OSPF Basic Configuration on Cisco ================================= Details on how to do the initial ospf configuration followed by actual configuration commands for each router. Special case for dexter since we also do the redistribution of default route The 6 routers are divided into 2 areas. Dexter, Radia, and Mrhorse are in area 0, with Radia and Mrhorse being the ABRs between area 0 and area 1. Radia, Mrhorse, Tony, Yakov, and Big-baby are set up in area 1. Router's used in the setup Dexter Radia Mrhorse Tony Yakov Big-baby 1. Basic Setup Disable RIP (if enabled) on the routers using no router rip Enable OSPF routing router ospf process-id Define an interface and the area ID network address wildcard-mask area area-id Dexter ====== router ospf 100 network 131.252.215.4 0.0.0.0 area 0 network 131.252.215.33 0.0.0.0 area 0 Radia ====== router ospf 100 network 131.252.215.34 0.0.0.0 area 0 network 131.252.215.49 0.0.0.0 area 1 Mrhorse ======== router ospf 100 network 131.252.215.35 0.0.0.0 area 0 network 131.252.215.67 0.0.0.0 area 1 Tony ===== router ospf 100 network 131.252.215.50 0.0.0.0 area 1 network 131.252.215.65 0.0.0.0 area 1 Yakov ====== router ospf 100 network 131.252.215.66 0.0.0.0 area 1 network 131.252.215.81 0.0.0.0 area 1 Big-baby ========= router ospf 100 network 131.252.215.82 0.0.0.0 area 1 2. All static routes are removed from all six routers except the default route on Dexter. no ip route network [mask] {address | interface} [distance] For example: Dexter ====== no ip route 131.252.215.48 255.255.255.240 131.252.215.34 no ip route 131.252.215.64 255.255.255.240 131.252.215.34 no ip route 131.252.215.80 255.255.255.240 131.252.215.34 Mrhorse ======= no ip route 0.0.0.0 0.0.0.0 131.252.215.33 3. The default route on Dexter are redistributed to the other routers. To force the autonomous system boundary router to generate a default route, use the following command in router configuration mode: default-information originate [always] [metric metric-value] [metric-type type-value] [route-map map-name] Dexter (in router config mode) =========================== default-information originate metric-type 1 /******************************************************************************************/ /******************************************************************************************/ /******************************************************************************************/ show running-config =================== To display the current router configuration, enter the following command: show run /******************************************************************************************/ Dexter ====== dexter#show run Building configuration... Current configuration: ! ! Last configuration change at 13:58:38 PS Tue Feb 6 2001 ! version 12.1 service timestamps debug uptime service timestamps log uptime service password-encryption ! hostname dexter ! boot system flash c2600-jk2s-mz.121-1.T.bin enable secret 5 $1$Vj/C$GLaYn2mecQGihv22oswee0 ! ! memory-size iomem 10 clock timezone PS -8 clock summer-time PDT recurring ip subnet-zero ip domain-list . ip domain-name cs.pdx.edu ip name-server 131.252.208.38 ip name-server 131.252.208.58 ! cns event-service server ! ! interface FastEthernet0/0 description dexter/port0 ip address 131.252.215.4 255.255.255.224 duplex auto speed auto ! interface FastEthernet0/1 description dexter/port1 ip address 131.252.215.33 255.255.255.240 duplex auto speed auto ! router ospf 100 network 131.252.215.4 0.0.0.0 area 0 network 131.252.215.33 0.0.0.0 area 0 default-information originate metric-type 1 ! ip classless ip route 0.0.0.0 0.0.0.0 131.252.215.1 no ip http server ! route-map blockdefault deny 1 match ip address 1 ! route-map blockdefault permit 2 match ip address 2 ! ! snmp-server engineID local 0000000902000050548FB360 snmp-server community public RO snmp-server location FAB-100-17 snmp-server contact davburns@ee.pdx.edu snmp-server enable traps snmp snmp-server enable traps isdn call-information snmp-server enable traps isdn layer2 snmp-server enable traps config snmp-server enable traps entity snmp-server enable traps envmon snmp-server enable traps bgp snmp-server enable traps rsvp snmp-server enable traps frame-relay snmp-server enable traps syslog snmp-server enable traps rtr snmp-server host 131.252.215.5 public ! line con 0 transport preferred none transport input none line aux 0 line vty 0 4 password 7 050D0A0E335C0E3A17550D080709 login transport preferred none ! ntp clock-period 17180187 ntp server 131.252.215.1 no scheduler allocate end Radia ====== radia#show run Building configuration... Current configuration: ! version 12.0 service timestamps debug uptime service timestamps log uptime service password-encryption ! hostname radia ! boot system flash:c2600-js56i-mz.120-2.XC2.bin enable secret 5 $1$Z7.g$B/4/2xPH9ZmblcRCqFzIW1 ! ip subnet-zero ip domain-name cs.pdx.edu ip name-server 131.252.208.38 ip name-server 131.252.208.58 ! ! interface FastEthernet0/0 description radia/port0 ip address 131.252.215.34 255.255.255.240 no ip directed-broadcast ! interface FastEthernet0/1 description radia/port1 ip address 131.252.215.49 255.255.255.240 no ip directed-broadcast ! router ospf 100 network 131.252.215.34 0.0.0.0 area 0 network 131.252.215.49 0.0.0.0 area 1 ! ip classless no ip http server ! access-list 101 permit ip any any ! snmp-server community public RO snmp-server location FAB-100-17 snmp-server contact jrb@cs.pdx.edu snmp-server enable traps snmp snmp-server enable traps isdn call-information snmp-server enable traps config snmp-server enable traps entity snmp-server enable traps envmon snmp-server enable traps bgp snmp-server enable traps rsvp snmp-server enable traps frame-relay snmp-server enable traps syslog snmp-server enable traps rtr snmp-server host 131.252.215.5 traps public ! line con 0 transport preferred none transport input none line aux 0 line vty 0 4 password 7 094A42080B155721055C1E302721 login transport preferred none ! no scheduler allocate end Mrhorse ======== mrhorse#show run Building configuration... Current configuration: ! ! Last configuration change at 10:35:24 PST Fri Feb 2 2001 ! version 12.0 service timestamps debug uptime service timestamps log uptime service password-encryption service udp-small-servers service tcp-small-servers ! hostname mrhorse ! enable secret 5 $1$jYHf$QZp0D/zXCtuxdgIknsu2K1 ! ip subnet-zero no ip finger ip domain-list cs.pdx.edu ip domain-list cat.pdx.edu ip domain-list ee.pdx.edu ip domain-list pdx.edu ip domain-list . ip name-server 131.252.208.38 clock timezone PST -8 clock summer-time PDT recurring ! ! ! interface Ethernet0 description Connected to minshall, port #7 ip address 131.252.215.35 255.255.255.240 no ip directed-broadcast ! interface Ethernet1 description Connected to minshall, port #15 ip address 131.252.215.67 255.255.255.240 