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CCNP Route - OSPF part 4 Labs, FAQs and Memory Tables

References
For additional information, see these resources:
■ “OSPF: Frequently Asked Questions” - http://www.cisco.com/en/US/tech/tk365/technologies_q_and_a_item09186a0080094704.shtml
■ “OSPF Not-So-Stubby Area (NSSA)” - www.cisco.com/en/US/tech/tk365/technologies_tech_note09186a0080094a88.shtml
■ “OSPF Design Guide” - www.cisco.com/en/US/tech/tk365/technologies_white_paper09186a0080094e9e.shtml
■ “Designing Large-Scale IP Internetworks” - www.cisco.com/en/US/docs/internetworking/design/guide/nd2003.html
■ “Cisco IOS Software Releases 12.4 Mainline” - http://www.cisco.com/en/US/products/ps6350/tsd_products_support_series_home.html
Radia Perlman. Interconnections: Bridges, Routers, Switches, and Internetworking Protocols(2nd Edition), Addison-Wesley Professional (1999).
An excellent reference for understanding routing protocol sequence numbering and aging
OSPF Commands


Commands for verifying OSPF operation:
show ip protocols
show ip route
show ip route ospf

show ip ospf route  (some platforms)
show ip ospf
show ip ospf database
show ip ospf interface
show ip ospf interface br
show ip ospf neighbor
show ip ospf virtual-links

debug ip packet   ! disable cef before  debug ip packet !!!!!
debug ip ospf events
debug ip ospf adj  (auth)
debug ip ospf packet

Settings and filters
R6# sh ip proto
Routing Protocol is "ospf 1"
  Outgoing update filter list for all interfaces is not set
  Incoming update filter list for all interfaces is not set
  Router ID 6.6.6.6
  Number of areas in this router is 2. 2 normal 0 stub 0 nssa
  Maximum path: 4
  Routing for Networks:
  Routing on Interfaces Configured Explicitly (Area 8):
    FastEthernet0/0
  Routing on Interfaces Configured Explicitly (Area 95):
    FastEthernet0/1
 Reference bandwidth unit is 100 mbps
  Routing Information Sources:
    Gateway         Distance      Last Update
    7.7.7.7              110      00:11:00
    4.4.4.4              110      00:11:00
  Distance: (default is 110)

Neighbors
 R6#sh ip ospf nei
Neighbor ID     Pri   State           Dead Time   Address         Interface
4.4.4.4           1   FULL/DROTHER    00:00:36    8.8.8.4         FastEthernet0/0
8.8.8.5           1   FULL/DR         00:00:35    8.8.8.5         FastEthernet0/0
21.21.21.21       1   FULL/BDR        00:00:37    172.21.21.21    FastEthernet0/1

Interfaces
R6# sh ip ospf int br
Interface    PID   Area            IP Address/Mask    Cost  State Nbrs F/C
Fa0/0        1     8               8.8.8.6/24         1     BDR   2/2
Fa0/1        1     95              172.21.21.6/24     1     DR    1/1

Topology

1) Easy way
R6#sh ip route ospf
O IA 192.168.12.0/24 [110/2] via 8.8.8.4, 00:14:28, FastEthernet0/0
O E2 192.168.208.0/24 [110/10] via 8.8.8.4, 00:14:28, FastEthernet0/0
     172.16.0.0/24 is subnetted, 1 subnets

R6#sh ip ospf route
            OSPF Router with ID (6.6.6.6) (Process ID 1)
    Area 8
    Intra-area Route List
*   8.8.8.0/24, Intra, cost 1, area 8, Connected
      via 8.8.8.6, FastEthernet0/0

    Intra-area Router Path List
i 4.4.4.4 [1] via 8.8.8.4, FastEthernet0/0, ABR, Area 8, SPF 2

    Inter-area Route List
*>  10.100.0.0/24, Inter, cost 3, area 8
      via 8.8.8.4, FastEthernet0/0
*>  10.120.0.0/24, Inter, cost 3, area 8
      via 8.8.8.4, FastEthernet0/0

2) Hard way


R6# sh ip ospf data | exc Checksum
            OSPF Router with ID (6.6.6.6) (Process ID 1)
                Router Link States (Area 8)
4.4.4.4         4.4.4.4         974         0x80000002 0x0008CF 1
6.6.6.6         6.6.6.6         954         0x80000002 0x00883E 1
8.8.8.5         8.8.8.5         975         0x80000002 0x0012AB 1

                Net Link States (Area 8)
8.8.8.5         8.8.8.5         955         0x80000002 0x00BCF8

                Summary Net Link States (Area 8)
10.100.0.0      4.4.4.4         960         0x80000001 0x00EDCE
10.120.0.0      4.4.4.4         960         0x80000001 0x00FCAB

R6# sh ip ospf database summary | inc Mask|State|Summary
                Summary Net Link States (Area 8)
  LS Type: Summary Links(Network)
  Link State ID: 10.100.0.0 (summary Network Number)
  Network Mask: /24
  LS Type: Summary Links(Network)
  Link State ID: 10.120.0.0 (summary Network Number)
  Network Mask: /24
  LS Type: Summary Links(Network)


R6# sh ip ospf database extern | inc Mask|State|Summary
                Type-5 AS External Link States
  Link State ID: 192.168.0.0 (External Network Number )
  Network Mask: /16
  Link State ID: 192.168.50.0 (External Network Number )
  Network Mask: /24
  Link State ID: 192.168.200.0 (External Network Number )
  Network Mask: /24




