VPN issues

  • 9 January 2021
  • 99 replies

Show first post

99 replies

I read somewhere that a new firmware greater than 1.2003.03.0168 would be coming out to address these VPN and WiFi Calling issues… anyone know?

iPhone’s WiFi calling will not work correctly with this 5G router, and also L2TP VPN will not work.

Help!  This is the best service I can get for my location… and the LTE previous (White Box) router worked for all these things… but at a slower rate.



First day with Gray tower Nokia device: model: 5G21-12W-A, Software Version:

1.2003.03.0168. It arrived at lunchtime.

I found that my speeds were variably slow even without VPN. Usually in the teens-20s for downloads. Uploads were very variable from 0.3 to 25 !  When testing locations around the planet via SurfShark VPN from 5-8pm, there were huge differences. Ping tended to be higher with farther distance from 30-200. Speeds even from the same cities varied by 300%. Never got over 42 mbps.

Via RCN in the DC area: ping 11 ms, 52 / 11 mbps,  jitter 4.8 and 0.35% packet loss via speedtest multi. Loss was zero via single connection.

Why the VPN – in case of doing any banking, like paying bills and helps to keep things more secure.

Proton VPN, free version, worked fine, but ping was in the 200s.

SurfShark VPN initially did not work. Read the prior postings here. Did the items noted below. Someplace along the way I had to change IKE2 protocol to OpenVPN TCP or WIreGuard. Used WireGuard. This was all done in the SS windows 10 software. Ping went from 52 to 54 when using SS VPN. Speeds were a bit slower 27 to 26 and 5 to 2.

First, I did the reboot via the T Mobile ISP website: No luck.

Did not do the 45 second reset.

Then I found the posting about the ipv6s and unticked the ipv6 boxes for Proton, SS, and in 1 or 2 other devices.

Still had problems with SS VPN.

Hooked up the T Mobile cylinder to my TP Link wireless device via ethernet and then ethernet from TP L to laptop, then wireless to laptop. It worked. 

Then found that the T Mobile ISP Grey tower worked with SS VPN, but after I killed the ipv6.

Then I tried turning ipv6 back on, took a while to figure out how to do this. I had to turn of SS, Then checked a website Test your IPv6. ( after making sure that all 9 network adapters had ipv6 box with a check mark in them ! Had to repeat this process several times. Also turned wireless on and off a few times too (airplane mode).

Best guess, maybe the reset and the IKE2 to TCP or WireGuard did the trick, not killing ipv6.

By 11pm I checked on the work laptop and the government VPN for NIH. It simply worked without any tweaking. Lucky I guess. Fastest speeds via T Mobile and the required gvt VPN 51 40 40 (ping, DL, Upload). Was 21 52 10 via RCN and TP L wireless router.

Also did the wireguard on the SS iphone app. Speeds were wildly variable from 22-40 DL and 1-38 upload on the iphone.

I wasted a whole day on this. I really hope my long posting here helps somebody else.



Userlevel 1

I made a post here that may help a few of you:

Basically, you must use the OpenVPN protocol with a TCP connection and a Static IP/Config method. I’m using it right now with almost no ping or speed difference and several web sites show my IP as my VPN’s IP.

VPN issues via SurfShark (SS) are quite different this am. 

Automatic type of connection, SS, IKEv2 or OpenVPN TCP, etc is now connecting via IKEv2. However this is disabling all ipv6’s. WireGuard is not working this am. TCP does work, but disables all ipv6’s. Static IP vs (typical) dynamic IP does not seem to matter with regard to speed, Windows 10 laptop. Speeds around 30s for ping (up to 100 for Seattle and Chicago, from DC), 15-20 1.5-8, DL UL. I did not google “what is my ip” to make sure it matches with my VPN.

Proton free VPN, US 3, was fine today and ping was only 41 - not the 200s; 15, 4 DL, UL.

I will assume that ipv4 vs ipv6 is of no importance for most of us (

As an aside - the enormous variability of speeds without or with VPNs is again noted. Local DC area SS VPN locale had speeds of only 3 for a while, then up to 8, vs Seattle and Chicago, along with NYC static IP at 20 DL. Ten minutes later, the speeds were different again, with local DC SS VPN locale up to 20.

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.

I tried to post a reply twice. Neither seems to have gone thru. Lost my copy. LOL.

Cannot connect via Brave browser, chrome like. So doing this via Edge. I had no issues with Cisco Any Connect on the work laptop 2 days ago. Maybe I was lucky.

