Examine the exhibit by pressing the Exhibit(s) button. Which configuration commands are required to correctly configure R1?

Examine the exhibit by pressing the Exhibit(s) button.

300-410 Part 04 Q15 052

300-410 Part 04 Q15 052

You are to configure R1 to belong to area 5. This area does not accept routes from the external AS or summary routes from any other internal areas. Refer to the IP addressing below.

R1 – int E0 – 192.168.5.1/24
R2 – int E0 – 192.168.5.2/24
R2 – int E1 – 192.168.0.2/24
R3 – int E0 – 192.168.0.3/24

Which configuration commands are required to correctly configure R1?

  • R1(config)# router ospf 10
    
    R1(config-router)# area 5 no-summary stub
    
    R1(config-router)# network 192.168.5.0 0.0.0.255 area 5
  • R1(config)# router ospf 5
    
    R1(config-router)# area 5 stub
    
    R1(config-router)# network 192.168.5.0 0.0.0.255 area 5
  • R1(config)# router ospf 10
    
    R1(config-router)# area 5 stub
    
    R1(config-router)# network 192.168.5.0 255.255.255.0 area 5
  • R1(config)# router ospf 5
    
    R1(config-router)# area 5 stub no-summary
    
    R1(config-router)# network 192.168.5.0 255.255.255.0 area 5
Explanation:
All routers within a stub area must be configured as stub, or adjacencies will not form. Besides the command to enable OSPF and the command to identify the area, the only other required command identifies the area as a stub. At the area border router (ABR), R2, the no-summary keyword is required. The following commands are required to configure R1:R1(config)# router ospf 5
R1(config-router)# area 5 stub
R1(config-router)# network 192.168.5.0 0.0.0.255 area 5A totally stubby area does not accept any external network LSAs (Type 5) or any inter-area summary LSAs (Types 3 and 4) from entering the area. Use the area stub command with the no-summary keyword on the ABR only to configure a totally stubby area.The correct syntax for the area stub command is shown below:Router(config-router)# area area-id stub [no-summary]Note that the optional no-summary keyword is used only on ABRs to block summary link advertisements into the stub area. This option creates a totally stubby area. It is very important to configure the command consistently on all routers within the area. OSPF sends its stub status (on or off) in its hello packets.If two neighbors have conflicting stub status, they will not form an adjacency, and you end up with no OSPF communication over that link.

300-410 Part 04 Q15 053

300-410 Part 04 Q15 053

Objective:
Layer 3 Technologies
Sub-Objective:
Configure and verify network types, area types, and router types

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