OSPF- Area dummy area message

Hi,

I am having a strange OSPF behavior, may be this is the way to prevent loop
in OSPF.

This is the lab scenario.

R5 is acting as a Hub and it is connected to R2 and R4 via
point-to-multipoint link and to R1 via point-to-point link. R1 and R2 are
connected to R6 via EIGRP and redistributing EIGRP routes into R1 and R2.

Now, as per my understanding on R1 and R2 the external LSA must be present
in database both on R1 (must be from R2 and its own) and on R2 ( From R1
and it own.)
But on both routers the database showing their own external LSA and does
not showing external LSA from others.

After doing the debugging, i found that the routes are removed from the
database due to OSPF set the routes to Area dummy area and increased the
metric to 167772 learned from other borders routers

Debuggin done on R1

These routes are from R1

OSPF process partial spfQ LSA id 54.1.3.0: mask 255.255.255.0, type 5
adv_rtr 150.1.1.1, age 3600, seq 0x80000002 (Area dummy area)
OSPF: Start partial processing Type 5 External LSA 54.1.3.0, mask
255.255.255.0, adv 150.1.1.1, age 3600, seq 0x80000002, metric 167772

Rack1R2#show ip ospf database external 204.12.1.0

            OSPF Router with ID (150.1.2.2) (Process ID 1)

                Type-5 AS External Link States

  LS age: 968
  Options: (No TOS-capability, DC)
  LS Type: AS External Link
  Link State ID: 204.12.1.0 (External Network Number )
  Advertising Router: 150.1.2.2
  LS Seq Number: 80000009
  Checksum: 0x1165
  Length: 36
  Network Mask: /24
        Metric Type: 1 (Comparable directly to link state metric)
        TOS: 0
        Metric: 20
        Forward Address: 0.0.0.0
        External Route Tag: 300

Thanks in advance.

Rgds,

Rajesh

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Received on Mon Nov 26 2012 - 17:09:25 ART