R21xx-HP FlexFabric 11900 Layer 3 IP Routing Configuration Guide

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Enabling OSPF ISPF
When the topology changes, Incremental Shortest Path First (ISPF) computes only the affected part of the
SPT, instead of the entire SPT.
To enable OSPF ISPF:
Ste
p
Command Remarks
1. Enter system view.
system-view N/A
2. Enter OSPF view.
ospf [ process-id | router-id router-id |
vpn-instance vpn-instance-name ] *
N/A
3. Enable OSPF ISPF.
ispf enable
By default, OSPF ISPF is
enabled.
Configuring OSPF GR
GR ensures forwarding continuity when a routing protocol restarts or an active/standby switchover
occurs.
Two routers are required to complete a GR process. The following are router roles in a GR process.
• GR Restarter—Graceful restarting router. It must have GR capability.
• GR Helper—A neighbor of the GR Restarter. It helps the GR Restarter to complete the GR process.
OSPF GR has the following types:
• IETF GR—Uses Opaque LSAs to implement GR.
• Non-IETF GR—Uses link local signaling (LLS) to advertise GR capability and uses out of band
synchronization to synchronize the LSDB.
A device can act as a GR Restarter and GR Helper at the same time.
Configuring the OSPF GR Restarter
You can configure the IETF or non IETF OSPF GR Restarter.
Configuring the IETF OSPF GR Restarter
Ste
p
Command Remarks
1. Enter system view. system-view N/A
2. Enable OSPF and enter its
view.
ospf [ process-id | router-id
router-id | vpn-instance
vpn-instance-name ] *
N/A
3. Enable opaque LSA reception
and advertisement capability.
opaque-capability enable
By default, opaque LSA reception
and advertisement capability is
enabled.