Network OS Administration Guide

Supporting Network OS 6.0.1a

Part Number: 53-1003768-04

HA failover

Warm-recovery High Availability (HA) failover is supported for both fabric cluster mode and logical chassis cluster mode.

Warm recovery includes the following behaviors:

  • No data path disruption results for Layer 2, Layer 3 and FCoE traffic.
  • All Layer 2 and Layer 3 control protocol states are retained.
  • The topology state and interface state are retained.
  • All running configuration is retained (including the last accepted user configuration just before HA failover).
  • During a warm recovery, the principal switch in a logical chassis cluster remains the principal switch. After warm recovery, the principal switch reestablishes cluster management layer connection with other switches and reforms the cluster.
  • A secondary switch in a logical chassis cluster reestablishes cluster management layer connection with the principal switch and rejoins the cluster after warm recovery.
  • If you run a reload command on an active MM, the principal switch in a logical chassis cluster goes into cold recovery and comes back up as a secondary switch.
  • HA behavior during In-service software upgrades is the same as for warm-recovery failover.
NOTE
The ha failover command is supported only on a dual-management-module chassis system.