Watchguard V10 User Manual page 241

4
To enable the Firebox Vclass appliance to log for this
particular security policy, click Enable Per-policy Log.
The traffic log setting
information on configuring logging, see "Log Settings" on
page 383.
5 Click the MSS tab.
6
To enable per-Policy TCP MSS (Maximum Segment
Size), click Use Per-policy Settings.
Firebox Vclass User Guide
Using the Advanced Settings
must
also be enabled. For more
209