Difference between revisions of "OSPF"
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ospftest-ap#show run | ospftest-ap#show run | ||
Common commands to use for troubleshooting OSPF include the "show ip ospf neighbor" and "show ip ospf routes" commands. | |||
ospftest-ap# sh ip ospf neighbor | |||
Neighbor ID Pri State Dead Time Address Interface RXmtL RqstL DBsmL | |||
10.0.1.7 1 Full/Backup 00:00:35 10.8.1.1 wpci0:10.8.1.2 0 0 0 | |||
10.8.3.2 1 Full/DR 00:00:34 10.8.3.2 wpcm0:10.8.3.1 0 0 0 | |||
ospftest-ap# | |||
This shows all neighbors to an OSPF router. The "Full" designation indicates that routes are being exchanged between this router and the neighbor routers. If you see the "Init" state continuously, there may be a configuration issue on one of the routers. | |||
The "show ip ospf routes" command will show all of the routes that this OSPF router has in its routing table. | |||
Caveats: | |||
- Certain via-rhine network cards will not broadcast network traffic, and have problems with the standard OSPF configuration. You will have to set up a unicast network broadcast to adjacent routers and vice versa if you are using these cards. | |||
- The broadcast traffic for OSPF will go out using the first IP address configuration on an interface. | |||
- OSPF traffic will not propagate between two different routers on a PTMP wireless connection with Intercell relay turned off | |||
- OSPF is very sensitive to network timing changes. On StarOS it is encouraged to either leave the automatic time updates set to on or off - do not mix these settings, or it will cause OSPF problems. |
Revision as of 11:35, 24 January 2008
OSPF stands for Open Shortest Path First. On StarOS, this is implemented through the use of the Quagga routing daemon. Essentially, the daemon runs on two routers and they use the broacast addresses to announce routes between routers. This is an excellent way to dynamically distribute routes across a complex routed network.
OSPF configuration uses a configuration prompt that works in a very similar manner to a Cisco router configuration. Once logged in, you have to use the "enable" command to get into a privileged mode which will allow for modification of the configuration. Each line in the configuration file is enabled by simply typing the command. Disabling interfaces or commands is accomplished by putting the word "no" in front of the command. When the configuration is comppleted, use the "write memory" command to copy the configuration to memory. If you do not write the config to memory, OSPF will not retain the configuration.
Here is an example of a simple OSPF configuration:
Current configuration: ! hostname ospftest-ap password yourpassword ! ! ! interface eth0 ! interface wpci0 ! interface wpcm0 ! router ospf ospf router-id 10.1.1.1 redistribute connected redistribute static network 10.0.0.0/8 area 0.0.0.0 ! access-list vtylist permit 127.0.0.1/32 access-list vtylist permit 10.0.0.0/8 access-list vtylist deny any ! line vty access-class vtylist ! end
Here are the commands that would be run to set this up:
hostname>en
hostname#conf t
hostname(config)#password yourpassword
hostname(config)#hostname ospftest-ap
ospftest-ap(config)#router ospf
ospftest-ap(config-router)#ospf router-id 10.1.1.1
ospftest-ap(config-router)#redistribute connected
ospftest-ap(config-router)#redistribute static
ospftest-ap(config-router)#network 10.0.0.0/8 area 0
ospftest-ap(config-router)#exit
ospftest-ap(config)#no access-list vtylist deny any
ospftest-ap(config)#access-list vtylist permit 10.0.0.0/8
ospftest-ap(config)#access-list vtylist deny any
ospftest-ap(config)#exit
ospftest-ap#write memory
ospftest-ap#show run
Common commands to use for troubleshooting OSPF include the "show ip ospf neighbor" and "show ip ospf routes" commands.
ospftest-ap# sh ip ospf neighbor Neighbor ID Pri State Dead Time Address Interface RXmtL RqstL DBsmL 10.0.1.7 1 Full/Backup 00:00:35 10.8.1.1 wpci0:10.8.1.2 0 0 0 10.8.3.2 1 Full/DR 00:00:34 10.8.3.2 wpcm0:10.8.3.1 0 0 0 ospftest-ap#
This shows all neighbors to an OSPF router. The "Full" designation indicates that routes are being exchanged between this router and the neighbor routers. If you see the "Init" state continuously, there may be a configuration issue on one of the routers.
The "show ip ospf routes" command will show all of the routes that this OSPF router has in its routing table.
Caveats:
- Certain via-rhine network cards will not broadcast network traffic, and have problems with the standard OSPF configuration. You will have to set up a unicast network broadcast to adjacent routers and vice versa if you are using these cards.
- The broadcast traffic for OSPF will go out using the first IP address configuration on an interface.
- OSPF traffic will not propagate between two different routers on a PTMP wireless connection with Intercell relay turned off
- OSPF is very sensitive to network timing changes. On StarOS it is encouraged to either leave the automatic time updates set to on or off - do not mix these settings, or it will cause OSPF problems.