OSPF NSR configuration example
Network requirements
As shown in Figure 32, Switch S, Switch A, and Switch B belong to the same OSPF routing domain. Enable OSPF NSR on Switch S to ensure correct routing when an active/standby switchover occurs on Switch S.
Figure 32: Network diagram
Configuration procedure
Configure IP addresses and subnet masks for interfaces on the switches. (Details not shown.)
Configure OSPF on the switches to ensure the following: (Details not shown.)
Switch S, Switch A, and Switch B can communicate with each other at Layer 3.
Dynamic route update can be implemented among them with OSPF.
Enable OSPF NSR on Switch S.
<SwitchS> system-view [SwitchS] ospf 100 [SwitchS-ospf-100] non-stop-routing [SwitchS-ospf-100] quit
Verifying the configuration
# Perform an active/standby switchover on Switch S.
[SwitchS] placement reoptimize Predicted changes to the placement Program Current location New location --------------------------------------------------------------------- lb 0/0 0/0 lsm 0/0 0/0 slsp 0/0 0/0 rib6 0/0 0/0 routepolicy 0/0 0/0 rib 0/0 0/0 staticroute6 0/0 0/0 staticroute 0/0 0/0 eviisis 0/0 0/0 ospf 0/0 1/0 Continue? [y/n]:y Re-optimization of the placement start. You will be notified on completion Re-optimization of the placement complete. Use 'display placement' to view the new placement
# During the switchover period, display OSPF neighbors on Switch A to verify the neighbor relationship between Switch A and Switch S.
<SwitchA> display ospf peer
OSPF Process 1 with Router ID 2.2.2.1
Neighbor Brief Information
Area: 0.0.0.0
Router ID Address Pri Dead-Time State Interface
3.3.3.1 12.12.12.2 1 37 Full/BDR Vlan100
# Display OSPF routes on Switch A to verify if Switch A has a route to the loopback interface on Switch B.
<SwitchA> display ospf routing
OSPF Process 1 with Router ID 2.2.2.1
Routing Table
Topology base (MTID 0)
Routing for network
Destination Cost Type NextHop AdvRouter Area
44.44.44.44/32 2 Stub 12.12.12.2 4.4.4.1 0.0.0.0
14.14.14.0/24 2 Transit 12.12.12.2 4.4.4.1 0.0.0.0
22.22.22.22/32 0 Stub 22.22.22.22 2.2.2.1 0.0.0.0
12.12.12.0/24 1 Transit 12.12.12.1 2.2.2.1 0.0.0.0
Total nets: 4
Intra area: 4 Inter area: 0 ASE: 0 NSSA: 0
# Display OSPF neighbors on Switch B to verify the neighbor relationship between Switch B and Switch S.
<SwitchB> display ospf peer
OSPF Process 1 with Router ID 4.4.4.1
Neighbor Brief Information
Area: 0.0.0.0
Router ID Address Pri Dead-Time State Interface
3.3.3.1 14.14.14.2 1 39 Full/BDR Vlan200
# Display OSPF routes on Switch B to verify if Switch B has a route to the loopback interface on Switch A.
<SwitchB> display ospf routing
OSPF Process 1 with Router ID 4.4.4.1
Routing Table
Topology base (MTID 0)
Routing for network
Destination Cost Type NextHop AdvRouter Area
44.44.44.44/32 0 Stub 44.44.44.44 4.4.4.1 0.0.0.0
14.14.14.0/24 1 Transit 14.14.14.1 4.4.4.1 0.0.0.0
22.22.22.22/32 2 Stub 14.14.14.2 2.2.2.1 0.0.0.0
12.12.12.0/24 2 Transit 14.14.14.2 2.2.2.1 0.0.0.0
Total nets: 4
Intra area: 4 Inter area: 0 ASE: 0 NSSA: 0
The output shows the following when an active/standby switchover occurs on Switch S:
The neighbor relationships and routing information on Switch A and Switch B have not changed.
The traffic from Switch A to Switch B has not been impacted.