Technical Documentation

Configuring and Verifying Link Protection

The following sections describe the steps you must take to configure and verify link protection (many-to-one backup):

  1. Configure Link Protection
  2. Verify That Link Protection Is Up

Configure Link Protection

Purpose

Configuring link protection is a two-part process. The first part involves configuring link protection on the RSVP interface, and the second part sets link protection for any LSPs traversing the protected link that require use of the bypass path.

Action

To configure link protection, follow these steps:

  1. In configuration mode, go to the following hierarchy level:
    [edit]user@R1# edit protocols rsvp interface type-fpc/pic/port

    For example:

    [edit]user@R1# edit protocols rsvp interface fe-0/1/0
  2. Configure link protection for the interface:
    [edit protocols rsvp interface type-fpc/pic/port]user@R1# set link-protection
  3. Verify the link protection configuration for the interface:
    [edit protocols rsvp interface type-fpc/pic/port]user@R1# show
  4. Configure link protection for LSPs requiring use of the bypass path:
    [edit protocols rsvp interface fe-0/1/0.0]user@R1# top [edit]user@R1# edit protocols mpls label-switched-path lsp-path-name

    For example:

    [edit]user@R1# edit protocols mpls label-switched-path lsp2-r1-to-r5
  5. Configure link protection for the LSP:
    [edit protocols mpls label-switched-path lsp-path-name]user@R1# set link-protection
  6. Verify and the link protection configuration for the LSP:
    [edit protocols mpls label-switched-path lsp-path-name]user@R1# show user@R1# commit

Sample Output

The following sample output illustrates the configuration of the link protection on ingress router R1 in the network shown in Many-to-One or Link Protection:

[edit protocols rsvp]
user@R1# show 
interface fe-0/1/0.0 {
     link-protection; #Protection for the RSVP interface 
}

[edit protocols mpls label-switched-path lsp2-r1-to-r5]
user@R1# up 

[edit protocols mpls]
user@R1# show 
label-switched-path lsp2-r1-to-r5  { #Path level of the hierarchy
    #to 192.168.5.1;
    link-protection;

[edit protocols mpls]
user@R1# commit  
commit complete

Meaning

The sample output shows link protection for a specific interface. After link protection is configured, a bypass path is signaled to avoid that link in case of a failure. Having a bypass path available does not in itself provide protection for LSPs that traverse the protected link. You must configure link protection on the ingress router for each LSP that will benefit from the bypass path.


Verify That Link Protection Is Up

Purpose

When you verify link protection, you must check that the bypass LSP is up. You can also check the number of LSPs protected by the bypass. In the network shown in Many-to-One or Link Protection, a bypass path should be up to protect the link between R1 and R2, or next-hop 10.0.12.14, and the two LSPs traversing the link, lsp2-r1-to-r5 and lsp1-r6-to-r0.

Action

To verify link protection (many-to-one backup), enter the following JUNOS CLI operational mode commands on the ingress router:

user@host> show mpls lsp extensive user@host> show rsvp session detail user@host> show rsvp interface

Sample Output

user@R1> show mpls lsp extensive | no-more 
Ingress LSP: 1 sessions

192.168.5.1
  From: 192.168.1.1, State: Up, ActiveRoute: 0, LSPname: lsp2-r1-to-r5
  ActivePath:  via-r2 (primary)
   Link protection desired
  LoadBalance: Random
  Encoding type: Packet, Switching type: Packet, GPID: IPv4
 *Primary   via-r2           State: Up
    SmartOptimizeTimer: 180
    Computed ERO (S [L] denotes strict [loose] hops): (CSPF metric: 3)
 10.0.12.14 S 10.0.24.2 S 10.0.45.2 S 
     Received RRO (ProtectionFlag 1=Available 2=InUse 4=B/W 8=Node  10=SoftPreempt):
          10.0.12.14(Label=101264) 10.0.24.2(Label=100736) 10.0.45.2(Label=3)
    6 Jun 16 14:06:33  Link-protection Up
    5 Jun 16 14:05:39 Selected as active path
    4 Jun 16 14:05:39 Record Route:  10.0.12.14(Label=101264) 10.0.24.2(Label=100736) 10.0.45.2(Label=3)
    3 Jun 16 14:05:39 Up
    2 Jun 16 14:05:39 Originate Call
    1 Jun 16 14:05:39 CSPF: computation result accepted
  Created: Fri Jun 16 14:05:38 2006
Total 1 displayed, Up 1, Down 0

[...Output truncated...]

Transit LSP: 2 sessions

192.168.0.1
  From: 192.168.6.1, LSPstate: Up, ActiveRoute: 0
   LSPname: lsp1-r6-to-r0, LSPpath: Primary
  Suggested label received: -, Suggested label sent: -
  Recovery label received: -, Recovery label sent: 101296
  Resv style: 1 SE, Label in: 100192, Label out: 101296
  Time left:  116, Since: Mon Jun 19 10:26:32 2006
  Tspec: rate 0bps size 0bps peak Infbps m 20 M 1500
  Port number: sender 1 receiver 58739 protocol 0
  Link protection desired
  Type: Link protected LSP, using Bypass->10.0.12.14
      1 Jun 19 10:26:32 Link protection up, using Bypass->10.0.12.14
  PATH rcvfrom: 10.0.16.2 (so-0/0/3.0) 579 pkts
  Adspec: received MTU 1500 sent MTU 1500
  PATH sentto: 10.0.12.14 (fe-0/1/0.0) 474 pkts
  RESV rcvfrom: 10.0.12.14 (fe-0/1/0.0) 501 pkts
  Explct route: 10.0.12.14 10.0.24.2 10.0.45.2 10.0.50.2 
  Record route: 10.0.16.2 <self> 10.0.12.14 10.0.24.2 10.0.45.2 10.0.50.2 
[...Output truncated...]

