We are receiving many reports about extremely slow and unstable GlobalProtect connections with some internet providers in Marburg .
The providers don’t provide native IPv4 addresses in consumer tariffs, IPv4 packets are tunneled via carrier-grade NAT (Dual Stack lite). This causes packet fragmentation. End user are unable to connect to VPN or if the connection was etsablished, it is very slow (like a modem) an not stable.
As IPv4 address blocks are becoming depleted, even in other countries like Great Britain our affiliates reporting first issues with Dual Stack lite.
Temporary decreasing the MTU size may could help for a limited time but is not a solution. MTU size varies day to day and with our monthly driver updates, we automatically changes the settings back to "standard".
In the past year, we found a temporary solution. Customers were able to call the provider’s hotline and request DualStack configuration for additional 3€/month, but it’s not guaranteed to be persistent.
We were facing the same issue with DSLite.
You can set the MTU on the tunnel interface on the firewall (Advanced tab), a value of 1300 works fine for us.
Click Accept as Solution to acknowledge that the answer to your question has been provided.
The button appears next to the replies on topics you’ve started. The member who gave the solution and all future visitors to this topic will appreciate it!
These simple actions take just seconds of your time, but go a long way in showing appreciation for community members and the Live Community as a whole!
The Live Community thanks you for your participation!