no ip directed-broadcast ! interface Serial0 no ip address no ip directed-broadcast shutdown no fair-queue ! interface Serial1 no ip address no ip directed-broadcast shutdown ! router ospf 100 network 131.252.215.35 0.0.0.0 area 0 network 131.252.215.67 0.0.0.0 area 1 ! ip classless ! logging 131.252.215.5 access-list 1 permit 131.252.215.5 access-list 99 deny any snmp-server community public RO 1 snmp-server enable traps snmp snmp-server enable traps isdn call-information snmp-server enable traps config snmp-server enable traps entity snmp-server enable traps bgp snmp-server enable traps frame-relay snmp-server enable traps rtr snmp-server host 131.252.215.5 traps public ! line con 0 exec-timeout 0 0 transport preferred none transport input none line aux 0 exec-timeout 0 0 transport preferred none line vty 0 4 exec-timeout 0 0 password 7 104805181707523802543031282D login transport preferred none ! ntp clock-period 17180120 ntp server 131.252.120.25 ntp server 131.252.208.58 ntp server 131.252.209.59 ntp server 131.252.120.40 ntp server 131.252.208.38 ntp server 131.252.217.1 ntp server 131.252.221.65 end Tony ===== tony#show run Building configuration... Current configuration: ! version 12.0 service timestamps debug uptime service timestamps log uptime service password-encryption ! hostname tony ! boot system flash:c2600-js56i-mz.120-2.XC2.bin enable secret 5 $1$fLjf$MJlI08QuUrx1.P/b5hO3W0 ! ip subnet-zero ip domain-name cs.pdx.edu ip name-server 131.252.208.38 ip name-server 131.252.208.58 ! ! ! ! ! interface FastEthernet0/0 description tony/port0 ip address 131.252.215.50 255.255.255.240 no ip directed-broadcast ! interface FastEthernet0/1 description tony/port1 ip address 131.252.215.65 255.255.255.240 no ip directed-broadcast ! router ospf 100 network 131.252.215.50 0.0.0.0 area 1 network 131.252.215.65 0.0.0.0 area 1 ! ip classless no ip http server ! access-list 30 deny any ! snmp-server community public RO snmp-server location FAB-100-17 snmp-server contact jrb@cs.pdx.edu snmp-server enable traps snmp snmp-server enable traps isdn call-information snmp-server enable traps config snmp-server enable traps entity snmp-server enable traps envmon snmp-server enable traps bgp snmp-server enable traps rsvp snmp-server enable traps frame-relay snmp-server enable traps syslog snmp-server enable traps rtr snmp-server host 131.252.215.5 traps public ! line con 0 transport preferred none transport input none line aux 0 line vty 0 4 password 7 104805181707523802543031282D login transport preferred none ! no scheduler allocate end Yakov ====== yakov#show run Building configuration... Current configuration: ! version 12.0 service timestamps debug uptime service timestamps log uptime service password-encryption ! hostname yakov ! boot system flash:c2600-js56i-mz.120-2.XC2.bin enable secret 5 $1$08DB$4EnWhf4HXUI2RbyeJAh3j/ ! ip subnet-zero ip domain-name cs.pdx.edu ip name-server 131.252.208.38 ip name-server 131.252.208.58 ! ! interface FastEthernet0/0 description yakov/port0 ip address 131.252.215.66 255.255.255.240 no ip directed-broadcast ! interface FastEthernet0/1 description yakov/port1 ip address 131.252.215.81 255.255.255.240 no ip directed-broadcast ! router ospf 100 network 131.252.215.66 0.0.0.0 area 1 network 131.252.215.81 0.0.0.0 area 1 ! ip classless no ip http server ! ! snmp-server community public RO snmp-server location FAB-100-17 snmp-server contact jrb@cs.pdx.edu snmp-server enable traps snmp snmp-server enable traps isdn call-information snmp-server enable traps config snmp-server enable traps entity snmp-server enable traps envmon snmp-server enable traps bgp snmp-server enable traps rsvp snmp-server enable traps frame-relay snmp-server enable traps syslog snmp-server enable traps rtr snmp-server host 131.252.215.5 traps public ! line con 0 transport preferred none transport input none line aux 0 line vty 0 4 password 7 0200085A19164F12421E13030912 login transport preferred none ! no scheduler allocate end Big-baby ======== big-baby#show run Building configuration... Current configuration: ! version 11.0 service password-encryption service udp-small-servers service tcp-small-servers ! hostname big-baby ! boot system flash /cisco/images/11.0/gs7-k-mz.110-7.1 enable secret 5 $1$dSK8$JDzrXHENa3o819KeNKaDq1 ! ip subnet-zero ! interface Ethernet0/0 description big-baby/port0 ip address 131.252.215.82 255.255.255.240 no ip directed-broadcast ! interface Ethernet0/1 description big-baby/port1 no ip address shutdown ! interface Ethernet0/2 description big-baby/port2 no ip address shutdown ! interface Ethernet0/3 description big-baby/port3 no ip address shutdown ! interface Ethernet0/4 description big-baby/port4 no ip address shutdown ! interface Ethernet0/5 description big-baby/port5 no ip address shutdown ! interface ATM1/0 description big-baby/ATM/port0 no ip address shutdown ! router ospf 100 network 131.252.215.82 0.0.0.0 area 1 ! ip domain-name cs.pdx.edu ip name-server 131.252.208.38 ip name-server 131.252.208.58 ip classless ! snmp-server community public RO snmp-server location pcat144 snmp-server contact jrb@cs.pdx.edu snmp-server enable traps isdn snmp-server enable traps envmon snmp-server enable traps bgp snmp-server enable traps frame-relay snmp-server host 131.252.215.5 traps ! line con 0 exec-timeout 0 0 transport preferred none line aux 0 transport input all line vty 0 4 password 7 14111E0A1E146A182A78292F login transport preferred none ! end /******************************************************************************************/ /******************************************************************************************/ /******************************************************************************************/ show ip route ============= To display the current state of the routing table. show ip route [address [mask] [longer-prefixes]] | [protocol [process-id]] Syntax Description address (Optional) Address about which routing information should be displayed. mask (Optional) Argument for a subnet mask. longer-prefixes (Optional) The address and mask pair becomes a prefix and any routes that match that prefix are displayed. protocol (Optional) Name of a routing protocol; or the keyword connected, static, or summary. If you specify a protocol, use one of the following keywords: bgp, egp, eigrp, hello, igrp, isis, ospf, or rip. process-id (Optional) Number used to identify a process of the specified protocol. /******************************************************************************************/ Dexter ====== dexter#show ip route Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2 E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area * - candidate default, U - per-user static route, o - ODR P - periodic downloaded static route Gateway of last resort is 131.252.215.1 to network 0.0.0.0 131.252.0.0/16 