I am new to this so forgive me for mistakes, but I feel like I am missing something here.
I am trying to use a loopback address as the router ID for Router0 in my network. I am typing in:
Router(config)#int loopback 0
Router(config-if)#ip address 1.1.1.1 255.255.255.255
Router(config-if)#
Router(config-if)#exit
Router(config)#do show ip int brief
Interface IP-Address OK? Method Status Protocol
FastEthernet0/0 150.45.101.1 YES manual up up
FastEthernet1/0 unassigned YES unset administratively down down
Serial2/0 200.200.200.3 YES manual up up
Serial3/0 unassigned YES unset administratively down down
FastEthernet4/0 unassigned YES unset administratively down down
FastEthernet5/0 unassigned YES unset administratively down down
Loopback0 1.1.1.1 YES manual up up
Router(config)#
So we can see that the loopback has been configured, but when I show the router ID it is still showing the serial interface as its ID.
Router(config)#do show ip ospf
Routing Process "ospf 100" with ID 200.200.200.3
Supports only single TOS(TOS0) routes
Supports opaque LSA
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 0. Checksum Sum 0x000000
Number of opaque AS LSA 0. Checksum Sum 0x000000
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 2. 2 normal 0 stub 0 nssa
External flood list length 0
Area BACKBONE(0) (Inactive)
Number of interfaces in this area is 0
Area has no authentication
SPF algorithm executed 5 times
Area ranges are
Number of LSA 2. Checksum Sum 0x0137ce
Number of opaque link LSA 0. Checksum Sum 0x000000
Number of DCbitless LSA 0
Number of indication LSA 0
Number of DoNotAge LSA 0
Flood list length 0
Area 1
Number of interfaces in this area is 1
Area has no authentication
SPF algorithm executed 2 times
Area ranges are
Number of LSA 0. Checksum Sum 0x000000
Number of opaque link LSA 0. Checksum Sum 0x000000
Number of DCbitless LSA 0
Number of indication LSA 0
Number of DoNotAge LSA 0
Flood list length 0
To resolve this problem I tried this:
Router(config)#do clear ip ospf process
Reset ALL OSPF processes? [no]: y
Router(config)#
But when I run this command again I am getting the same results:
Router(config)#do show ip ospf
Routing Process "ospf 100" with ID 200.200.200.3
Supports only single TOS(TOS0) routes
Supports opaque LSA
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 0. Checksum Sum 0x000000
Number of opaque AS LSA 0. Checksum Sum 0x000000
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 2. 2 normal 0 stub 0 nssa
External flood list length 0
Area BACKBONE(0) (Inactive)
Number of interfaces in this area is 0
Area has no authentication
SPF algorithm executed 5 times
Area ranges are
Number of LSA 2. Checksum Sum 0x0137ce
Number of opaque link LSA 0. Checksum Sum 0x000000
Number of DCbitless LSA 0
Number of indication LSA 0
Number of DoNotAge LSA 0
Flood list length 0
Area 1
Number of interfaces in this area is 1
Area has no authentication
SPF algorithm executed 2 times
Area ranges are
Number of LSA 0. Checksum Sum 0x000000
Number of opaque link LSA 0. Checksum Sum 0x000000
Number of DCbitless LSA 0
Number of indication LSA 0
Number of DoNotAge LSA 0
Flood list length 0
And here is the running-config:
Router(config-if)#do show running-config
Building configuration...
Current configuration : 887 bytes
!
version 12.2
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname Router
!
ip cef
no ipv6 cef
!
interface Loopback0
ip address 1.1.1.1 255.255.255.255
!
interface FastEthernet0/0
ip address 150.45.101.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet1/0
no ip address
duplex auto
speed auto
shutdown
!
interface Serial2/0
ip address 200.200.200.3 255.255.255.0
!
interface Serial3/0
no ip address
shutdown
!
interface FastEthernet4/0
no ip address
shutdown
!
interface FastEthernet5/0
no ip address
shutdown
!
router ospf 100
log-adjacency-changes
network 150.45.101.0 0.0.0.7 area 0
network 200.200.200.0 0.0.0.3 area 0
!
ip classless
!
ip flow-export version 9
!
line con 0
!
line aux 0
!
line vty 0 4
login
!
end
As we can see the router ID did not change, what is it that I am doing wrong here?
show running-config
). Simply paste it into the question, and use the Preformatted Text ({}
) button on it.no router ospf 100
), then add it back to see if it picks up the loopback. If not, it may be that you are not including that interface in the OSPF process. It is hard to say what Packet Tracer is doing. The best practice is to specifically set the OSPF router ID with therouter-id <router-id>
command.