3com 8807 사용자 가이드
Typical OSPF Configuration Example
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On Switch A, execute the display ospf peer command to display the OSPF peers.
Note that Switch A has three peers.
Note that Switch A has three peers.
The state of each peer is full, which means that adjacency is set up between
Switch A and each peer. (Switch A and Switch C should set up adjacencies with all
the routers on the network for them to be DR and BDR on the network
respectively.) Switch A is DR, while Switch C is BDR on the network. And all the
other neighbors are DR others (which means that they are neither DRs nor BDRs).
Switch A and each peer. (Switch A and Switch C should set up adjacencies with all
the routers on the network for them to be DR and BDR on the network
respectively.) Switch A is DR, while Switch C is BDR on the network. And all the
other neighbors are DR others (which means that they are neither DRs nor BDRs).
# Change the priority of Switch B to 200
[Switch B-Vlan-interface2000] ospf dr-priority 200
On Switch A, execute the display ospf peer command to show its OSPF
neighbors. Note the priority of Switch B has changed to 200, but it is still not the
DR.
neighbors. Note the priority of Switch B has changed to 200, but it is still not the
DR.
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.
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.
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.
Configuring OSPF
Virtual Link
Network requirements
In Figure 84, 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.
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.
Network diagram
Figure 84 Network diagram for OSPF virtual link configuration
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Switch A
1.1.1.1
Switch B
2.2.2.2
Virtual
Link
Link
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Area 2
Area 1
Area 0
Switch C
3.3.3.3
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