Mixing Statically Configured And Auto-Discovered Pseudowires In A Vpls; Resiliency Schemes - Alcatel-Lucent 7750 SR Manual

Mixing Statically Configured and Auto-Discovered Pseudowires in a VPLS

The services implementation allows for manually provisioned and auto-discovered pseudowire
(SDP bindings) to coexist in the same VPLS instance (for example, both FEC128 and FEC 129 are
supported). This allows for gradual introduction of auto discovery into an existing VPLS
deployment.
As FEC 128 and 129 represent different addressing schemes, it is important to make sure that only
one is used at any point in time between the same two VPLS instances. Otherwise, both
pseudowires may become active causing a loop that might adversely impact the correct
functioning of the service. It is recommended that FEC128 pseudowire be disabled as soon as the
FEC129 addressing scheme is introduced in a portion of the network. Alternatively, RSTP may be
used during the migration as a safety mechanism to provide additional protection against
operational errors.

Resiliency Schemes

The use of BGP AD on the network side, or in the backbone, does not affect the different
resiliency schemes Alcatel-Lucent has developed in the access network. This means that both
Multi-Chassis Link Aggregation (MC-LAG) and Management-VPLS (M-VPLS) can still be used.
BGP AD may coexist with Hierarchical-VPLS (H-VPLS) resiliency schemes (for example, dual
homed MTU-s devices to different PE-rs nodes) using existing methods (M-VPLS and statically
configured Active/Standby pseudowire endpoint).
If provisioned SDPs are used by BGP AD, M-VPLS may be employed to provide loop avoidance.
However, it is currently not possible to auto-discover active/standby pseudowires and to
instantiate the related endpoint.
7750 SR OS Services Guide
Virtual Private LAN Services
Page 489