VPN issues

I had this issue and resolved it with my job's IT team.  You have to change everything to just IPv4.  I am a complete layperson, but here are the steps to resolve for me, using Windows 10 and a CISCO VPN:

Remove IPv6 from your Wifi:

1. Go to Control Panel
2. Click “Network and Sharing”
3. Click the hyperlink after “Connections” for the section named after your WIFI Hub
4. Click the “Properties” button in the bottom left of the pop-up box
5. De-select “Internet Protocol Version 6 (TCP/IPv6)”

Remove IPv6 from your VPN:

1. Click Start
2. Click Settings (looks like a gear)
3. Click Network and Internet
4. Select “Change Adapter Options”
5. Right click on your VPN
6. Select Properties
7. De-select “Internet Protocol Version 6 (TCP/IPv6)”

I know that the Wifi and VPN Propiedades screen can be accessed either way, but I wanted to show that there are two ways of accessing them.  

Hope this helps someone out there!

I too use GlobalProtect which worked fine for 1 day then quit. I resolved the issue by setting the MTU on the PANPG adapter to 1340. However, I am going to try your fix to see if that resolves the issue with the default packet size. I  am getting so much intermittent latency with this service that it is just not working for working from home. But it is great when it works. 

Just adding to this - I want to use this service so badly!  Currently on my 4th day and still have Comcast while I was testing and found this issue.  Unfortunately, it's a deal breaker and Ill have to go back to Comcast if this doesn't work, my wife is a nurse and needs to be able to VPN to work, as do I for my job.

Any updates on this T-Mobile?

If they plan to roll this out for business and personal use they need to fix this or it's going to be a massive fail. I've tried factory resetting the router 10+ times and still can't get the update to push. For now I'm  still using my phone hotspot but the whole point of subscribing to T Mobile Home Internet was because it won't play nice on Teams calls/meetings.

I have had the T-Mobile Home Internet Service for about 2 months now and have been fighting non-stop with the VPN issues. I use Cisco AnyConnect for my work and constantly have issues with applications needed for work, mostly Microsoft Teams. When NOT connected to the VPN my download is about 75mbps and upload about 25mbps, all very good numbers. However, once connected to Cisco AnyConnect those numbers come down to almost a crashing halt of 2.5mbps down and 2.0mbps up… it is absolutely awful and quite honestly embarrassing because I have to be on Microsoft Teams all day including conferences.

I've talked to the tech support and it was elevated to a second tier, but that resulted in no solution. Their belief is that the VPN was the problem and that I needed to speak with my employer's IT department about it… so I did. I opened up various tickets through my employer and went in to the office so they could do additional diagnosing. They could not find anything wrong, in fact, had me log in to the VPN via their network and it worked just fine. 

I have starlink service on order and hope to have it here in a month. Ideally for the cost and what I anticipated being great performance by T-Mobile, I would prefer to keep T-Mobile. However, I simply CANNOT wait much longer especially if the company appears to be denying even an issue.

Hope T-Mobile comes to the rescue.

eps414 wrote:

What version firmware are you on?

also, what did you end up setting your MTU to for GPVpn?

My configuration is this:
Host: Apple Mac OS X 10.15.7
VPN:
Provider: GlobalProtect v5.0.9–15 Palo Alto Networks
Tunnel Mode: IPSEC
Gateway para Internet residencial de T-Mobile:
Model: 5G21–12-A Grey
Hardware Version: 3TG00739AABB
Versión de software: 1.2003.03.0178

And the MTU I set to 1350, using this command “sudo ifconfig gpd0 mtu 1350”

Update: It's now Thursday morning. T-Mobile support had promised to call me back on Tuesday morning with an update (they didn't). I checked today and saw that I had finally been downgraded to firmware 168. I tried my Global Protect VPN and it actually works! I'll try working the rest of the day on that to see if it continues to work.

My Global Protect VPN worked for a second day so I started to feel a little better. However, there's more lag in the T-Mobile connection, which was frustrating when trying to type things over the VPN connection (Cox ping times for me are always <10ms and jitter is pretty low, too; with T-Mobile, ping times varied a lot between 35 and 80ms). I switched back to my Cox connection to get work done this afternoon as the T-Mobile latency bugged me. Note: the T-Mobile latency wasn't horrible for me. I usually find things <100ms to not be bad, but <10ms is a lot better.

I started looking at other issues with T-Mobile:

• Lack of configurability. I ultimately wanted to just replace my cable modem with it, but the software is crippled (there are other threads on that) so that you can't connect it to a home router, etc.
• They told me I could purchase landline service through the RJ-11 jack on the back, but when I tried to sign up for it, I got a different story, with most people being terribly confused. Most people thought I was talking about the T-Mobile Line Link service (which was discontinued in April, and not everyone there knew about it). They were telling me I needed to get a Line Link adapter and really didn't know about the 5G product. 
• Poor support. Sometimes I called and was told I'd get a call back in 1 or 2 hours. The people you talk to on the phone can only submit tickets and wait 24-72 hours for engineering to do something about it. They can't get a status on it, etc. I was incorrectly told to go to physical T-Mobile stores who have no ability to do anything about T-Mobile Home Internet other than call T-Mobile customer service.

To their credit, there are a few random knowledgeable people there. They did get my Global Protect VPN working finally when they did the firmware downgrade.

Ultimately, I ended up sending back the device today. I guess I'm stuck with Cox for now. Several years ago, Cox used to be stellar, but lots of things there have gone downhill while the prices constantly climb. I guess it's good to be a monopoly.

This fixed it for me. I had problems using WireGuard VPN. I couldn't reach many sites and it was very slow.

https://amithkumarg.medium.com/resolved-t-mobile-home-internet-vpn-issue-2f5ca594c23e

Short version is you need to lower the “MTU” setting on your machine’s network adapter

For me on my macbook, it was the “wifi” “en0” device, either at the terminal with “sudo ifconfig en0 mtu 1350” or going to “Network Preferences > Advanced > Hardware” and manually configuring the MTU to 1350. 

Been fighting this issue for a couple of months. On my windows 10 laptop connected to Cisco Anyconnect VPN I had the IT administrator reduce my MTU to 1350 via this command

netsh interface ipv4 set subinterface “Network Name” mtu=1350 store=persistent 

substitute Network Name with your whatever your actual connection in.  Mine was Ethernet 2.

It worked.  I’m connected to VPN and have blazing speed.