Which command can be used to view the number of times the SPF algorithm has been executed?

Which command can be used to view the number of times the SPF algorithm has been executed?

  • show ip ospf
  • show ip ospf interface
  • show ip ospf database
  • show ip ospf neighbor
Explanation:
The show ip ospf command can be used to view the number of times the SPF algorithm has been executed, as shown in the last line of the following output:

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300-410 Part 05 Q18 069

The show ip ospf interface command can be used to view neighbor adjacencies. A partial output of the command is shown below. It will not show the number of times the SPF algorithm has been executed.

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300-410 Part 05 Q18 070

The show ip ospf neighbor command can also be used to view neighbor adjacencies, although its output is slightly different from the show ip ospf interface command. A partial output of the show ip ospf neighbor command is shown below. It also does not show the number of times the SPF algorithm was executed.

300-410 Part 05 Q18 071

300-410 Part 05 Q18 071

The show ip ospf database command does not show the number of times the SPF algorithm has executed. It shows the contents of OSPF database. Partial output is shown below:

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300-410 Part 05 Q18 072

You can make the command output more specific by using parameters with the show ip ospf database command. For example, to view only Type 5 LSAs in the database, you would execute the show ip ospf database external command. Since all Type 5 LSAs are from external networks, this keyword will trim the output to only those types of LSAs. When Type 5 (or external) routes are placed in the database, the next hop address will be 0.0.0.0, which makes it appear as if it is a default route. What this really means is that any traffic that needs to go to that external network will be sent to the router that originated the advertisement (the ASBR).

Objective:
Layer 3 Technologies
Sub-Objective:
Configure and verify OSPF operations

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