is variably subnetted, 5 subnets, 2 masks C 131.252.215.32/28 is directly connected, FastEthernet0/1 O IA 131.252.215.48/28 [110/2] via 131.252.215.34, 00:09:12, FastEthernet0/1 C 131.252.215.0/27 is directly connected, FastEthernet0/0 O IA 131.252.215.64/28 [110/3] via 131.252.215.34, 00:09:12, FastEthernet0/1 O IA 131.252.215.80/28 [110/4] via 131.252.215.34, 00:09:12, FastEthernet0/1 S* 0.0.0.0/0 [1/0] via 131.252.215.1 Radia ===== radia#show ip route Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2 E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, * - candidate default U - per-user static route, o - ODR T - traffic engineered route Gateway of last resort is 131.252.215.33 to network 0.0.0.0 131.252.0.0/16 is variably subnetted, 5 subnets, 2 masks C 131.252.215.32/28 is directly connected, FastEthernet0/0 C 131.252.215.48/28 is directly connected, FastEthernet0/1 O 131.252.215.0/27 [110/2] via 131.252.215.33, FastEthernet0/0 O 131.252.215.64/28 [110/2] via 131.252.215.50, FastEthernet0/1 O 131.252.215.80/28 [110/3] via 131.252.215.50, FastEthernet0/1 O*E1 0.0.0.0/0 [110/2] via 131.252.215.33, FastEthernet0/0 Mrhorse ======== mrhorse#show ip route Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2 E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, * - candidate default U - per-user static route, o - ODR Gateway of last resort is 131.252.215.33 to network 0.0.0.0 131.252.0.0/16 is variably subnetted, 5 subnets, 2 masks C 131.252.215.32/28 is directly connected, Ethernet0 O 131.252.215.48/28 [110/11] via 131.252.215.65, 00:25:21, Ethernet1 O 131.252.215.0/27 [110/11] via 131.252.215.33, 00:21:36, Ethernet0 C 131.252.215.64/28 is directly connected, Ethernet1 O 131.252.215.80/28 [110/11] via 131.252.215.66, 00:25:21, Ethernet1 O*E1 0.0.0.0/0 [110/11] via 131.252.215.33, 00:21:26, Ethernet0 Tony ===== tony#show ip route Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2 E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, * - candidate default U - per-user static route, o - ODR T - traffic engineered route Gateway of last resort is 131.252.215.49 to network 0.0.0.0 131.252.0.0/16 is variably subnetted, 5 subnets, 2 masks O IA 131.252.215.32/28 [110/2] via 131.252.215.49, FastEthernet0/0 C 131.252.215.48/28 is directly connected, FastEthernet0/0 O IA 131.252.215.0/27 [110/3] via 131.252.215.49, FastEthernet0/0 C 131.252.215.64/28 is directly connected, FastEthernet0/1 O 131.252.215.80/28 [110/2] via 131.252.215.66, FastEthernet0/1 O*E1 0.0.0.0/0 [110/3] via 131.252.215.49, FastEthernet0/0 Yakov ====== yakov#show ip route Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2 E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, * - candidate default U - per-user static route, o - ODR T - traffic engineered route Gateway of last resort is 131.252.215.65 to network 0.0.0.0 131.252.0.0/16 is variably subnetted, 5 subnets, 2 masks O IA 131.252.215.32/28 [110/3] via 131.252.215.65, FastEthernet0/0 O 131.252.215.48/28 [110/2] via 131.252.215.65, FastEthernet0/0 O IA 131.252.215.0/27 [110/4] via 131.252.215.65, FastEthernet0/0 C 131.252.215.64/28 is directly connected, FastEthernet0/0 C 131.252.215.80/28 is directly connected, FastEthernet0/1 O*E1 0.0.0.0/0 [110/4] via 131.252.215.65, FastEthernet0/0 Big-baby ========= big-baby#show ip route Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, * - candidate default Gateway of last resort is 131.252.215.81 to network 0.0.0.0 131.252.0.0 is variably subnetted, 5 subnets, 2 masks O IA 131.252.215.32 255.255.255.240 [110/13] via 131.252.215.81, 00:27:51, Ethernet0/0 O 131.252.215.48 255.255.255.240 [110/12] via 131.252.215.81, 00:31:40, Ethernet0/0 O IA 131.252.215.0 255.255.255.224 [110/14] via 131.252.215.81, 00:27:52, Ethernet0/0 O 131.252.215.64 255.255.255.240 [110/11] via 131.252.215.81, 00:31:40, Ethernet0/0 C 131.252.215.80 255.255.255.240 is directly connected, Ethernet0/0 O*E1 0.0.0.0 0.0.0.0 [110/14] via 131.252.215.81, 00:27:52, Ethernet0/0 /******************************************************************************/ /******************************************************************************/ /******************************************************************************/ show ip ospf ============ show ip ospf [process-id] This command displays general information about the ospf processes. In case there are more than one ospf processes running on a router, we can specify the process-id (optional) to see details only for a particular process. The details of the output fields are as follows: Routing Process x with ID y - Process ID and OSPF router ID Supports.... - Number of Types of service supported It is... - Possible types are internal router, ABR, ASBR Summary Link update Interval - Specify summary update interval in hours:minutes:seconds, and time to next update. External Link update interval - Specify external update interval in hours:minutes:seconds, and time to next update. Redistributing External Routes from - Lists of redistributed routes, by protocol Number of areas - Number of areas in router, area addresses, and so on Link State update Interval - Specify router and network link state update interval in hours:minutes:seconds, and time to next update Link State Age Interval - Specify max-aged update deletion interval and time until next database cleanup in hours:minutes:seconds /******************************************************************************/ DEXTER: ======= dexter#show ip ospf Routing Process "ospf 100" with ID 131.252.215.33 Supports only single TOS(TOS0) routes Supports opaque LSA It is an autonomous system boundary router Redistributing External Routes from, SPF schedule delay 5 secs, Hold time between two SPFs 10 secs Minimum LSA interval 5 secs. Minimum LSA arrival 1 secs Number of external LSA 1. Checksum Sum 0x7FD6 Number of opaque AS LSA 0. Checksum Sum 0x0 Number of DCbitless external and opaque AS LSA 0 Number of DoNotAge external and opaque AS LSA 0 Number of areas in this router is 1. 1 normal 0 stub 0 nssa External flood list length 0 Area BACKBONE(0) Number of interfaces in this area is 2 Area has no authentication SPF algorithm executed 5 times Area ranges are Number of LSA 11. Checksum Sum 0x7A84F Number of opaque link LSA 0. Checksum Sum 0x0 Number of DCbitless LSA 1 Number of indication LSA 1 Number of DoNotAge LSA 0 --More-- ^H^H^H^H^H^H^H^H^H ^H^H^H^H^H^H^H^H^H Flood list length 0 RADIA: ====== radia#show ip ospf Routing Process "ospf 100" with ID 131.252.215.49 Supports only single TOS(TOS0) routes It is an area border router SPF schedule delay 5 secs, Hold time between two SPFs 10 secs Minimum LSA interval 5 secs. Minimum LSA arrival 1 secs Number of external LSA 1. Checksum Sum 0x7FD6 Number of DCbitless external LSA 0 Number of DoNotAge external LSA 0 Number of areas in this router is 2. 