H3C S9500 Series Operation Manual page 274

Operation Manual – Routing Protocol
H3C S9500 Series Routing Switches
Only when the current DR is offline, will the DR be changed. Shut down Switch A, and
execute the display ospf peer command on Switch D to display its neighbors. Note
that the original BDR (Switch C) becomes the DR, and Switch B is BDR now.
If all Switches on the network are removed and added back again, Switch B will be
elected as the DR (with the priority of 200), and Switch A becomes the BDR (with a
priority of 100). To switch off and restart all of the switches will bring about a new round
of DR/BDR selection.
4.4.2 Configuring OSPF Virtual Link
I. Network requirements
In Figure 4-4, Area 2 and Area 0 are not directly connected. Area 1 is required to be
taken as a transit area for connecting Area 2 and Area 0. Configure a virtual link
between Switch B and Switch C in Area 1.
II. Network diagram
Area 1 Area 1
Figure 4-4 Network diagram for OSPF virtual link configuration
III. Configuration procedure
# Configure Switch A
[Switch A] interface Vlan-interface 1
[Switch A-Vlan-interface1] ip address 196.1.1.1 255.255.255.0
[Switch A] router id 1.1.1.1
[Switch A] ospf
[Switch A-ospf-1] area 0
[Switch A-ospf-1-area-0.0.0.0] network 196.1.1.0 0.0.0.255
# Configure Switch B
[Switch B] interface vlan-interface 7
[Switch B-Vlan-interface7] ip address 196.1.1.2 255.255.255.0
Switch A Switch A
1.1.1.1 1.1.1.1
Area 0 Area 0
196.1.1.1/24 196.1.1.1/24
196.1.1.2/24 196.1.1.2/24
Switch B Switch B
2.2.2.2 2.2.2.2
Virtual Virtual
Link Link
Switch C Switch C
3.3.3.3 3.3.3.3
197.1.1.2/24 197.1.1.2/24
197.1.1.1/24 197.1.1.1/24
152.1.1.1/24 152.1.1.1/24
Area 2 Area 2
4-32
Chapter 4 OSPF Configuration