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Install next-hop LSP from a prefix advertised by multiple PE

‎12-01-2018 10:22 AM

Dear Experts,

 

I need your support to understand what is going on when it comes to install next-hop LSP  from a prefix which is advertised by multiple PE at the same time.

 

In this case IP 10.10.10.0/29 is connected to R3 & R4. Hence, it's avertised from both routers to R1 and R2.

 

Eg. Route to 10.10.10.0/29 from R2 show 4 LSPs :

1. Two from router-id 4.4.4.4 --- LSP R2-toR4 and LSP R2-to-R4-2 (via R1-R2)

1. Two from router-id 3.3.3.3 -- LSP R1-to-R3 and LSP R1-to-R3-2 (via R1-R2)

 

topo_lsp.png

 

lo0.X : X.X.X.X/32 (eg. R1, lo0.1: 1.1.1.1/32)

R1<->R2 P2P 12.12.12.0/30
R1<->R3 P2P 13.13.13.0/30
R2<->R4 P2P 24.24.24.0/30
R3<->R4 P2P 34.34.34.0/30

MP-BGP is over MPLS/RSVP

R3<->R5 10.10.10.0/29 (eg. R3 10.10.10.3/29)
R4<->R5 10.10.10.0/29
R3,R4 & R5 withing OSPF AREA 0.

R5 is CE. Others are PE.

 

The aim is to force the MPLS to use LSP R2-to-R4 from R2 and R1-to-R2 from R2 when it comes sto reach prefix 10.10.10.0/29. Then in case R2-R4 link is down, the R1-R3 link may be use as a backup.

I did map same prefix on LSP R2-to-R4-2 but it's not working.

 

The configuration is as per below :


set logical-systems R1 policy-options policy-statement MAP_TO_LSP term 1 from protocol bgp
set logical-systems R1 policy-options policy-statement MAP_TO_LSP term 1 from route-filter 10.10.10.0/29 orlonger
set logical-systems R1 policy-options policy-statement MAP_TO_LSP term 1 then install-nexthop lsp R1-to-R4-2
set logical-systems R1 policy-options policy-statement MAP_TO_LSP term 1 then accept

 

set logical-systems R1 routing-options forwarding-table export MAP_TO_LSP
set logical-systems R1 routing-options forwarding-table export load-balance

 

set logical-systems R1 protocols mpls label-switched-path R1-to-R4 to 4.4.4.4
set logical-systems R1 protocols mpls label-switched-path R1-to-R4 primary via-R1-R3
set logical-systems R1 protocols mpls label-switched-path R1-to-R4-2 to 4.4.4.4
set logical-systems R1 protocols mpls label-switched-path R1-to-R4-2 primary via-R1-R2
set logical-systems R1 protocols mpls label-switched-path R1-to-R3 to 3.3.3.3
set logical-systems R1 protocols mpls label-switched-path R1-to-R3 primary via-R1-R3
set logical-systems R1 protocols mpls label-switched-path R1-to-R3-2 to 3.3.3.3
set logical-systems R1 protocols mpls label-switched-path R1-to-R3-2 primary via-R1-R2
set logical-systems R1 protocols mpls label-switched-path R1-to-R2 to 2.2.2.2
set logical-systems R1 protocols mpls label-switched-path R1-to-R2 primary via-R1-R2
set logical-systems R1 protocols mpls label-switched-path R1-to-R2-2 to 2.2.2.2
set logical-systems R1 protocols mpls label-switched-path R1-to-R2-2 primary via-R1-R3
set logical-systems R1 protocols mpls path via-R1-R2 12.12.12.2 strict
set logical-systems R1 protocols mpls path via-R1-R3 13.13.13.2 strict
set logical-systems R1 protocols mpls interface lt-0/0/0.12
set logical-systems R1 protocols mpls interface lt-0/0/0.13

 

 

Below the logs once the above routing policy is applied :

 

admin@vMX-1:R1> show route 10.10.10.1    

5_VRF.inet.0: 6 destinations, 10 routes (6 active, 0 holddown, 0 hidden)
+ = Active Route, - = Last Active, * = Both

10.10.10.0/29      *[BGP/170] 00:05:33, localpref 100, from 3.3.3.3
                      AS path: I, validation-state: unverified
                      to 13.13.13.2 via lt-0/0/0.13, label-switched-path R1-to-R3
                    > to 12.12.12.2 via lt-0/0/0.12, label-switched-path R1-to-R3-2
                    [BGP/170] 00:05:33, localpref 100, from 4.4.4.4
                      AS path: I, validation-state: unverified
                      to 12.12.12.2 via lt-0/0/0.12, label-switched-path R1-to-R4-2

admin@vMX-1:R1> show route 10.10.10.1 active-path

5_VRF.inet.0: 6 destinations, 10 routes (6 active, 0 holddown, 0 hidden)
+ = Active Route, - = Last Active, * = Both

