To enable key numbers and fragmentation on GRE tunnels (as described in Configuring a Key Number on GRE Tunnels and Enabling Fragmentation on GRE Tunnels), you must also specify an MTU setting for the tunnel.
To specify an MTU setting for the tunnel, include the mtu statement:
- mtu bytes;
You can include this statement at the following hierarchy levels:
For more information about MTU settings, see the JUNOS Network Interfaces Configuration Guide.