2 normal 0 stub 0 nssa External flood list length 0 Area BACKBONE(0) Number of interfaces in this area is 1 Area has no authentication SPF algorithm executed 6 times Area ranges are Number of LSA 11. Checksum Sum 0x7A84F Number of DCbitless LSA 1 Number of indication LSA 1 Number of DoNotAge LSA 0 Flood list length 0 Area 1 Number of interfaces in this area is 1 Area has no authentication --More-- ^H^H^H^H^H^H^H^H^H ^H^H^H^H^H^H^H^H^H SPF algorithm executed 3 times Area ranges are Number of LSA 15. Checksum Sum 0x70FA4 Number of DCbitless LSA 3 Number of indication LSA 1 Number of DoNotAge LSA 0 Flood list length 0 TONY: ===== tony#show ip ospf Routing Process "ospf 100" with ID 131.252.215.65 Supports only single TOS(TOS0) routes SPF schedule delay 5 secs, Hold time between two SPFs 10 secs Minimum LSA interval 5 secs. Minimum LSA arrival 1 secs Number of external LSA 1. Checksum Sum 0x7FD6 Number of DCbitless external LSA 0 Number of DoNotAge external LSA 0 Number of areas in this router is 1. 1 normal 0 stub 0 nssa External flood list length 0 Area 1 Number of interfaces in this area is 2 Area has no authentication SPF algorithm executed 6 times Area ranges are Number of LSA 15. Checksum Sum 0x70BA6 Number of DCbitless LSA 3 Number of indication LSA 1 Number of DoNotAge LSA 0 Flood list length 0 MRHORSE: ======== mrhorse#show ip ospf Routing Process "ospf 100" with ID 131.252.215.67 Supports only single TOS(TOS0) routes It is an area border router SPF schedule delay 5 secs, Hold time between two SPFs 10 secs Minimum LSA interval 5 secs. Minimum LSA arrival 1 secs Number of external LSA 1. Checksum Sum 0x7FD6 Number of DCbitless external LSA 0 Number of DoNotAge external LSA 0 Number of areas in this router is 2. 2 normal 0 stub 0 nssa Area BACKBONE(0) Number of interfaces in this area is 1 Area has no authentication SPF algorithm executed 12 times Area ranges are Number of LSA 11. Checksum Sum 0x7A84F Number of DCbitless LSA 1 Number of indication LSA 1 Number of DoNotAge LSA 0 Area 1 Number of interfaces in this area is 1 Area has no authentication SPF algorithm executed 17 times Area ranges are --More-- ^H^H^H^H^H^H^H^H^H ^H^H^H^H^H^H^H^H^H Number of LSA 15. Checksum Sum 0x70BA6 --More-- ^H^H^H^H^H^H^H^H^H ^H^H^H^H^H^H^H^H^H Number of DCbitless LSA 3 Number of indication LSA 1 Number of DoNotAge LSA 0 YAKOV: ====== yakov#show ip ospf Routing Process "ospf 100" with ID 131.252.215.81 Supports only single TOS(TOS0) routes SPF schedule delay 5 secs, Hold time between two SPFs 10 secs Minimum LSA interval 5 secs. Minimum LSA arrival 1 secs Number of external LSA 1. Checksum Sum 0x7FD6 Number of DCbitless external LSA 0 Number of DoNotAge external LSA 0 Number of areas in this router is 1. 1 normal 0 stub 0 nssa External flood list length 0 Area 1 Number of interfaces in this area is 2 Area has no authentication SPF algorithm executed 7 times Area ranges are Number of LSA 15. Checksum Sum 0x705A9 Number of DCbitless LSA 3 Number of indication LSA 1 Number of DoNotAge LSA 0 Flood list length 0 BIG-BABY: ========= big-baby#show ip ospf Routing Process "ospf 100" with ID 131.252.215.82 Supports only single TOS(TOS0) routes SPF schedule delay 5 secs, Hold time between two SPFs 10 secs Number of areas in this router is 1. 1 normal 0 stub Area 1 Number of interfaces in this area is 1 Area has no authentication SPF algorithm executed 7 times Area ranges are Link State Update Interval is 0:30:00 and due in 0:21:00 Link State Age Interval is 0:20:00 and due in 0:01:00 /******************************************************************************/ /******************************************************************************/ /******************************************************************************/ show ip ospf interface ====================== show ip ospf interface [type number] This command shows the ospf interface related information. This can be obtained either for all the interfaces or by specifying the type a nd number of the interface for which the information is required in the optional fields. The details of the output of this command are: Ethernet- Status of physical link and operational status of protocol Internet Address - Interface IP address, subnet mask, and area address AS - Autonomous system number (OSPF process ID), router ID, network type, link state cost Transmit Delay - Transmit delay, interface state, and router priority Designated Router - Designated router ID and respective interface IP address Backup Designated Router - Backup designated router ID and respective interface IP address Timer Intervals configured - Configuration of timer intervals Hello - Number of seconds until next hello packet is sent out this interface. Neighbor Count - Count of network neighbors and list of adjacent neighbors /******************************************************************************/ DEXTER: ======= dexter#show ip ospf interface FastEthernet0/0 is up, line protocol is up Internet Address 131.252.215.4/27, Area 0 Process ID 100, Router ID 131.252.215.33, Network Type BROADCAST, Cost: 1 Transmit Delay is 1 sec, State DR, Priority 1 Designated Router (ID) 131.252.215.33, Interface address 131.252.215.4 No backup designated router on this network Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5 Hello due in 00:00:08 Index 1/1, flood queue length 0 Next 0x0(0)/0x0(0) Last flood scan length is 0, maximum is 0 Last flood scan time is 0 msec, maximum is 0 msec Neighbor Count is 0, Adjacent neighbor count is 0 Suppress hello for 0 neighbor(s) --More-- ^H^H^H^H^H^H^H^H^H ^H^H^H^H^H^H^H^H^HFastEthernet0/1 is up, line protocol is up Internet Address 131.252.215.33/28, Area 0 Process ID 100, Router ID 131.252.215.33, Network Type BROADCAST, Cost: 1 Transmit Delay is 1 sec, State DROTHER, Priority 1 Designated Router (ID) 131.252.215.67, Interface address 131.252.215.35 Backup Designated router (ID) 131.252.215.49, Interface address 131.252.215.34 Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5 Hello due in 00:00:02 Index 2/2, flood queue length 0 Next 0x0(0)/0x0(0) Last flood scan length is 1, maximum is 1 Last flood scan time is 0 msec, maximum is 0 msec Neighbor Count is 2, Adjacent neighbor count is 2 Adjacent with neighbor 131.252.215.67 (Designated Router) Adjacent with neighbor 131.252.215.49 (Backup Designated Router) Suppress hello for 0 neighbor(s) RADIA: ====== radia#show ip ospf interface FastEthernet0/0 is up, line protocol is up Internet Address 131.252.215.34/28, Area 0 Process ID 100, Router ID 131.252.215.49, Network Type BROADCAST, Cost: 1 Transmit Delay is 1 sec, State BDR, Priority 1 Designated Router (ID) 131.252.215.67, Interface address 131.252.215.35 Backup Designated router (ID) 131.252.215.49, Interface address 131.252.215.34 Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5 Hello due in 00:00:02 Index 1/1, flood queue length 0 