[j-nsp] BGP/MPLS Question MX Platform

[Dean B]

Ok, I have attempted to lab this up...config here
http://pastebin.com/53Ebsd7X

I must still be missing something...BGP appears to still use the IGP and go
across the high-cost link when I disable the low-cost link between B-C:

(on B)
2.2.2.0/24         *[BGP/170] 00:12:13, localpref 100, from 10.10.10.1
                      AS path: 174 I, validation-state: unverified
                    > to 10.0.1.1 via lt-0/0/10.2, label-switched-path
LSP-B-C-L2VPN

The other LSPs do drop that should not be going over the high-cost link.
I'm guessing I need some knob to tell BGP which LSP to use or not to use?

dean at lab# run show rsvp session logical-system A
Ingress RSVP: 1 sessions
To              From            State   Rt Style Labelin Labelout LSPname
10.10.10.2      10.10.10.3      Up       0  1 FF       -        3 LSP-A-B
Total 1 displayed, Up 1, Down 0

Egress RSVP: 1 sessions
To              From            State   Rt Style Labelin Labelout LSPname
10.10.10.3      10.10.10.2      Up       0  1 FF       3        - LSP-B-A
Total 1 displayed, Up 1, Down 0

Transit RSVP: 2 sessions
To              From            State   Rt Style Labelin Labelout LSPname
10.10.10.1      10.10.10.2      Up       0  1 FF  299792        3
LSP-B-C-L2VPN
10.10.10.2      10.10.10.1      Up       0  1 FF  299808        3
LSP-C-B-L2VPN
Total 2 displayed, Up 2, Down 0

dean at lab# run show rsvp session logical-system B
Ingress RSVP: 2 sessions
To              From            State   Rt Style Labelin Labelout LSPname
10.10.10.1      10.10.10.2      Up       0  1 FF       -   299792
LSP-B-C-L2VPN
10.10.10.3      10.10.10.2      Up       0  1 FF       -        3 LSP-B-A
Total 2 displayed, Up 2, Down 0

Egress RSVP: 2 sessions
To              From            State   Rt Style Labelin Labelout LSPname
10.10.10.2      10.10.10.3      Up       0  1 FF       3        - LSP-A-B
10.10.10.2      10.10.10.1      Up       0  1 FF       3        -
LSP-C-B-L2VPN
Total 2 displayed, Up 2, Down 0

Transit RSVP: 0 sessions
Total 0 displayed, Up 0, Down 0

dean at lab# run show rsvp session logical-system C
Ingress RSVP: 1 sessions
To              From            State   Rt Style Labelin Labelout LSPname
10.10.10.2      10.10.10.1      Up       0  1 FF       -   299808
LSP-C-B-L2VPN
Total 1 displayed, Up 1, Down 0

Egress RSVP: 1 sessions
To              From            State   Rt Style Labelin Labelout LSPname
10.10.10.1      10.10.10.2      Up       0  1 FF       3        -
LSP-B-C-L2VPN
Total 1 displayed, Up 1, Down 0

Transit RSVP: 0 sessions
Total 0 displayed, Up 0, Down 0

On Wed, Aug 3, 2016 at 12:18 PM, Saku Ytti <saku at ytti.fi> wrote:

> On 3 August 2016 at 19:36, Dean B <jnprlist at gmail.com> wrote:
>
> Hey,
>
> > Hey Saku thanks for clarifying...it makes sense now.  So for your option
> "c"
> > I would just set the ISIS metric to have a higher cost on the expensive
> A-C
> > link so that it would not normally be used right?  I have sample lab
> logical
> > system config here: http://pastebin.com/uzHtzWrw
>
> No. In option C you'd have proper metric, metric which cases expensive
> link to be used normally. But as all traffic would be in RSVP tunnels,
> you'd ultimately be unable to put LSPs on the SPT path, because there
> isn't enough capacity, then subsequent LSPs would fall back to off SPT
> paths, to avoid the congested link.
> And if there are no available path, then some LPSs would just simply
> not establish and you'd blackhole traffic.
>
> > I'm assuming I need to add an additional LSP to each node that has a
> higher
> > priority and then use that LSP for the l2circuit traffic.  What else
> would I
> > need to get the option "c" with blackhole of other traffic during
> low-cost
> > path failure?
>
> For C you'd need need full-mesh RSVP.
>
> --
>   ++ytti
>