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Assigne the "192.168.103.36" router id in the OSPF(config-router) mode.

OSPF(config-router)# router-id 192.168.103.36

Cancel the assignment using the "no" prefix.

no router-id

In the "TestList1" nominate list, set deny action for the 192.168.12.0...192.168.12.255 IP-address range, the "192.168.12.0/24" value should be entered. Also add the decision to accept packets from all other addresses.

OSPF(config)# access-list TestList1 deny 192.168.12.0/24
OSPF(config)# access-list TestList1 permit any

Enable advertisement an internal link to the "192.168.103.37/24" network which located in a backbone area. There are two ways how to solve this task.

OSPF(config-router)# network 192.168.103.37/24 area 0.0.0.1
OSPF(config-router)# network 192.168.103.37/24 area 1

Display the neighbour state information.

OSPF> show neighbor
Neighbor ID     Pri   State           Dead Time   Address         Interface      RXmtL RqstL DBsmL
224.3.94.78       1   Full/Backup     00:00:26    192.168.103.36  svi1:192.168.1   

The table contains following data:

• "Neighbor ID" – neighbor router ID;
• "Pri" – priority;
• "State" – current state/status. Following states are possible:
  • • "Init" – a "Hello-packet" was recently received from a neighbor, a two-way connection is not yet established;
    • "2-Way" – a two-way connection is established between two routers, an adjacency relationship is initiated;
    • "ExStart" – the first step in adjacency relationship establishing, sets up master/slave relations;
    • "Exchange" – a router is sending it's link-state database to the neighbor;
    • "Loading" – link-state database synchronization, i.e. a router requests the neighbor for new information;
    • "Full" – neighboring relationship is established and list-state database is synchronized.
  • Current status may have following values:
    • "DR" – the router is selected to be a designated router;
    • "Backup" – the router is selected as a backup designated router;
    • "DROther" – the router is neither DR nor BDR.
• "Dead Time" – the time left for neighbor acknowledgement packet;
• "Address" – neighbor’s IP address;
• "Interface" – interface (link) through which information with neighbor is exchanged;
• "RXmtL" –  retransmit LSA quantity;
• "RqstL" – transmit LSA quantity;
• "DBsmL" – transmit LSA summary quantity.

Display database for links which were announced by transit network, and the advertising router was "192.168.45.107".

OSPF> show database network adv-router 192.168.45.107
       OSPF Router with ID (192.168.151.10)
                Net Link States (Area 0.0.0.0)
                Net Link States (Area 0.0.0.1)
  LS age: 473
  Options: 0x2  : *|-|-|-|-|-|E|*
  LS Flags: 0x6
  LS Type: network-LSA
  Link State ID: 192.168.15.1 (address of Designated Router)
  Advertising Router: 192.168.45.107
  LS Seq Number: 80000001
  Checksum: 0x9148
  Length: 32
  Network Mask: /24
        Attached Router: 192.168.45.107
        Attached Router: 192.168.151.1
                Net Link States (Area 0.0.0.2)

Display a routing table by using "show route" command.

OSPF> show route
============ OSPF network routing table ============
N IA 1.1.1.1/32            [3] area: 0.0.0.1
                           via 192.168.15.1, eth0
N IA 1.1.1.2/32            [2] area: 0.0.0.1
                           via 192.168.15.1, eth0
N    4.7.8.0/24            [2] area: 0.0.0.1
                           via 192.168.15.1, eth0
N IA 9.1.1.0/24            [12] area: 0.0.0.1
                           via 192.168.15.1, eth0
N IA 192.168.0.0/24        [3] area: 0.0.0.1
                           via 192.168.15.1, eth0
N    192.168.15.0/24       [1] area: 0.0.0.1
                           directly attached to eth0
N IA 192.168.80.0/24       [12] area: 0.0.0.1
                           via 192.168.15.1, eth0
N    192.168.151.0/24      [1] area: 0.0.0.1
                           directly attached to eth0
N IA 192.168.152.0/24      [2] area: 0.0.0.1
                           via 192.168.151.10, eth0
N IA 195.38.45.64/26       [2] area: 0.0.0.1
                           via 192.168.15.1, eth0
============ OSPF router routing table =============
R    192.168.151.10        [1] area: 0.0.0.1, ABR, ASBR
                           via 192.168.151.10, eth0
R    195.38.45.107         [1] area: 0.0.0.1, ABR
                           via 192.168.15.1, eth0


============ OSPF external routing table ===========
N E2 192.168.200.0/24      [1/7] tag: 0
                           via 192.168.151.10, eth0

The table consists of following data:

• OSPF network routing table –  includes a list of acquired routers for all accessible networks (or aggregated area ranges) of OSPF system. "IA" flag means that route destination is in the area to which the router is not connected, i.e. it’s an inter-area path. In square brackets a summary metric for all links through which a path lies to this network is specified. "via" prefix defines a router-gateway, i.e. the first router on the way to the destination (next hop).
• OSPF router routing table.
• OSPF external routing table. "E" flag points to the external link metric type (E1 – metric type 1, E2 – metric type 2). External link metric is printed in the "<metric of the router which advertised the link>/<link metric>" format.

In the following configuration, the router advertises external links created from the system routing table "connected" routes with metric type 2. If a destination for this route is a "192.168.103.37/24" subnetwork, the formed link will have metric 7, any other destination will not lead to external link’s advertising it.

OSPF(config)# access-list ANYNET permit any
OSPF(config)# access-list net200 permit 192.168.103.37/24
OSPF(config)# route-map MAP permit 10
OSPF(config-route-map)# match address net200
OSPF(config-route-map)# set metric 7
OSPF(config-route-map)# route-map MAP deny 11
OSPF(config-route-map)# match address ANYNET
OSPF(config-route-map)# router
OSPF(config-router)# redistribute connected route-map MAP