Next 0x0(0)/0x0(0) Last flood scan length is 0, maximum is 2 Last flood scan time is 0 msec, maximum is 0 msec Neighbor Count is 2, Adjacent neighbor count is 2 Adjacent with neighbor 131.252.215.33 Adjacent with neighbor 131.252.215.67 (Designated Router) Suppress hello for 0 neighbor(s) --More-- ^H^H^H^H^H^H^H^H^H ^H^H^H^H^H^H^H^H^HFastEthernet0/1 is up, line protocol is up Internet Address 131.252.215.49/28, Area 1 Process ID 100, Router ID 131.252.215.49, Network Type BROADCAST, Cost: 1 Transmit Delay is 1 sec, State BDR, Priority 1 Designated Router (ID) 131.252.215.65, Interface address 131.252.215.50 Backup Designated router (ID) 131.252.215.49, Interface address 131.252.215.49 Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5 Hello due in 00:00:07 Index 1/2, flood queue length 0 Next 0x0(0)/0x0(0) Last flood scan length is 1, maximum is 2 Last flood scan time is 0 msec, maximum is 0 msec Neighbor Count is 1, Adjacent neighbor count is 1 Adjacent with neighbor 131.252.215.65 (Designated Router) Suppress hello for 0 neighbor(s) TONY: ===== tony#show ip ospf interface FastEthernet0/0 is up, line protocol is up Internet Address 131.252.215.50/28, Area 1 Process ID 100, Router ID 131.252.215.65, Network Type BROADCAST, Cost: 1 Transmit Delay is 1 sec, State DR, Priority 1 Designated Router (ID) 131.252.215.65, Interface address 131.252.215.50 Backup Designated router (ID) 131.252.215.49, Interface address 131.252.215.49 Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5 Hello due in 00:00:06 Index 1/1, flood queue length 0 Next 0x0(0)/0x0(0) Last flood scan length is 2, maximum is 2 Last flood scan time is 0 msec, maximum is 0 msec Neighbor Count is 1, Adjacent neighbor count is 1 Adjacent with neighbor 131.252.215.49 (Backup Designated Router) Suppress hello for 0 neighbor(s) --More-- ^H^H^H^H^H^H^H^H^H ^H^H^H^H^H^H^H^H^HFastEthernet0/1 is up, line protocol is up Internet Address 131.252.215.65/28, Area 1 Process ID 100, Router ID 131.252.215.65, Network Type BROADCAST, Cost: 1 Transmit Delay is 1 sec, State DROTHER, Priority 1 Designated Router (ID) 131.252.215.67, Interface address 131.252.215.67 Backup Designated router (ID) 131.252.215.81, Interface address 131.252.215.66 Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5 Hello due in 00:00:07 Index 2/2, flood queue length 0 Next 0x0(0)/0x0(0) Last flood scan length is 0, maximum is 3 Last flood scan time is 0 msec, maximum is 0 msec Neighbor Count is 2, Adjacent neighbor count is 2 Adjacent with neighbor 131.252.215.67 (Designated Router) Adjacent with neighbor 131.252.215.81 (Backup Designated Router) Suppress hello for 0 neighbor(s) MRHORSE: ======== mrhorse#show ip ospf interface Ethernet0 is up, line protocol is up Internet Address 131.252.215.35/28, Area 0 Process ID 100, Router ID 131.252.215.67, Network Type BROADCAST, Cost: 10 Transmit Delay is 1 sec, State DR, Priority 1 Designated Router (ID) 131.252.215.67, Interface address 131.252.215.35 Backup Designated router (ID) 131.252.215.49, Interface address 131.252.215.34 Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5 Hello due in 00:00:04 Neighbor Count is 2, Adjacent neighbor count is 2 Adjacent with neighbor 131.252.215.33 Adjacent with neighbor 131.252.215.49 (Backup Designated Router) Suppress hello for 0 neighbor(s) --More-- ^H^H^H^H^H^H^H^H^H ^H^H^H^H^H^H^H^H^HEthernet1 is up, line protocol is up Internet Address 131.252.215.67/28, Area 1 Process ID 100, Router ID 131.252.215.67, Network Type BROADCAST, Cost: 10 Transmit Delay is 1 sec, State DR, Priority 1 Designated Router (ID) 131.252.215.67, Interface address 131.252.215.67 Backup Designated router (ID) 131.252.215.81, Interface address 131.252.215.66 Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5 Hello due in 00:00:00 Neighbor Count is 2, Adjacent neighbor count is 2 Adjacent with neighbor 131.252.215.65 Adjacent with neighbor 131.252.215.81 (Backup Designated Router) Suppress hello for 0 neighbor(s) YAKOV: ====== yakov# show ip ospf interface FastEthernet0/0 is up, line protocol is up Internet Address 131.252.215.66/28, Area 1 Process ID 100, Router ID 131.252.215.81, Network Type BROADCAST, Cost: 1 Transmit Delay is 1 sec, State BDR, Priority 1 Designated Router (ID) 131.252.215.67, Interface address 131.252.215.67 Backup Designated router (ID) 131.252.215.81, Interface address 131.252.215.66 Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5 Hello due in 00:00:09 Index 1/1, flood queue length 0 Next 0x0(0)/0x0(0) Last flood scan length is 1, maximum is 2 Last flood scan time is 0 msec, maximum is 0 msec Neighbor Count is 2, Adjacent neighbor count is 2 Adjacent with neighbor 131.252.215.65 Adjacent with neighbor 131.252.215.67 (Designated Router) Suppress hello for 0 neighbor(s) --More-- ^H^H^H^H^H^H^H^H^H ^H^H^H^H^H^H^H^H^HFastEthernet0/1 is up, line protocol is up Internet Address 131.252.215.81/28, Area 1 Process ID 100, Router ID 131.252.215.81, Network Type BROADCAST, Cost: 1 Transmit Delay is 1 sec, State BDR, Priority 1 Designated Router (ID) 131.252.215.82, Interface address 131.252.215.82 Backup Designated router (ID) 131.252.215.81, Interface address 131.252.215.81 Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5 Hello due in 00:00:06 Index 2/2, flood queue length 0 Next 0x0(0)/0x0(0) Last flood scan length is 1, maximum is 3 Last flood scan time is 0 msec, maximum is 0 msec Neighbor Count is 1, Adjacent neighbor count is 1 Adjacent with neighbor 131.252.215.82 (Designated Router) Suppress hello for 0 neighbor(s) BIG-BABY: ========= big-baby#show ip ospf inter Ethernet0/0 is up, line protocol is up Internet Address 131.252.215.82 255.255.255.240, Area 1 Process ID 100, Router ID 131.252.215.82, Network Type BROADCAST, Cost: 10 Transmit Delay is 1 sec, State DR, Priority 1 Designated Router (ID) 131.252.215.82, Interface address 131.252.215.82 Backup Designated router (ID) 131.252.215.81, Interface address 131.252.215.81 Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5 Hello due in 0:00:04 Neighbor Count is 1, Adjacent neighbor count is 1 Adjacent with neighbor 131.252.215.81 (Backup Designated Router) --More-- ^H^H^H^H^H^H^H^H^H ^H^H^H^H^H^H^H^H^HEthernet0/1 is administratively down, line protocol is $ OSPF not enabled on this interface --More-- ^H^H^H^H^H^H^H^H^H ^H^H^H^H^H^H^H^H^HEthernet0/2 is administratively down, line protocol is $ --More-- ^H^H^H^H^H^H^H^H^H ^H^H^H^H^H^H^H^H^H OSPF not enabled on this interface --More-- ^H^H^H^H^H^H^H^H^H ^H^H^H^H^H^H^H^H^HEthernet0/3 is administratively down, line protocol is $ OSPF not enabled on this interface --More-- ^H^H^H^H^H^H^H^H^H ^H^H^H^H^H^H^H^H^HEthernet0/4 is administratively down, line protocol is $ OSPF not enabled on this interface --More-- ^H^H^H^H^H^H^H^H^H ^H^H^H^H^H^H^H^H^HEthernet0/5 is administratively down, line protocol is $ OSPF not enabled on