Showing results for 
Show  only  | Search instead for 
Did you mean: 

VPN connected but cannot reach internal devices

Level 1
1 of 5

Hey guys,


I set up the Swisscom VPN and can establish a connection. However, once connected, I cannot reach ANY devices on my internal network, not even the router. It turns out I have a 32-bit subnet mask (, so I'm essentially in a network with... myself. If I add a static route and use my assigned internal (VPN) IP address as the gateway, everything works fine.


My question is: why am I getting a 32-bit mask and how can I get a regular 24-bit mask so I needn't create a static route every time?


Thanks 🙂


4 Comments 4
Level 1
2 of 5






If you are testing the vpn from home with a PC etc. in Wi-Fi it will not work. To test the vpn you must be in 4G or 5G connection.



Cordially Doremi

Mystrom & La pomme croquée
Level 1
3 of 5

Thanks! I'm abroad right now, so definitely dialing into my network from outside of it.

Black Mamba
Level 1
4 of 5



thanks for contribution and the feedback


to complete the answer / solution @Doremi 


this recent discussion can help

Report on good VDSL2 experience with Zyxel XMG3927... | Swisscom Community

post @lucaberta 27.11.2020 17:03

" ... The IPv4 Mask Length is 0, which means that the whole IPv4 address (32 bits) is mapped in the IPv6 address.

The Service Provider IPv6 Prefix is used as the main supernet in which 6RD maps the IPv4 32 bits plus the local interface addresses. ... "


also in the german Community

XMG3927-B50A u. Wingo?! | Swisscom Community

the first post 17.03.2020 22:50

" ... Für IPv6 kannst du 6RD konfigurieren, indem du als Gateway, 2a02:21b0::/32 als IPv6-Netzwerk und eine Netzmaske (bit mask length) IPv4 von 0 verwendest. Die MTU ist 1480 Bytes. ... "

" ... You can configure 6RD for IPv6 by using as gateway, 2a02: 21b0 :: / 32 as IPv6 network and a network mask (bit mask length) IPv4 of 0. The MTU is 1480 bytes. ... "

Level 1
5 of 5

Thank you so much for sharing this! Honestly, I haven't been a systems engineer in many years and was never a network engineer. So IPv6 and 6RD are a little over my head.


I think I understand, though, that for VPN to work properly, I need a router over which I have more control. Could you help me understand why? VPN did work when I hotspotted myself before I left home. At that time, I must have had a proper mask, otherwise I wouldn't have been able to print the test page.


Still a little puzzled 😊

Back to top