Cisco IOS OSPF Example
Cisco IOS OSPF Example
In this example, there are two routers connected by a single link and OSPF is enabled to advertise the static routes into OSPF.
R0
Here is the R0 configuration:
R0>
R0>en
R0#show run
R0#show running-config
Building configuration...
Current configuration : 864 bytes
!
version 15.1
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname R0
!
!
!
!
!
!
!
!
ip cef
no ipv6 cef
!
!
!
!
license udi pid CISCO2911/K9 sn FTX1524A0OO-
!
!
!
!
!
!
!
!
!
no ip domain-lookup
!
!
spanning-tree mode pvst
!
!
!
!
!
!
interface GigabitEthernet0/0
ip address 192.168.1.1 255.255.255.0
duplex auto
speed auto
!
interface GigabitEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface GigabitEthernet0/2
no ip address
duplex auto
speed auto
shutdown
!
interface Vlan1
no ip address
shutdown
!
router ospf 1
log-adjacency-changes
redistribute static subnets
network 192.168.1.0 0.0.0.255 area 0
!
ip classless
ip route 10.0.0.0 255.255.255.0 Null0
!
ip flow-export version 9
!
!
!
!
!
!
!
line con 0
!
line aux 0
!
line vty 0 4
login
!
!
!
end
R0#show ip int br
Interface IP-Address OK? Method Status Protocol
GigabitEthernet0/0 192.168.1.1 YES manual up up
GigabitEthernet0/1 unassigned YES unset administratively down down
GigabitEthernet0/2 unassigned YES unset administratively down down
Vlan1 unassigned YES unset administratively down down
R0#show ip route
Codes: L - local, C - connected, S - static, 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 not set
10.0.0.0/24 is subnetted, 1 subnets
S 10.0.0.0/24 is directly connected, Null0
172.16.0.0/24 is subnetted, 1 subnets
O E2 172.16.1.0/24 [110/20] via 192.168.1.2, 00:12:54, GigabitEthernet0/0
192.168.1.0/24 is variably subnetted, 2 subnets, 2 masks
C 192.168.1.0/24 is directly connected, GigabitEthernet0/0
L 192.168.1.1/32 is directly connected, GigabitEthernet0/0
R0#show ip prot
R0#show ip protocols
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 192.168.1.1
It is an autonomous system boundary router
Redistributing External Routes from,
static
Number of areas in this router is 1. 1 normal 0 stub 0 nssa
Maximum path: 4
Routing for Networks:
192.168.1.0 0.0.0.255 area 0
Routing Information Sources:
Gateway Distance Last Update
192.168.1.1 110 00:21:37
192.168.1.2 110 00:13:03
Distance: (default is 110)
R0#show ip ospf ne
R0#show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
192.168.1.2 1 FULL/BDR 00:00:31 192.168.1.2 GigabitEthernet0/0
R0#show ip ospf data
R0#show ip ospf database
OSPF Router with ID (192.168.1.1) (Process ID 1)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
192.168.1.1 192.168.1.1 1309 0x80000004 0x00f4ad 1
192.168.1.2 192.168.1.2 795 0x80000005 0x00f0ad 1
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
192.168.1.1 192.168.1.1 888 0x80000003 0x004f5c
Type-5 AS External Link States
Link ID ADV Router Age Seq# Checksum Tag
10.0.0.0 192.168.1.1 1309 0x80000001 0x002e1d 0
172.16.1.0 192.168.1.2 795 0x80000001 0x001a7c 0
R0#
R1
Here is the R1 configuration:
R1#show running-config
Building configuration...
Current configuration : 866 bytes
!
version 15.1
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname R1
!
!
!
!
!
!
!
!
ip cef
no ipv6 cef
!
!
!
!
license udi pid CISCO2911/K9 sn FTX1524NTR6-
!
!
!
!
!
!
!
!
!
no ip domain-lookup
!
!
spanning-tree mode pvst
!
!
!
!
!
!
interface GigabitEthernet0/0
ip address 192.168.1.2 255.255.255.0
duplex auto
speed auto
!
interface GigabitEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface GigabitEthernet0/2
no ip address
duplex auto
speed auto
shutdown
!
interface Vlan1
no ip address
shutdown
!
router ospf 1
log-adjacency-changes
redistribute static subnets
network 192.168.1.0 0.0.0.255 area 0
!
ip classless
ip route 172.16.1.0 255.255.255.0 Null0
!
ip flow-export version 9
!
!
!
!
!
!
!
line con 0
!
line aux 0
!
line vty 0 4
login
!
!