this interface --More-- ^H^H^H^H^H^H^H^H^H ^H^H^H^H^H^H^H^H^HATM1/0 is administratively down, line protocol is down OSPF not enabled on this interface /******************************************************************************/ /******************************************************************************/ /******************************************************************************/ show ip ospf database ===================== To display information about the ospf database, database contains information about 5 different LSA, the format of these 5 LSA's can be summarized as under: Display OSFP area's link-state database: show ip ospf database area ID Display ASBR summary link advertisements (LS type 4): show ip ospf database asbr-summary show ip ospf database asbr-summary area ID Display AS external link advertisements (LS type 5) show ip ospf database external show ip ospf database external IP address Display network link advertisements (LS type 2) show ip ospf database network show ip ospf database network area ID Display router link advertisements (LS type 1) show ip ospf database router show ip ospf database router area ID Display network summary link advertisements (LS type 3) show ip ospf database summary show ip ospf database summary area ID Type 1 LSA- A router link entry. Broadcast only in a specific area. Contains all the default link state information. Generated by each router for each area to which it belongs. It describes the status of the router's link to the area. These are only flooded within a particular area. The link status and cost are two of the descriptors provided. Type 2 LSA - A network entry. Multicast to all area routers via the DR (Designated Router). Contains network specific information. Describe the set of routers attached to a particular network. These packets are flooded only within the area that contains the network. Type 3 LSA ­ A summary entry with route information for the internal networks and are sent to the backbone routers. Originate with ABRs and describe routes to networks within the local area. Type 4 LSA ­ A summary entry with information about the ASBRs. This information is broadcast by the ABR, and it will reach all the backbone routers. Type 5 LSA ­ An autonomous system entry. Come from the ASBR and have information relating to the external networks. Can be either E1 (External Type-1, which includes the cost of internal links) or E2 (External Type-2, with only the cost of the external route). Use E1 if there are multiple ASBRs advertising routes to the same AS. Output Fields: area--Area number. Area 0.0.0.0 is the backbone area. Type--Type of link advertisement. It can be ASBRSum, Extern, Network, NSSA, Router, or Summary. ID--Link identifier included in the advertise. Adv Rtr--Address of the router that sent the advertisement. Seq--Link sequence number of the advertisement. Age--Age of the advertisement, in seconds. Cksum--Checksum value of the advertisement. For router link-state advertisements: link count--Number of links in the advertisement. /******************************************************************************/ DEXTER: ======= OSPF Router with ID (131.252.215.33) (Process ID 100) Router Link States (Area 0) Link ID ADV Router Age Seq# Checksum Link count 131.252.215.33 131.252.215.33 922 0x80000005 0xF703 2 131.252.215.49 131.252.215.49 1161 0x80000003 0x66C0 1 131.252.215.67 131.252.215.67 1167 0x800000B7 0x8CB7 1 Net Link States (Area 0) Link ID ADV Router Age Seq# Checksum 131.252.215.35 131.252.215.67 1006 0x80000002 0x6925 Summary Net Link States (Area 0) Link ID ADV Router Age Seq# Checksum 131.252.215.48 131.252.215.49 1151 0x80000001 0xF147 131.252.215.48 131.252.215.67 1146 0x80000003 0xE535 131.252.215.64 131.252.215.49 1141 0x80000001 0x5BCC 131.252.215.64 131.252.215.67 1376 0x800000B8 0xCF86 131.252.215.80 131.252.215.49 1141 0x80000001 0xC452 131.252.215.80 131.252.215.67 1360 0x80000003 0xA456 Summary ASB Link States (Area 0) Link ID ADV Router Age Seq# Checksum 131.252.215.67 131.252.215.67 1370 0x80000001 0xEA3A Type-5 AS External Link States Link ID ADV Router Age Seq# Checksum Tag 0.0.0.0 131.252.215.33 926 0x80000001 0x7FD6 100 RADIA: ====== OSPF Router with ID (131.252.215.49) (Process ID 100) Router Link States (Area 0) Link ID ADV Router Age Seq# Checksum Link count 131.252.215.33 131.252.215.33 1089 0x80000005 0xF703 2 131.252.215.49 131.252.215.49 1327 0x80000003 0x66C0 1 131.252.215.67 131.252.215.67 1333 0x800000B7 0x8CB7 1 Net Link States (Area 0) Link ID ADV Router Age Seq# Checksum 131.252.215.35 131.252.215.67 1172 0x80000002 0x6925 Summary Net Link States (Area 0) Link ID ADV Router Age Seq# Checksum 131.252.215.48 131.252.215.49 1318 0x80000001 0xF147 131.252.215.48 131.252.215.67 1313 0x80000003 0xE535 131.252.215.64 131.252.215.49 1308 0x80000001 0x5BCC 131.252.215.64 131.252.215.67 1543 0x800000B8 0xCF86 131.252.215.80 131.252.215.49 1308 0x80000001 0xC452 131.252.215.80 131.252.215.67 1525 0x80000003 0xA456 Summary ASB Link States (Area 0) Link ID ADV Router Age Seq# Checksum 131.252.215.67 131.252.215.67 1535 0x80000001 0xEA3A Router Link States (Area 1) Link ID ADV Router Age Seq# Checksum Link count 131.252.215.49 131.252.215.49 1323 0x80000002 0xD138 1 131.252.215.65 131.252.215.65 1324 0x80000004 0x999 2 131.252.215.67 131.252.215.67 1557 0x800000B5 0x9372 1 131.252.215.81 131.252.215.81 1535 0x80000003 0x9AA8 2 131.252.215.82 131.252.215.82 1537 0x80000002 0x524C 1 Net Link States (Area 1) Link ID ADV Router Age Seq# Checksum 131.252.215.50 131.252.215.65 1325 0x80000001 0x56AB 131.252.215.67 131.252.215.67 1436 0x80000002 0x2C02 131.252.215.82 131.252.215.82 1537 0x80000001 0xFCC2 --More-- Summary Net Link States (Area 1) Link ID ADV Router Age Seq# Checksum 131.252.215.0 131.252.215.49 1168 0x80000001 0x7DFA 131.252.215.0 131.252.215.67 1166 0x80000001 0x6BF1 131.252.215.32 131.252.215.49 1332 0x80000001 0x92B6 131.252.215.32 131.252.215.67 1328 0x800000B6 0x1563 Summary ASB Link States (Area 1) Link ID ADV Router Age Seq# Checksum 131.252.215.33 131.252.215.49 1088 0x80000001 0xD463 131.252.215.33 131.252.215.67 1090 0x80000001 0xC25A 131.252.215.49 131.252.215.49 1333 0x80000001 0xC3D Type-5 AS External Link States Link ID ADV Router Age Seq# Checksum Tag 0.0.0.0 131.252.215.33 1095 0x80000001 0x7FD6 100 TONY: ===== OSPF Router with ID (131.252.215.65) (Process ID 100) Router Link States (Area 1) Link ID ADV Router Age Seq# Checksum Link count 131.252.215.49 131.252.215.49 1469 0x80000002 0xD138 1 131.252.215.65 131.252.215.65 1469 0x80000004 0x999 2 131.252.215.67 131.252.215.67 1702 0x800000B5 0x9372 1 131.252.215.81 131.252.215.81 1680 0x80000003 0x9AA8 2 131.252.215.82 131.252.215.82 73 0x80000003 0x504D 1 Net Link States (Area 1) Link ID ADV Router Age Seq# Checksum 131.252.215.50 131.252.215.65 1469 0x80000001 0x56AB 