Compare OSPF metric-type 1 and 2

acbenny · ‎07-04-2008

Hi,

I try to redistribute static route 188.188.188.0/24 from Router 16A and 16B

with metric-type 2 and metric-type 1 respectively. I think metric 2 will be chosen by Router 2600

as lower metric (20) compared with metric 1 (30).

However, after simulation, router 2600 has route {E1 188.188.188.0 [110/30] via 172.20.1.1}

installed. After Router 2600 E0/1 down. 2600 has route {E2 188.188.188.0 [110/20] via 192.168.1.1}

installed

Anyone know why Router 2600 chose E1 route rather than E2 route ?

jpl861 · ‎07-04-2008

E1 is always better than E2 route even though the metric is lower.

HTH,

John

ccnpninja · ‎10-20-2008

Is it an exception in routing?

Logically, router 2600 will choose to insert the E2 route in its routing table because it has a lower metric (both routes having the same prefix and the same Admin Distance).

Am I missing something?

Giuseppe Larosa · ‎10-20-2008

Hello Wassim,

O E1 are preferred over O E2 because they are seen as more detailed for the fact that the metric is the sum of seed metric and internal metric to ASBR: see your own thread on O E1 metrics as seen by neighbor.

Hope to help

Giuseppe