Ipv6 drops out via surfshark (SS) VPN. Can someone tell us if 4 vs 6 even matters for most of us? WireGuard no longer worked yesterday. IKEv2 and TCP worked yesterday. Using IKEv2 (automatic) now on SS via Kansas City (KC). Static IP not required for SS. Using dynamic IP. Nearby VPN locations are usually slow with SS. So I have used NYC, KC, Chicago, Seattle, and a few others far from DC over the past 2 days. Could be due to vagaries of SS. Pings usually in 40s from NYC. Higher elsewhere, usually at or under 100. Speeds: DL: sometimes only 1 but often around 20. UL are all over: 1 – 5 – 10 – 25. Tested via Interestingly, yesterday Proton VPN worked with 40ms or so ping, not 200s. I have no idea what physical place I was connected to (and no idea how to find out) nor which connection protocol was used (smart, TCP, or UDP), as I forgot to check protocol.

Userlevel 1

Mine was just the MTU issue, was able to resolve it by lowering the number. If this blog can be helpful for anyone to troubleshoot and resolve the issue:


What version firmware are you on?

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

Userlevel 1

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
Provider: GlobalProtect v5.0.9–15 Palo Alto Networks
Tunnel Mode: IPSEC
T-Mobile Home Internet Gateway:
Model: 5G21–12-A Grey
Hardware Version: 3TG00739AABB
Software Version: 1.2003.03.0178

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


I’m running GP 5.2.5-66 so I think there might be some differences. 

When I run ifconfig I don’t have a gpd0, if appears as though on my Mac it is using gif0 and the default mtu setting is 1280 which is well within the 1420 threshold of the 5g21.


Figured it out. We apparently use advanced routing, so my gpd0 is actually utun0 and we have 2 vpn’s. Each vpn requires a different mtu setting, but having found the correct numbers 1330 and 1310 it now works.

Userlevel 1

Figured it out. We apparently use advanced routing, so my gpd0 is actually utun0 and we have 2 vpn’s. Each vpn requires a different mtu setting, but having found the correct numbers 1330 and 1310 it now works.

Yay! I am glad you figured it out. utun (tun short tunneling) is interface created by Mac following any VPN installation. I guess limiting that too, should work, if you don’t see gpd0 specifically.

I was wondering since you have the latest version of GP app >= 5.2.4, you should be able to update the MTU through the app settings. Check here GP documentation:

Mine was just the MTU issue, was able to resolve it by lowering the number. If this blog can be helpful for anyone to troubleshoot and resolve the issue:

Nice work. Reducing the MTU fixed my issue. I'm using Cisco AnyConnect and was able to connect but when I visited websites that required me to login using our single sign-on, it would hang after I entered my credentials. When working correctly, I get a 2FA push on my phone after successful authentication, but it would timeout before requesting the push.

I installed the gray Nokia device yesterday. It worked fine until I tried connecting to work via VPN (Global Protect). I had to get work done so I switched back to Cox. Then I tried this luck. I tried calling support. They were fairly clueless and eventually told me I need to check with my company. I asserted that my VPN worked everywhere else, including from my phone hotspot. 

They continued to assert it was my company’s problem. Then I found this thread and told the rep there are a whole bunch of people with the exact same problem that you refuse to acknowledge. Now I’m scheduled to go to a T-Mobile store tomorrow. I’m not sure what for. Maybe I can just return it then.

By the way, if you can’t get your VPN to work for any reason, there is a work around of connecting to VPN using your phone’s hotspot.

Turn on your phone’s hotspot and connect to your computer to your phone’s hotspot WIFI connection. Then, connect to your VPN. This worked for me. 

This is a small hassle, but if you want to keep TMobile Home Internet, then this is another option.  


Not necessarily.  If your VPN uses SSL, which I think CIsco ANyConnect is, you will probably be OK;  However, the hotspot on my S20G fails to connect when using an IKEv2 VPN.

I’m not having great experiences with T-Mobile. They sent me to a nearby store with an appointment. I went there to try to return the home internet device. The store said they were an independent T-Mobile store and I had to go to a corporate T-Mobile store (which fortunately wasn’t too far away). The people at the corporate T-Mobile store were trying to be helpful. I don’t think they’d ever seen the Home Internet device despite the fact that they advertise for it in the store. They told me they can’t receive the device back in the store, but that they could help me print a shipping label and maybe find a box to ship it in.

