OSPF over DMVPN Adv Tech Lab question

The configuration shows the following

R1 - R2:
interface Tunnel0
ip ospf 1 area 0
ip ospf network non-broadcast
ip ospf priority 0
!
interface Loopback0
ip ospf 1 area 0

But yet, in the solution, it is showing State BDR, Priority 1, but yet we were supposed to configure a priority of 0, so not sure how it has a priority of 1. From what I can see, this should say DROTHER and 0 correct?

R1#show ip ospf interface tunnel0
Tunnel0 is up, line protocol is up
Internet Address 155.1.0.1/24, Area 0, Attached via Interface Enable
Process ID 1, Router ID 150.1.1.1, Network Type NON_BROADCAST, Cost: 1000
Topology-MTID Cost Disabled Shutdown Topology Name
0 1000 no no Base
Enabled by interface config, including secondary ip addresses
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 150.1.5.5, Interface address 155.1.0.5
No backup designated router on this network
Timer intervals configured, Hello 30, Dead 120, Wait 120, Retransmit 5
oob-resync timeout 120
Hello due in 00:00:08
Supports Link-local Signaling (LLS)

Comments

  • Also, it says the following "When adjacency is established in area 0, Inter-Area routing advertisements can be propagated throughout the entire topology. This is because R1, R2, R3, R4, and R5 are now ABRs and can originate the Network Summary LSA (LSA 3) describing Inter-Area routes to the other neighbors in their attached areas. From the show ip ospf database output on R5, the Summary Net link States (Area 0) shows ABRs that are advertising information from other areas into area 0. In this case, R3 and R4 are advertising their Loopbacks; note that R5 does not know the area these prefixes were injected into."

    How are R1/R2 ABR's? It should tell you if they are an ABR in the "show ip ospf" output, and clearly R1/R2 do not.

    Also, the output for LSA3 only shows R3/R4 which is correct because they are the only ones.

    R2 - no ABR info listed

    R2#sho ip ospf
    Routing Process "ospf 1" with ID 150.1.2.2
    Start time: 00:09:59.844, Time elapsed: 01:12:16.570
    Supports only single TOS(TOS0) routes
    Supports opaque LSA
    Supports Link-local Signaling (LLS)
    Supports area transit capability
    Supports NSSA (compatible with RFC 3101)
    Supports Database Exchange Summary List Optimization (RFC 5243)
    Event-log enabled, Maximum number of events: 1000, Mode: cyclic
    Router is not originating router-LSAs with maximum metric
    Initial SPF schedule delay 5000 msecs
    Minimum hold time between two consecutive SPFs 10000 msecs
    Maximum wait time between two consecutive SPFs 10000 msecs

    R3 - shows this is an ABR

    R3#sho ip ospf
    Routing Process "ospf 1" with ID 150.1.3.3
    Start time: 00:18:51.125, Time elapsed: 00:58:23.621
    Supports only single TOS(TOS0) routes
    Supports opaque LSA
    Supports Link-local Signaling (LLS)
    Supports area transit capability
    Supports NSSA (compatible with RFC 3101)
    Supports Database Exchange Summary List Optimization (RFC 5243)
    Event-log enabled, Maximum number of events: 1000, Mode: cyclic
    It is an area border router <-------- shows right here

    If R1/R2 are ABR's why are there no LSA3's listed in the following output?

    R5#sho ip ospf data

            OSPF Router with ID (150.1.5.5) (Process ID 1)
    
        Router Link States (Area 0)
    

    Link ID ADV Router Age Seq# Checksum Link count
    150.1.1.1 150.1.1.1 875 0x8000000E 0x0026F7 2
    150.1.2.2 150.1.2.2 762 0x8000000B 0x0037E2 2
    150.1.3.3 150.1.3.3 899 0x8000000C 0x00506F 1
    150.1.4.4 150.1.4.4 899 0x80000006 0x004878 1
    150.1.5.5 150.1.5.5 924 0x80000012 0x001951 6

        Net Link States (Area 0)
    

    Link ID ADV Router Age Seq# Checksum
    155.1.0.5 150.1.5.5 128 0x80000005 0x00735F

        Summary Net Link States (Area 0)
    

    Link ID ADV Router Age Seq# Checksum
    150.1.3.3 150.1.3.3 1991 0x80000001 0x0028D8
    150.1.4.4 150.1.4.4 276 0x80000002 0x0004F7

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