Why is it duplicate ip address error message in vrf ospf configuration ?

[eigrpy]

Hi I am getting duplicate ip address error message when setting up ospf between two routers. I checked several times and i did not find there duplicate ip address. Here is topology R3(e1/0) ------(e1/1)R1. at the moment, the two routers cannot have ospf neighbor to each other, and they can ping each other.   Anyone can give me some suggestion ? Thank you 

Here is config

R3(config)#do sh run

ip vrf POD1
 rd 1:1

interface Ethernet1/0
 ip vrf forwarding POD1
 ip address 13.1.1.3 255.255.255.0
 half-duplex
!
interface Ethernet1/1
 no ip address
 half-duplex

router ospf 1 vrf POD1
 log-adjacency-changes
 network 13.1.1.0 0.0.0.255 area 0
!

R3 --- error message: 

*Mar  1 00:27:02.327: %OSPF-4-DUP_RTRID_NBR: OSPF detected duplicate router-id 13.1.1.1 from 13.1.1.1 on interface Ethernet1/0
 
*Mar  1 00:28:02.331: %OSPF-4-DUP_RTRID_NBR: OSPF detected duplicate router-id 13.1.1.1 from 13.1.1.1 on interface Ethernet1/0

R3(config)#do sh ip int bri
Interface                  IP-Address      OK? Method Status                Protocol
Ethernet1/0                13.1.1.3        YES manual up                    up
Ethernet1/1                unassigned      YES TFTP   up                    up
Ethernet1/2                unassigned      YES NVRAM  administratively down down
Ethernet1/3                unassigned      YES NVRAM  administratively down down

---------------------------------------------------

R1(config-router)#do sh run
!
interface Ethernet1/1
 ip address 13.1.1.1 255.255.255.0
 duplex half
!
router ospf 1
 log-adjacency-changes
 network 13.1.1.0 0.0.0.255 area 0

R1(config-router)#do sh ip int bri
Interface                  IP-Address      OK? Method Status                Protocol
FastEthernet0/0            unassigned      YES unset  administratively down down
Ethernet1/1                13.1.1.1        YES manual up                    up

R1 --- error message

*Oct  6 12:22:21.346: %OSPF-4-DUP_RTRID_NBR: OSPF detected duplicate router-id 13.1.1.1 from 13.1.1.3 on interface Ethernet1/1
*Oct  6 12:23:21.354: %OSPF-4-DUP_RTRID_NBR: OSPF detected duplicate router-id 13.1.1.1 from 13.1.1.3 on interface Ethernet1/1

[Peter Paluch]

Hello,

This is not a duplicate IP address but rather a duplicate OSPF Router ID. Is it possible that you've made a typo in your IP addresses, started OSPF and only then corrected the addresses? Once an OSPF process has chosen its Router ID, it won't change it until completely deconfigured and reconfigured, or until the Router ID is set manually and the process is restarted.

Try entering the following commands on R3:

configure terminal
router ospf 1
 router-id 13.1.1.3
end
clear ip ospf process ! Answer yes when asked

Best regards,
Peter

[eigrpy]

Thank you so much for your reply. You are exactly right. Usually I do not have this issue when I configured common ospf. Maybe vrf ospf requires router-id, right ?