Then the people in the store had to call T-Mobile customer care (which isn’t a fun experience for them, either). After over 30 minutes on the phone with T-Mobile customer care, they passed the phone to me to talk to them. Now I got someone trying to talk me out of returning the home internet device. They asked which VPN I used (Global Protect) and said that firmware revision 168 works with Global Protect (apparently the newer version 178 that I have is worse). So they asked if they could downgrade the version in my device to 168 and try the VPN after that. They said it would take 2 hours for the downgrade and that they’d call to follow up.

Here I am 3 hours later and my firmware hasn’t been downgraded. I called again and they said ideally it takes 2 hours and confirmed that the ticket had been submitted, but he said the changes usually take place between 2 AM and 5 AM Pacific Time. 

What a mess. T-Mobile really isn’t prepared to be selling this product. 

Today (5/22/21),I was advised by tier 2 technical support that T-mobile does not support the use of VPNs through a cell phone hot spot.  This was in response to my issue of not being able to establish an IKEv2 VPN from my laptop through the hot spot on a Samsung S20G FE.   (I can do so using a different ISP without issue).   When I asked for the document that stated as much, it was not immediately avalible.  I was told I would have a copy within 72 hours.   I am not holding my breath.

I can establish an SSL-based VPN connection through the hotspot, probably because SSL has to be supported for an internet connection to be of any value whatsoever.

I consider this a material failure since T-mobile does not make this information available when one signs up.  I am considering legal action to negate the contract.

Update: It’s now Monday morning and still no firmware downgrade, although the unit finally acted like it was doing a downgrade overnight. I had to reset everything this morning. But, after getting everything set up again, I found I still have the same firmware (178). I tried calling support and it says there’s an hour wait. Not fun, T-Mobile.

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.

Userlevel 2

Just to add my (frustrating) experience with the breathtakingly bad service from TMobile. 

When I first got this device several months ago, I was unable to use my VPN (GlobalProtect) due to the tunneling protocol incompatibility.  I made several tech calls which didn’t seem to go anywhere, but for some reason it started working so I assumed they did a firmware patch.

Over the last several months, it worked (slowly) with the VPN, but I would routinely have to restart the modem to get it to work.

This week it completely broke.  I looked through this thread and ultimately made a tech call on Monday.  After a lengthy call, I ended up being told the same thing that FlyingDog was told: 178 doesn’t work so they were going to do a firmware rollback.  I was told they were submitting a ticket and someone would get back to me by Thursday.

Thursday came and went with no word and no rollback, so this morning I called back.  I ended up being on the line for 1.5 hours where I was told there was no record of the ticket to rollback and then told that firmware is something that can’t be rolled back (which is incorrect).  I ultimately ended asking to talk to a supervisor.  Their message was that they don’t have control and only know what they are told.  She did end up submitting a ticket (I have a ticket number this time) for an engineering escalation, which I assume will mean just getting the firmware rolled back.

At this point, I am also leaning toward switching over to Starlink since TMobile really is showing poor technical development and associated support.  The fact that they’d be willing to make firmware changes that completely cripple VPN usage and have technical support that can’t give you consistent answers is troubling to say the least.

It’s really too bad because other than this VPN issue the device has been working really well.  I often get download speeds near 100 Mbps and uploads around 40.

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.

Userlevel 2

Update: They did in fact end up rolling my firmware back and it is working again.


@FlyingDog For sure the performance is worse when connected to the VPN.  The previous several months this was always the case for me, I’d get about a 10-fold reduction in download speed and there was always massive latency.

Update: They did in fact end up rolling my firmware back and it is working again.


@FlyingDog For sure the performance is worse when connected to the VPN.  The previous several months this was always the case for me, I’d get about a 10-fold reduction in download speed and there was always massive latency.

My grey cylinder stopped working with my company just few days ago, maybe after they updated its firmware? How do I find out the firmware version?

Anyway, I just discovered using my cell phone hot spot as an initial connection helped me connect to company VPN using tmobile home internet. Anyone know why that might be? Here are the steps I used:

  1. Connect my Macbook Pro to cell phone hotspot
  2. Connect to VPN (GlobalProtect in my case)
  3. Switch wifi connection from cell phone hotspot to T-mobile home internet
  4. Wait for VPN to reconnect
  5. The VPN connection is now working over T-mobile home internet

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

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. 

Userlevel 1

Thanks, this worked for me after lowering the MTU to 1300 on the GlobalProtect network adapter ("Ethernet 5" on my PC)!