FAQs

Typical Reasons for OSPF Neighbor Problems link
 
Reason for Neighbor Adjacency Problem Commands for Diagnosing the Problem
OSPF is not configured on one of the routers. show ip ospf
OSPF is not enabled on an interface where it is needed. show ip ospf interface
OSPF HELLO or Dead timer interval values are mismatched. show ip ospf interface
ip ospf network-type mismatch on the adjoining interfaces. show ip ospf interface
MTU mismatch between neighboring interfaces. show interface <int-type><int-num>
OSPF area-type is stub on one neighbor, but the adjoining neighbor in the same area is not configured for stub. show running-config show ip ospf interface
OSPF neighbors have duplicate Router IDs. show ip ospf show ip ospf interface
OSPF is configured on the secondary network of the neighbor, but not on the primary network. This is an illegal configuration which prevents OSPF from being enabled on the interface. show ip ospf interface show running-config
OSPF HELLOs are not not processed due to a lack of resources, such as high CPU utilization or not enough memory. show memory summary show memory processor
An underlying Layer problem is preventing OSPF HELLOs from being received. show interface

Note: In order to aviod the MTU check while you establish ospf adjacency, you possibly need to configure the ip ospf mtu-ignore command in interface configuration mode.

OSPF DESIGN GUIDE
http://nobbyville.com/OSPF/OSPF2.html

OSPF: Frequently Asked Questions
http://nobbyville.com/OSPF/OSPF6.html

OSPF: Frequently Asked Questions (@ cisco.com)
http://www.cisco.com/en/US/tech/tk365/technologies_q_and_a_item09186a0080094704.shtml 

LSA Type 4
http://packetlife.net/blog/2008/apr/21/where-are-type-4-lsas-generated/


http://aconaway.com/2010/06/20/route-notes-ospf-filtering-and-summarization/


Memory Tables
- OSPF Point to Multipoint Non Broadcast over Frame Relay   (backup link - topology and pdf)
- OSPF Point to Multipoint Non Broadcast over Frame Relay   (backup link - topology and pdf) 


http://simplecisco.wordpress.com/tag/ccnp-route/

Commands
Show routes in OSPF domain
R12#  sh ip ospf data summary | inc State|Mask
                Summary Net Link States (Area 0)
  Link State ID: 1.1.0.0 (summary Network Number)
  Network Mask: /16
  Link State ID: 8.8.8.0 (summary Network Number)
  Network Mask: /24
  Link State ID: 10.100.0.0 (summary Network Number)
  Network Mask: /24
  Link State ID: 10.120.0.0 (summary Network Number)
  Network Mask: /24
  Link State ID: 10.130.0.0 (summary Network Number)
  Network Mask: /24
  Link State ID: 10.200.0.0 (summary Network Number)
  Network Mask: /24
  Link State ID: 192.168.23.0 (summary Network Number)
  Network Mask: /24
R12#  sh ip ospf data external | inc State|Mask
                Type-5 AS External Link States
  Link State ID: 192.168.0.0 (External Network Number )
  Network Mask: /16
  Link State ID: 192.168.50.0 (External Network Number )
  Network Mask: /24
  Link State ID: 192.168.200.0 (External Network Number )
  Network Mask: /24
  Link State ID: 192.168.205.0 (External Network Number )
  Network Mask: /24
  Link State ID: 192.168.208.0 (External Network Number )
  Network Mask: /24


R4#sh ip route ospf
     1.0.0.0/16 is subnetted, 1 subnets
O IA    1.1.0.0 [110/2001] via 192.168.12.1, 00:11:44, FastEthernet0/0
O E2 192.168.208.0/24 [110/10] via 192.168.12.7, 1d06h, FastEthernet0/0
     172.16.0.0/24 is subnetted, 1 subnets
O       172.16.1.0 [110/2] via 192.168.12.1, 2d22h, FastEthernet0/0
O E2 192.168.200.0/24 [110/10] via 192.168.12.7, 1d06h, FastEthernet0/0
     10.0.0.0/24 is subnetted, 4 subnets
O IA    10.100.0.0 [110/2] via 192.168.12.7, 1d06h, FastEthernet0/0
O IA    10.120.0.0 [110/2] via 192.168.12.7, 1d06h, FastEthernet0/0
O IA    10.130.0.0 [110/2] via 192.168.12.7, 1d06h, FastEthernet0/0
O IA    10.200.0.0 [110/2] via 192.168.12.7, 1d06h, FastEthernet0/0
O IA 192.168.23.0/24 [110/3] via 192.168.12.1, 2d22h, FastEthernet0/0
O E2 192.168.205.0/24 [110/10] via 192.168.12.7, 1d06h, FastEthernet0/0
O E2 192.168.50.0/24 [110/10] via 192.168.12.7, 1d06h, FastEthernet0/0
O E2 192.168.0.0/16 [110/5] via 192.168.12.7, 1d06h, FastEthernet0/0
R4#



Labs
- OSPF Point to Multipoint Non Broadcast over Frame Relay   (backup link - topology and pdf)
- OSPF Point to Multipoint Non Broadcast over Frame Relay   (backup link - topology and pdf) 


http://simplecisco.wordpress.com/tag/ccnp-route/ 


 GNS3 Labs Files https://db.tt/ZPxAqtmo