG
Network Novice
Hace 3 años
I just got the Nokia modem/router over a week ago. I had the same issue with Mario kart. Then a few days ago, my modem received some OTA firmware update that fixed the issue. When it check the NAT on the Switch it is on B instead of D. I have been able to successfully join online races for the past few days without any issues. For me, at least, it looks like everything is working as a home internet connection is expected to work. I think I will be keeping this and saving $70 bucks over my cable internet. sorry, Comcast.
thatzrazin
Newbie Caller
Hace 3 años
TuesdayB wrote:

Guys following this changed my NAT type from D to B on the switch. Haven't tested with game yet but let me know if this works out for you guys too.

What settings? I've been searching and I have absolutly no clue what settings page your talking about. Can anyone help.
D-ocons
Newbie Caller
Hace 3 años
TuesdayB wrote:

This worked for all of 5 minutes. Disregard

I'll try it too. Any hope is better than none. I appreciate it!
TuesdayB
Roaming Rookie
Hace 3 años
This worked for all of 5 minutes. Disregard
TuesdayB
Roaming Rookie
Hace 3 años
Guys following this changed my NAT type from D to B on the switch. Haven't tested with game yet but let me know if this works out for you guys too.
TuesdayB
Roaming Rookie
Hace 3 años
D-ocons wrote:

So is that just it?

If you have T-Mobile 5G internet. You can't play most games online with Nintendo switch?

I just found this on another forum and it changed my NAT type from D to B on the switch. I'm waiting for my brothers to wake up and see if it'll actually connect this time. I'll update if it works but in the meantime this is what I found and followed.