HP 6125G HP 6125G & 6125G/XG Blade Switches Layer 3 - IP Routing Confi - Page 228

IMPORTANT: You cannot configure OSPFv3 GR after configuring OSPFv3 virtual links, because they are not supported at the same time. Graceful Restart ensures the continuity of packet forwarding when a routing protocol restarts or a master/slave switchover occurs: • GR Restarter-Graceful restarting router. It must be Graceful Restart capable. • GR Helper-The neighbor of the GR Restarter. It helps the GR Restarter to complete the GR process. To prevent service interruption after a master/slave switchover, a GR Restarter running OSPFv3 must complete the following tasks: • Keep the GR Restarter forwarding entries stable during reboot. • Establish all adjacencies and obtain complete topology information after reboot. After the master/slave switchover, the GR Restarter sends a Grace-LSA to tell its neighbors that it performs a GR. Upon receiving the Grace-LSA, the neighbors with the GR Helper capability enter the helper mode (and are then called "GR Helpers"). Then, the GR Restarter retrieves its adjacencies and LSDB with the help of the GR Helpers. Configuring GR Restarter You can configure the GR Restarter capability on a GR Restarter. To configure GR Restarter: Step 1. Enter system view. 2. Enter OSPFv3 view. 3. Enable the GR capability. 4. Configure the GR interval. Command system-view ospfv3 [ process-id ] graceful-restart enable graceful-restart interval interval-value Remarks N/A N/A Disabled by default. Optional. 120 seconds by default. Configuring GR Helper You can configure the GR Helper capability on a GR Helper. To configure GR Helper Step 1. Enter system view. 2. Enter OSPFv3 view. Command system-view ospfv3 [ process-id ] 3. Enable the GR Helper capability. graceful-restart helper enable 4. Enable strict LSA checking. graceful-restart helper strict-lsa-checking Remarks N/A N/A Optional. Enabled by default. Optional. Disabled by default. 218