131.252.215.67 131.252.215.67 1582 0x80000002 0x2C02 131.252.215.82 131.252.215.82 73 0x80000002 0xFAC3 Summary Net Link States (Area 1) Link ID ADV Router Age Seq# Checksum 131.252.215.0 131.252.215.49 1315 0x80000001 0x7DFA 131.252.215.0 131.252.215.67 1311 0x80000001 0x6BF1 131.252.215.32 131.252.215.49 1478 0x80000001 0x92B6 131.252.215.32 131.252.215.67 1473 0x800000B6 0x1563 Summary ASB Link States (Area 1) Link ID ADV Router Age Seq# Checksum 131.252.215.33 131.252.215.49 1234 0x80000001 0xD463 131.252.215.33 131.252.215.67 1234 0x80000001 0xC25A 131.252.215.49 131.252.215.49 1479 0x80000001 0xC3D Type-5 AS External Link States Link ID ADV Router Age Seq# Checksum Tag 0.0.0.0 131.252.215.33 1242 0x80000001 0x7FD6 100 MRHORSE: ======== OSPF Router with ID (131.252.215.67) (Process ID 100) Router Link States (Area 0) Link ID ADV Router Age Seq# Checksum Link count 131.252.215.33 131.252.215.33 1549 0x80000005 0xF703 2 131.252.215.49 131.252.215.49 1787 0x80000003 0x66C0 1 131.252.215.67 131.252.215.67 1792 0x800000B7 0x8CB7 1 Net Link States (Area 0) Link ID ADV Router Age Seq# Checksum 131.252.215.35 131.252.215.67 1632 0x80000002 0x6925 Summary Net Link States (Area 0) Link ID ADV Router Age Seq# Checksum 131.252.215.48 131.252.215.49 1779 0x80000001 0xF147 131.252.215.48 131.252.215.67 1772 0x80000003 0xE535 131.252.215.64 131.252.215.49 1769 0x80000001 0x5BCC 131.252.215.64 131.252.215.67 61 0x800000B9 0xCD87 131.252.215.80 131.252.215.49 1769 0x80000001 0xC452 131.252.215.80 131.252.215.67 62 0x80000004 0xA257 Summary ASB Link States (Area 0) Link ID ADV Router Age Seq# Checksum 131.252.215.67 131.252.215.67 62 0x80000002 0xE83B Router Link States (Area 1) Link ID ADV Router Age Seq# Checksum Link count 131.252.215.49 131.252.215.49 1783 0x80000002 0xD138 1 131.252.215.65 131.252.215.65 1783 0x80000004 0x999 2 131.252.215.67 131.252.215.67 62 0x800000B6 0x9173 1 131.252.215.81 131.252.215.81 2 0x80000004 0x98A9 2 131.252.215.82 131.252.215.82 386 0x80000003 0x504D 1 Net Link States (Area 1) Link ID ADV Router Age Seq# Checksum 131.252.215.50 131.252.215.65 1784 0x80000001 0x56AB 131.252.215.67 131.252.215.67 62 0x80000003 0x2A03 131.252.215.82 131.252.215.82 386 0x80000002 0xFAC3 --More-- Summary Net Link States (Area 1) Link ID ADV Router Age Seq# Checksum 131.252.215.0 131.252.215.49 1629 0x80000001 0x7DFA 131.252.215.0 131.252.215.67 1623 0x80000001 0x6BF1 131.252.215.32 131.252.215.49 1793 0x80000001 0x92B6 131.252.215.32 131.252.215.67 1785 0x800000B6 0x1563 Summary ASB Link States (Area 1) Link ID ADV Router Age Seq# Checksum 131.252.215.33 131.252.215.49 1549 0x80000001 0xD463 131.252.215.33 131.252.215.67 1547 0x80000001 0xC25A 131.252.215.49 131.252.215.49 1793 0x80000001 0xC3D Type-5 AS External Link States Link ID ADV Router Age Seq# Checksum Tag 0.0.0.0 131.252.215.33 1554 0x80000001 0x7FD6 100 YAKOV: ====== OSPF Router with ID (131.252.215.81) (Process ID 100) Router Link States (Area 1) Link ID ADV Router Age Seq# Checksum Link count 131.252.215.49 131.252.215.49 1869 0x80000002 0xD138 1 131.252.215.65 131.252.215.65 5 0x80000005 0x79A 2 131.252.215.67 131.252.215.67 149 0x800000B6 0x9173 1 131.252.215.81 131.252.215.81 86 0x80000004 0x98A9 2 131.252.215.82 131.252.215.82 471 0x80000003 0x504D 1 Net Link States (Area 1) Link ID ADV Router Age Seq# Checksum 131.252.215.50 131.252.215.65 5 0x80000002 0x54AC 131.252.215.67 131.252.215.67 149 0x80000003 0x2A03 131.252.215.82 131.252.215.82 471 0x80000002 0xFAC3 Summary Net Link States (Area 1) Link ID ADV Router Age Seq# Checksum 131.252.215.0 131.252.215.49 1715 0x80000001 0x7DFA 131.252.215.0 131.252.215.67 1712 0x80000001 0x6BF1 131.252.215.32 131.252.215.49 1880 0x80000001 0x92B6 131.252.215.32 131.252.215.67 1874 0x800000B6 0x1563 Summary ASB Link States (Area 1) Link ID ADV Router Age Seq# Checksum 131.252.215.33 131.252.215.49 1636 0x80000001 0xD463 131.252.215.33 131.252.215.67 1635 0x80000001 0xC25A 131.252.215.49 131.252.215.49 1881 0x80000001 0xC3D Type-5 AS External Link States Link ID ADV Router Age Seq# Checksum Tag 0.0.0.0 131.252.215.33 1642 0x80000001 0x7FD6 100 BIG-BABY: ========= OSPF Router with ID (131.252.215.82) (Process ID 100) Router Link States (Area 1) Link ID ADV Router Age Seq# Checksum Link count 131.252.215.49 131.252.215.49 1985 0x80000002 0xD138 1 131.252.215.65 131.252.215.65 120 0x80000005 0x79A 2 131.252.215.67 131.252.215.67 264 0x800000B6 0x9173 1 131.252.215.81 131.252.215.81 202 0x80000004 0x98A9 2 131.252.215.82 131.252.215.82 584 0x80000003 0x504D 1 Net Link States (Area 1) Link ID ADV Router Age Seq# Checksum 131.252.215.50 131.252.215.65 120 0x80000002 0x54AC 131.252.215.67 131.252.215.67 265 0x80000003 0x2A03 131.252.215.82 131.252.215.82 585 0x80000002 0xFAC3 Summary Net Link States (Area 1) Link ID ADV Router Age Seq# Checksum 131.252.215.0 131.252.215.49 1830 0x80000001 0x7DFA 131.252.215.0 131.252.215.67 13 0x80000002 0x69F2 131.252.215.32 131.252.215.49 1994 0x80000001 0x92B6 131.252.215.32 131.252.215.67 13 0x800000B7 0x1364 Summary ASB Link States (Area 1) Link ID ADV Router Age Seq# Checksum 131.252.215.33 131.252.215.49 1750 0x80000001 0xD463 131.252.215.33 131.252.215.67 1749 0x80000001 0xC25A 131.252.215.49 131.252.215.49 1994 0x80000001 0xC3D AS External Link States Link ID ADV Router Age Seq# Checksum Tag 0.0.0.0 131.252.215.33 1756 0x80000001 0x7FD6 100 /*******************************************************************************/ /******************************************************************************/ /******************************************************************************/ show ip ospf neighbor ===================== To display OSPF-neighbor information on a per-interface basis, detials of the various fields are as under: Neighbor ID: Router ID of the neighbor. The router ID is the highest IP address or the highest loopback address (if one is configured) on the Cisco router. Pri: Priority of the neighbor router. The router with the highest priority becomes the designated router (DR). If the priorities are the same, then the router with the highest router ID becomes the DR. By default, priorities are set to 1. A router with a priority of 0 never becomes a DR. State State of the neighbor router. For more information about states, see OSPF Neighbor States. FULL means the router is fully adjacent with its neighbor. Dead Time The amount of time remaining that the router waits to receive an OSPF hello packet from the neighbor before declaring the neighbor down. On broadcast and point-to-point media, the default dead interval is 40 seconds. On non-broadcast and point-to-multipoint links, the default dead interval is 120 seconds. Address The IP address of the interface to which this neighbor is directly connected. In the case of unnumbered links, this field shows the IP address of the interface to which the