OSPF Rout metric

OSPF Rout metric

o
in the topology above I configured OSPF on R3 for all interfaces. R1 and R2 are configured both with OSPF and RIP. Interfaces connected to R3 are in the OSPF domain

R2 learned OSPF routes from R3 . I can see the metric is 110/20 for the physical interfaces but the metric for the route on the loopback is 110/11

I am not sure why. Though I adjusted the bandwidth , delay , mtu of the Loopback to be the same as the physical interface.


R2#sh ip route ospf
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
       i - IS-IS, su - IS-IS summary, 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, H - NHRP, l - LISP
       a - application route
       + - replicated route, % - next hop override

Gateway of last resort is not set

      3.0.0.0/32 is subnetted, 1 subnets
O        3.3.3.3 [110/11] via 192.168.23.3, 00:01:19, Ethernet0/0
O     192.168.13.0/24 [110/20] via 192.168.23.3, 00:01:19, Ethernet0/0
O E2  192.168.14.0/24 [110/20] via 192.168.23.3, 00:01:19, Ethernet0/0
R2#


R3#sh interfaces e0/0
Ethernet0/0 is up, line protocol is up
  Hardware is AmdP2, address is aabb.cc00.0300 (bia aabb.cc00.0300)
  Internet address is 192.168.13.3/24
  MTU 1500 bytes, BW 10000 Kbit/sec, DLY 1000 usec,
     reliability 255/255, txload 1/255, rxload 1/255


R3#sh interfaces loopback 0
Loopback0 is up, line protocol is up
  Hardware is Loopback
  Internet address is 3.3.3.3/24
  MTU 1514 bytes, BW 10000 Kbit/sec, DLY 10000 usec,
     reliability 255/255, txload 1/255, rxload 1/255

Any Expert to clear up the confusion.

Thank you
jskfanAsked:
Who is Participating?
 
JustInCaseCommented:
By default loopbacks and SVIs is assigned cost of 1.
For 10Mb interface cost is 100/10=10.

Configuring bandwidth on loopback interface is not affecting OSPF cost of loopback.
0
 
Don JohnstonInstructorCommented:
Please post the output of a "show ip ospf interface" for the interfaces in question.
0
 
jskfanAuthor Commented:
I got it. Thank you
0
Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.

All Courses

From novice to tech pro — start learning today.