10.10.10.0/29      *[BGP/170] 00:05:38, localpref 100, from 3.3.3.3
                      AS path: I, validation-state: unverified
                      to 13.13.13.2 via lt-0/0/0.13, label-switched-path R1-to-R3
                    > to 12.12.12.2 via lt-0/0/0.12, label-switched-path R1-to-R3-2

admin@vMX-1:R1>

 

 

 

Below the expected result I am not able to get  :

 

admin@vMX-1:R1> show route 10.10.10.1   
5_VRF.inet.0: 6 destinations, 10 routes (6 active, 0 holddown, 0 hidden)
+ = Active Route, - = Last Active, * = Both
10.10.10.0/29  [BGP/170] 00:05:33, localpref 100, from 4.4.4.4
                      AS path: I, validation-state: unverified
                      to 12.12.12.2 via lt-0/0/0.12, label-switched-path R1-to-R4-2

 

 

 

Please advise in what can bee done to malke the expected result happen...

4 REPLIES 4
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Junos

Re: Install next-hop LSP from a prefix advertised by multiple PE

‎12-01-2018 11:23 PM

Hello,

"install-lsp-nexthop" works only for equal-cost/equal-metric LSPs. You need to equalize the LSP metric from ingress LSR point of view.

Additionally, if R5 is VRF CE and R3+R4 are VRF PE, You need unique RD on R3+R4 and on R1+R3 You'd need "routing-instances routing-options multipath" knob.

HTH

Thx

Alex

 

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Juniper PS can design, test & build the network/part of the network as per Your requirements

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Junos

Re: Install next-hop LSP from a prefix advertised by multiple PE

[ Edited ]
‎12-02-2018 04:57 AM

Hello Alex, Thanks for your feedback.

 

The R5 can be consider as a CE.

 

I've applied your recommendations but it's still not working...

 

Recom applied : Routing instance 5_VRF routing option multipath in R1 and R3 along with same same RD 3.3.3.3:15 in R3+R4

 

I've attached the lab setup... Can you suggest the way to go with lsp metric option ?

 

Otherwise, in case the option I am following is not correct, what should be the way to achieve this setup ?

 

 

Attachments

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Junos

Re: Install next-hop LSP from a prefix advertised by multiple PE

‎12-02-2018 09:40 AM

+++ Logs

 

admin@vMX-1:R1> show route 10.10.10.3                

5_VRF.inet.0: 6 destinations, 12 routes (6 active, 0 holddown, 0 hidden)
@ = Routing Use Only, # = Forwarding Use Only
+ = Active Route, - = Last Active, * = Both

10.10.10.0/29      @[BGP/170] 00:01:54, localpref 100, from 3.3.3.3
                      AS path: I, validation-state: unverified
                      to 13.13.13.2 via lt-0/0/0.13, label-switched-path R1-to-R3
                    > to 12.12.12.2 via lt-0/0/0.12, label-switched-path R1-to-R3-2
                    [BGP/170] 00:00:04, localpref 100, from 4.4.4.4
                      AS path: I, validation-state: unverified
                      to 13.13.13.2 via lt-0/0/0.13, label-switched-path R1-to-R4
                   #[Multipath/255] 00:01:54, metric2 0
                      to 13.13.13.2 via lt-0/0/0.13, label-switched-path R1-to-R3
                      to 12.12.12.2 via lt-0/0/0.12, label-switched-path R1-to-R3-2
                      to 13.13.13.2 via lt-0/0/0.13, label-switched-path R1-to-R4

 

 

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Junos

Re: Install next-hop LSP from a prefix advertised by multiple PE

‎12-02-2018 10:59 PM

Hello,


@Ephs_NE wrote:

Hello Alex, Thanks for your feedback.

 

The R5 can be consider as a CE.

 

I've applied your recommendations but it's still not working...

 

Recom applied : Routing instance 5_VRF routing option multipath in R1 and R3 along with same same RD 3.3.3.3:15 in R3+R4

 

 


 You applied my recommendation incorrectly.

I told You to use unique RD on R3 and R4. "Unique" means R3' RD is not equal R4' RD and not equal any other RD in Your lab.

 


@Ephs_NE wrote:

 

I've attached the lab setup... Can you suggest the way to go with lsp metric option ?

 

 


You can assign static metric under "set protocols mpls label-switched-path BLAH"

HTH

Thx

Alex

_____________________________________________________________________

Please ask Your Juniper account team about Juniper Professional Services offerings.
Juniper PS can design, test & build the network/part of the network as per Your requirements

+++++++++++++++++++++++++++++++++++++++++++++

Accept as Solution = cool !
Accept as Solution+Kudo = You are a Star !
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