neighbor is unnumbered. Interface Interface on which the OSPF neighbor has formed adjacency. /********************************************************************************/ DEXTER: ======= Neighbor ID Pri State Dead Time Address Interface 131.252.215.67 1 FULL/DR 00:00:37 131.252.215.35 FastEthernet0/1 131.252.215.49 1 FULL/BDR 00:00:38 131.252.215.34 FastEthernet0/1 RADIA: ====== Neighbor ID Pri State Dead Time Address Interface 131.252.215.33 1 FULL/DROTHER 00:00:33 131.252.215.33 FastEthernet0/0 131.252.215.67 1 FULL/DR 00:00:35 131.252.215.35 FastEthernet0/0 131.252.215.65 1 FULL/DR 00:00:34 131.252.215.50 FastEthernet0/1 TONY: ===== Neighbor ID Pri State Dead Time Address Interface 131.252.215.49 1 FULL/BDR 00:00:39 131.252.215.49 FastEthernet0/0 131.252.215.67 1 FULL/DR 00:00:37 131.252.215.67 FastEthernet0/1 131.252.215.81 1 FULL/BDR 00:00:34 131.252.215.66 FastEthernet0/1 MRHORSE: ======== Neighbor ID Pri State Dead Time Address Interface 131.252.215.33 1 FULL/DROTHER 00:00:36 131.252.215.33 Ethernet0 131.252.215.49 1 FULL/BDR 00:00:38 131.252.215.34 Ethernet0 131.252.215.65 1 FULL/DROTHER 00:00:32 131.252.215.65 Ethernet1 131.252.215.81 1 FULL/BDR 00:00:35 131.252.215.66 Ethernet1 YAKOV: ====== Neighbor ID Pri State Dead Time Address Interface 131.252.215.65 1 FULL/DROTHER 00:00:33 131.252.215.65 FastEthernet0/0 131.252.215.67 1 FULL/DR 00:00:39 131.252.215.67 FastEthernet0/0 131.252.215.82 1 FULL/DR 00:00:36 131.252.215.82 FastEthernet0/1 BIG-BABY: ========= Neighbor ID Pri State Dead Time Address Interface 131.252.215.81 1 FULL/BDR 0:00:32 131.252.215.81 Ethernet0/0 /******************************************************************************/ /******************************************************************************/ /******************************************************************************/ show ip ospf border router ========================== To display the internal OSPF routing table entries to an area border router (ABR) and autonomous system boundary router (ASBR). /******************************************************************************/ DEXTER: ======= OSPF Process 100 internal Routing Table Codes: i - Intra-area route, I - Inter-area route i 131.252.215.49 [1] via 131.252.215.34, FastEthernet0/1, ABR, Area 0, SPF 5 i 131.252.215.67 [1] via 131.252.215.35, FastEthernet0/1, ABR, Area 0, SPF 5 RADIA: ====== OSPF Process 100 internal Routing Table Codes: i - Intra-area route, I - Inter-area route i 131.252.215.33 [1] via 131.252.215.33, FastEthernet0/0, ASBR, Area 0, SPF 6 i 131.252.215.67 [2] via 131.252.215.50, FastEthernet0/1, ABR, Area 1, SPF 3 i 131.252.215.67 [1] via 131.252.215.35, FastEthernet0/0, ABR, Area 0, SPF 6 TONY: ===== OSPF Process 100 internal Routing Table Codes: i - Intra-area route, I - Inter-area route I 131.252.215.33 [2] via 131.252.215.49, FastEthernet0/0, ASBR, Area 1, SPF 6 i 131.252.215.49 [1] via 131.252.215.49, FastEthernet0/0, ABR, Area 1, SPF 6 i 131.252.215.67 [1] via 131.252.215.67, FastEthernet0/1, ABR, Area 1, SPF 6 MRHORSE: ======== OSPF Process 100 internal Routing Table Codes: i - Intra-area route, I - Inter-area route i 131.252.215.33 [10] via 131.252.215.33, Ethernet0, ASBR, Area 0, SPF 12 i 131.252.215.49 [11] via 131.252.215.65, Ethernet1, ABR, Area 1, SPF 17 i 131.252.215.49 [10] via 131.252.215.34, Ethernet0, ABR, Area 0, SPF 12 YAKOV: ====== OSPF Process 100 internal Routing Table Codes: i - Intra-area route, I - Inter-area route I 131.252.215.33 [3] via 131.252.215.65, FastEthernet0/0, ASBR, Area 1, SPF 7 i 131.252.215.49 [2] via 131.252.215.65, FastEthernet0/0, ABR, Area 1, SPF 7 i 131.252.215.67 [1] via 131.252.215.67, FastEthernet0/0, ABR, Area 1, SPF 7 BIG-BABY: ========= OSPF Process 100 internal Routing Table Codes: i - Intra-area route, I - Inter-area route I 131.252.215.33 [13] via 131.252.215.81, Ethernet0/0, ASBR, Area 1, SPF 7 i 131.252.215.49 [12] via 131.252.215.81, Ethernet0/0, ABR, Area 1, SPF 7 i 131.252.215.67 [11] via 131.252.215.81, Ethernet0/0, ABR, Area 1, SPF 7 /******************************************************************************/ /******************************************************************************/ /******************************************************************************/ Changing the cost of an interface ================================= The 'show ip ospf interface' command shows that mrhorse and big-baby have a default cost metric of 10 while all the other routers have a cost metric of 1. OSPF automatically calculates the default cost metric for an interface according to the bandwidth of an interface using the formula: cost = 10^8 / bandwidth The cost of routing a packet throiugh a particular interface can also be explicitly configured for each interface of a router by using the following commands: >interface Ethernet0 >ip ospf cost 1 where Ethernet0 is the interface for which the cost is being changed and 1 is the value that the interface is to be configured with. The cost of routing a packet through a particular interface can be changed back to the default by using the following ospf commands: >interface Ethernet0 >no ip ospf cost /******************************************************************************/ Traceroute from big-baby to dexter with default cost metric =========================================================== big-baby#trace dexter Type escape sequence to abort. Tracing the route to dexter.cs.pdx.edu (131.252.215.4) 1 131.252.215.81 0 msec 0 msec 0 msec 2 131.252.215.65 4 msec 0 msec 4 msec 3 131.252.215.49 4 msec 4 msec 4 msec 4 131.252.215.33 0 msec * 0 msec Change cost of both interfaces of mrhorse ========================================= mrhorse#config t Enter configuration commands, one per line. End with CNTL/Z. mrhorse(config)#interface ethernet 0 mrhorse(config-if)#ip ospf cost 1 mrhorse(config-if)#^Z mrhorse#config t Enter configuration commands, one per line. End with CNTL/Z. mrhorse(config)#interface ethernet 1 mrhorse(config-if)#ip ospf cost 1 mrhorse(config-if)#^Z Traceroute from big-baby to dexter with new cost metrics ======================================================== big-baby#trace dexter Type escape sequence to abort. Tracing the route to dexter.cs.pdx.edu (131.252.215.4) 1 131.252.215.81 0 msec 4 msec 0 msec 2 131.252.215.67 4 msec 4 msec 4 msec 3 131.252.215.33 4 msec * 0 msec This time the path taken was through mrhorse. To get from big-baby to dexter through mrhorse takes only two hops of cost 1 each while to get from big-baby to dexter through tony and Radia takes 3 hops of cost 1 each, hence the path chosen was through mrhorse. /******************************************************************************/ /******************************************************************************/ /******************************************************************************/