Technical Documentation

Option: Configuring the Spanning Tree Protocol and VPLS on MX Series Routers

If multiple routers on a customer site are connected to the same PE, you should enable the Spanning Tree Protocol on that PE. To configure RSTP or MSTP and VPLS simultaneously, include the rstp or mstp statement at the [edit instance-type layer2-control] hierarchy level:

[edit]instance-type layer2-control;protocols {rstp {interface interface name;force-version stp; # To run STP instead of RSTP}}

The Per-VLAN Spanning Tree (PVST) protocol maintains a separate spanning-tree instance for each VLAN. To enable PVST for a specific VLAN ID, there should be a VPLS instance with that VLAN ID and all of the logical interfaces assigned to that instance should have the same matching VLAN ID. To configure PVST with VPLS, include the vstp statement at the [edit instance-type layer2-control] hierarchy level:

[edit]instance-type layer2-control;protocols {vstp {interface interface name;vlan vlan-id;}}

If you want only STP to run on a device, you can configure STP by including the force-version stp statement at the [edit protocols rstp] or [edit protocols vstp] hierarchy level:

[edit]protocols {rstp {force-version stp;}}

For more information about the Spanning Tree Protocol (VSTP, MSTP, RSTP, or STP), see the MX Series Solutions Guide and the JUNOS Routing Protocols Configuration Guide.


Published: 2010-04-15