!
end
R1#
R1#show ip int br
Interface IP-Address OK? Method Status Protocol
GigabitEthernet0/0 192.168.1.2 YES manual up up
GigabitEthernet0/1 unassigned YES unset administratively down down
GigabitEthernet0/2 unassigned YES unset administratively down down
Vlan1 unassigned YES unset administratively down down
R1#show ip route
Codes: L - local, C - connected, S - static, 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 not set
10.0.0.0/24 is subnetted, 1 subnets
O E2 10.0.0.0/24 [110/20] via 192.168.1.1, 00:17:50, GigabitEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.1.0/24 is directly connected, Null0
192.168.1.0/24 is variably subnetted, 2 subnets, 2 masks
C 192.168.1.0/24 is directly connected, GigabitEthernet0/0
L 192.168.1.2/32 is directly connected, GigabitEthernet0/0
R1#show ip pro
R1#show ip protocols
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 192.168.1.2
It is an autonomous system boundary router
Redistributing External Routes from,
static
Number of areas in this router is 1. 1 normal 0 stub 0 nssa
Maximum path: 4
Routing for Networks:
192.168.1.0 0.0.0.255 area 0
Routing Information Sources:
Gateway Distance Last Update
192.168.1.1 110 00:17:56
192.168.1.2 110 00:09:22
Distance: (default is 110)
R1#show ip ospf ne
Neighbor ID Pri State Dead Time Address Interface
192.168.1.1 1 FULL/DR 00:00:38 192.168.1.1 GigabitEthernet0/0
R1#show ip ospf da
R1#show ip ospf database
OSPF Router with ID (192.168.1.2) (Process ID 1)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
192.168.1.1 192.168.1.1 1093 0x80000004 0x00f4ad 1
192.168.1.2 192.168.1.2 579 0x80000005 0x00f0ad 1
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
192.168.1.1 192.168.1.1 672 0x80000003 0x004f5c
Type-5 AS External Link States
Link ID ADV Router Age Seq# Checksum Tag
10.0.0.0 192.168.1.1 1093 0x80000001 0x002e1d 0
172.16.1.0 192.168.1.2 579 0x80000001 0x001a7c 0
R1#
OSPF Database view from IOS
R0#show ip ospf database ?
asbr-summary ASBR summary link states
external External link states
network Network link states
router Router link states
summary Network summary link states
<cr>
R0#show ip ospf database ro
R0#show ip ospf database router
OSPF Router with ID (192.168.1.1) (Process ID 1)
Router Link States (Area 0)
LS age: 1364
Options: (No TOS-capability, DC)
LS Type: Router Links
Link State ID: 192.168.1.1
Advertising Router: 192.168.1.1
LS Seq Number: 80000004
Checksum: 0xf4ad
Length: 36
AS Boundary Router
Number of Links: 1
Link connected to: a Transit Network
(Link ID) Designated Router address: 192.168.1.1
(Link Data) Router Interface address: 192.168.1.1
Number of TOS metrics: 0
TOS 0 Metrics: 1
LS age: 850
Options: (No TOS-capability, DC)
LS Type: Router Links
Link State ID: 192.168.1.2
Advertising Router: 192.168.1.2
LS Seq Number: 80000005
Checksum: 0xf0ad
Length: 36
AS Boundary Router
Number of Links: 1
Link connected to: a Transit Network
(Link ID) Designated Router address: 192.168.1.1
(Link Data) Router Interface address: 192.168.1.2
Number of TOS metrics: 0
TOS 0 Metrics: 1
R0#show ip ospf database n
R0#show ip ospf database network
OSPF Router with ID (192.168.1.1) (Process ID 1)
Net Link States (Area 0)
Routing Bit Set on this LSA
LS age: 952
Options: (No TOS-capability, DC)
LS Type: Network Links
Link State ID: 192.168.1.1 (address of Designated Router)
Advertising Router: 192.168.1.1
LS Seq Number: 80000003
Checksum: 0x4f5c
Length: 32
Network Mask: /24
Attached Router: 192.168.1.2
Attached Router: 192.168.1.1
R0#show ip ospf database su
R0#show ip ospf database summary
OSPF Router with ID (192.168.1.1) (Process ID 1)
R0#show ip ospf database ex
R0#show ip ospf database external
OSPF Router with ID (192.168.1.1) (Process ID 1)
Type-5 AS External Link States
Routing Bit Set on this LSA
LS age: 1384
Options: (No TOS-capability, DC)
LS Type: AS External Link
Link State ID: 10.0.0.0 (External Network Number )
Advertising Router: 192.168.1.1
LS Seq Number: 80000001
Checksum: 0x2e1d
Length: 36
Network Mask: /24
Metric Type: 2 (Larger than any link state path)
TOS: 0
Metric: 20
Forward Address: 0.0.0.0
External Route Tag: 0
Routing Bit Set on this LSA
LS age: 870
Options: (No TOS-capability, DC)
LS Type: AS External Link
Link State ID: 172.16.1.0 (External Network Number )
Advertising Router: 192.168.1.2
LS Seq Number: 80000001
Checksum: 0x1a7c
Length: 36
Network Mask: /24
Metric Type: 2 (Larger than any link state path)
TOS: 0
Metric: 20
Forward Address: 0.0.0.0
External Route Tag: 0
R0#show ip ospf database external ?
<cr>
R0#show ip ospf database ?
asbr-summary ASBR summary link states
external External link states
network Network link states
router Router link states
summary Network summary link states
<cr>
R0#show ip ospf database as
R0#show ip ospf database asbr-summary
OSPF Router with ID (192.168.1.1) (Process ID 1)
R0#
