autoroute metric absolute

EdTheLad · January 2015

I thought the idea behind the subcommand "absolute" was that all prefixes behind the tunnel would be given this metric?

interface Tunnel1
 ip unnumbered Loopback0
 tunnel destination 4.4.4.4
 tunnel mode mpls traffic-eng
 tunnel mpls traffic-eng autoroute announce
 tunnel mpls traffic-eng autoroute metric absolute 10
 tunnel mpls traffic-eng path-option 5 explicit name TEST
 no routing dynamic

R2#sh ip route 4.4.4.4
Routing entry for 4.4.4.4/32
  Known via "ospf 1", distance 110, metric 11, type intra area
  Last update from 4.4.4.4 on Tunnel1, 00:14:56 ago
  Routing Descriptor Blocks:
  * 4.4.4.4, from 4.4.4.4, 00:14:56 ago, via Tunnel1
      Route metric is 11, traffic share count is 1

R2#sh ip route 8.8.8.8
Routing entry for 8.8.8.8/32
  Known via "ospf 1", distance 110, metric 21, type intra area
  Last update from 4.4.4.4 on Tunnel1, 00:15:02 ago
  Routing Descriptor Blocks:
  * 4.4.4.4, from 8.8.8.8, 00:15:02 ago, via Tunnel1
      Route metric is 21, traffic share count is 1

I was expecting both prefixes to have a cost of 10.
If i remove the absolute and just have metric i get the same result.

interface Tunnel1
 ip unnumbered Loopback0
 tunnel destination 4.4.4.4
 tunnel mode mpls traffic-eng
 tunnel mpls traffic-eng autoroute announce
 tunnel mpls traffic-eng autoroute metric 10
 tunnel mpls traffic-eng path-option 5 explicit name TEST
 no routing dynamic

R2#sh ip route 4.4.4.4
Routing entry for 4.4.4.4/32
  Known via "ospf 1", distance 110, metric 11, type intra area
  Last update from 4.4.4.4 on Tunnel1, 00:01:23 ago
  Routing Descriptor Blocks:
  * 4.4.4.4, from 4.4.4.4, 00:01:23 ago, via Tunnel1
      Route metric is 11, traffic share count is 1

R2#sh ip route 8.8.8.8
Routing entry for 8.8.8.8/32
  Known via "ospf 1", distance 110, metric 21, type intra area
  Last update from 4.4.4.4 on Tunnel1, 00:01:25 ago
  Routing Descriptor Blocks:
  * 4.4.4.4, from 8.8.8.8, 00:01:25 ago, via Tunnel1
      Route metric is 21, traffic share count is 1

So what exactly is the absolute subcommand doing for me?

fredrikjj · August 2015

I don't know if you're still wondering about this Ed, but I remembered this thread when I read some notes I had on the Cisco Press TE book. Your problem is probably that you're using OSPF:

Only IS-IS supports tunnel mpls traffic-eng autoroute metric absolute; if you configure absolute metrics on an OSPF network, it's just ignored.

https://books.google.se/books?id=hpE0xIGx0pkC&pg=PA232&lpg=PA232&dq=Only+IS-IS+supports+tunnel+mpls+traffic-eng+autoroute+metric+absolute;+if+you+configure+absolute+metrics+on+an+OSPF+network,+it%27s+just+ignored.&source=bl&ots=_JWGrrxXMz&sig=a3MQRcFbZgrQLiS59QRhwUq3yzc&hl=sv&sa=X&ved=0CCEQ6AEwAGoVChMIveOdmo_KxwIVxSxyCh3GTgW4#v=onepage&q=Only%20IS-IS%20supports%20tunnel%20mpls%20traffic-eng%20autoroute%20metric%20absolute%3B%20if%20you%20configure%20absolute%20metrics%20on%20an%20OSPF%20network%2C%20it's%20just%20ignored.&f=false

The book's fairly old (2002 I think) so it might have nothing to do with this at all...

autoroute metric absolute

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