[c-nsp] Traffic Engineering Internet links automatically

[Pete Templin]

Kim Onnel wrote:
> I am sure someone has been in my place before and there is something that
> can be done on this matter, i'll try to explain again in more details, maybe
> i missed something, i hope i can get suggestions on Best practices for this
> 
> 
> upstream \
> upstream ---- multiple links ----- GW-INTERNET---
> upstream /
> 
> the multiple links are all terminated on our side at 1 router (GW-INTERNET)
> and the upstream isnt 1 router, but same AS
> 
> Lets say i have 3 PoS and 2 Giga
> 
> My manager wakes up each day, checks MRTG, finds that the Giga has some room
> and that PoS is full, so he tells me to move some networks around to achieve
> this, as Gert said above, it is time consuming, specially when moving 1 /24
> doesnt do it and half of my day is spent in excel sheets and updating
> everyone ?
> 
> What is the correct thing to be done here ?

Ah, more clarification.  Didn't realize that it was the same AS.

Announce all prefixes on all links.  For each of your network 
statements, add "route-map mytuning" to the end.

ip prefix-list prefer-link1 permit x.x.x.x/y
ip prefix-list prefer-link2 permit a.a.a.a/b
...
ip community-list 11 permit myAS:1
ip community-list 12 permit myAS:2
ip community-list 13 permit myAS:3
ip community-list 101 permit myAS:.
...
!
route-map mytuning permit 10
  match prefix-list prefer-link1
  set commu myAS:1
!
route-map mytuning permit 20
  match prefix-list prefer-link2
  set commu myAS:2
!
route-map mytuning permit 30
  match prefix-list prefer-link3
  set commu myAS:3
!
!(more as needed)
!
route-map mytuning permit 99
!
route-map link1-out permit 10
  match commu 11
  set metric 200
!
route-map link1-out permit 100
  match commu 101
  set metric 400
!
route-map link1-out permit 110
  set metric 300
!
route-map link2-out permit 10
  match commu 12
  set metric 200
!
route-map link2-out permit 100
  match commu 101
  set metric 400
!
route-map link2-out permit 110
  set metric 300
!

Then apply route-map linkX-out to neighbor X.

All you need to do to tune is change the prefix-lists and soft-clear 
your sessions outbound.

pt