R2511-HP MSR Router Series Layer 3 - IP Routing Configuration Guide(V5)
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Graceful Restart ensures the continuity of packet forwarding when a routing protocol restarts or an
active/standby 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.
Configuring GR helper
You can configure the GR helper capability on a GR helper.
To configure GR helper:
Ste
p
Command
Remarks
1. Enter system view.
system-view N/A
2. Enter OSPFv3 view.
ospfv3 [ process-id ]
N/A
3. Enable the GR helper
capability.
graceful-restart helper enable
Optional.
Enabled by default.
4. Enable strict LSA
checking.
graceful-restart helper
strict-lsa-checking
Optional.
Disabled by default.
Configuring BFD for OSPFv3
Bidirectional forwarding detection (BFD) provides a mechanism to quickly detect the connectivity of links
between OSPFv3 neighbors, thus to improve the convergence speed of OSPFv3.
After discovering neighbors by sending hello packets, OSPFv3 notifies BFD of the neighbor addresses,
and BFD uses these addresses to establish sessions. Before a BFD session is established, it is in the down
state. In this state, BFD control packets are sent at an interval of no less than 1 second to reduce BFD
control packet traffic. After the BFD session is established, BFD control packets are sent at the negotiated
interval, thereby implementing fast fault detection.
To configure BFD for OSPFv3, you need to configure OSPFv3 first.
For more information about BFD, see High Availability Configuration Guide.
To configure BFD for OSPFv3:
Ste
p
Command
Remarks
1. Enter system view.
system-view N/A
2. Enter OSPFv3 view.
ospfv3 [ process-id ]
N/A
3. Specify a router ID.
router-id router-id N/A
4. Quit the OSPFv3 view.
quit N/A
5. Enter interface view.
interface interface-type
interface-number
N/A
6. Enable an OSPFv3 process
on the interface.
ospfv3 process-id area area-id
[ instance instance-id ]
Not enabled by default.
7. Enable BFD on the interface.
ospfv3 bfd enable [ instance
instance-id ]
Not enabled by default.