How to Set MSS Clamping for VPN on USG FLEX H Series?

Zyxel_Cooldia

Question:

How to Set MSS Clamping for VPN Interface on USG FLEX H Series?

Answer:

The MSS (Maximum Segment Size) clamping setting for VPN interface is not directly configurable via the GUI on the USG FLEX H series. However, this can be performed using CLI commands.

Steps to set MSS Clamping via CLI:

1. Access the device's CLI.
2. Enter configuration mode by typing: edit running
3. Navigate to the VPN settings: vrf main ike vpn xxxxxx tcpmss yyyy

Replace xxxxxx with your VPN tunnel name (you can use the Tab key to autofill the command). Replace yyyy with the desired MSS value.

4. Commit the changes by typing: commit

5. Save the configuration to the startup file by typing: copy running startup

When prompted to overwrite the startup configuration, type y and press Enter.