Meaning

The sample output from ingress router R1 shows that lsp2-r1-to-r5 and lsp1-r6-to-r0 have link protection up, and both LSPs are using the bypass path, 10.0.12.14. However, the show mpls lsp command does not list the bypass path. For information about the bypass path, use the show rsvp session command.

Sample Output

user@R1> show rsvp session detail 
Ingress RSVP: 2 sessions
192.168.2.1
  From: 192.168.1.1, LSPstate: Up, ActiveRoute: 0
   LSPname: Bypass->10.0.12.14
  Suggested label received: -, Suggested label sent: -
  Recovery label received: -, Recovery label sent: 101456
  Resv style: 1 SE, Label in: -, Label out: 101456
  Time left:    -, Since: Fri May 26 18:38:09 2006
  Tspec: rate 0bps size 0bps peak Infbps m 20 M 1500
  Port number: sender 1 receiver 18709 protocol 0
   Type: Bypass LSP
     Number of data route tunnel through: 2
    Number of RSVP session tunnel through: 0
  PATH rcvfrom: localclient 
  Adspec: sent MTU 1500
  Path MTU: received 1500
  PATH sentto: 10.0.17.14 (fe-0/1/1.0) 51939 pkts
  RESV rcvfrom: 10.0.17.14 (fe-0/1/1.0) 55095 pkts
   Explct route: 10.0.17.14 10.0.27.1 
  Record route: <self> 10.0.17.14 10.0.27.1  

192.168.5.1
  From: 192.168.1.1, LSPstate: Up, ActiveRoute: 0
  LSPname: lsp2-r1-to-r5, LSPpath: Primary
  Suggested label received: -, Suggested label sent: -
  Recovery label received: -, Recovery label sent: 101264
  Resv style: 1 SE, Label in: -, Label out: 101264
  Time left:    -, Since: Fri Jun 16 14:05:39 2006
  Tspec: rate 0bps size 0bps peak Infbps m 20 M 1500
  Port number: sender 1 receiver 18724 protocol 0
  Link protection desired
  Type: Link protected LSP
  PATH rcvfrom: localclient 
  Adspec: sent MTU 1500
  Path MTU: received 1500
  PATH sentto: 10.0.12.14 (fe-0/1/0.0) 8477 pkts
  RESV rcvfrom: 10.0.12.14 (fe-0/1/0.0) 8992 pkts
  Explct route: 10.0.12.14 10.0.24.2 10.0.45.2 
  Record route: <self> 10.0.12.14 10.0.24.2 10.0.45.2  
Total 2 displayed, Up 2, Down 0

Egress RSVP: 1 sessions

192.168.1.1
  From: 192.168.5.1, LSPstate: Up, ActiveRoute: 0
  LSPname: r5-to-r1, LSPpath: Primary
  Suggested label received: -, Suggested label sent: -
  Recovery label received: -, Recovery label sent: -
  Resv style: 1 FF, Label in: 3, Label out: -
  Time left:  159, Since: Mon May 22 22:08:16 2006
  Tspec: rate 0bps size 0bps peak Infbps m 20 M 1500
  Port number: sender 1 receiver 64449 protocol 0
  PATH rcvfrom: 10.0.17.14 (fe-0/1/1.0) 63145 pkts
  Adspec: received MTU 1500 
  PATH sentto: localclient
  RESV rcvfrom: localclient 
  Record route: 10.0.59.1 10.0.79.2 10.0.17.14 <self>  
Total 1 displayed, Up 1, Down 0
Transit RSVP: 2 sessions
192.168.0.1
  From: 192.168.6.1, LSPstate: Up, ActiveRoute: 0
  LSPname: lsp1-r6-to-r0, LSPpath: Primary
  Suggested label received: -, Suggested label sent: -
  Recovery label received: -, Recovery label sent: 101296
  Resv style: 1 SE, Label in: 100192, Label out: 101296
  Time left:  129, Since: Mon Jun 19 10:26:32 2006
  Tspec: rate 0bps size 0bps peak Infbps m 20 M 1500
  Port number: sender 1 receiver 58739 protocol 0
  Link protection desired
  Type: Link protected LSP
  PATH rcvfrom: 10.0.16.2 (so-0/0/3.0) 3128 pkts
  Adspec: received MTU 1500 sent MTU 1500
  PATH sentto: 10.0.12.14 (fe-0/1/0.0) 2533 pkts
  RESV rcvfrom: 10.0.12.14 (fe-0/1/0.0) 2685 pkts
  Explct route: 10.0.12.14 10.0.24.2 10.0.45.2 10.0.50.2 
  Record route: 10.0.16.2 <self> 10.0.12.14 10.0.24.2 10.0.45.2 10.0.50.2  

192.168.6.1
  From: 192.168.0.1, LSPstate: Up, ActiveRoute: 0
  LSPname: r0-to-r6, LSPpath: Primary
  Suggested label received: -, Suggested label sent: -
  Recovery label received: -, Recovery label sent: 3
  Resv style: 1 FF, Label in: 100128, Label out: 3
  Time left:  143, Since: Thu May 25 12:30:26 2006
  Tspec: rate 0bps size 0bps peak Infbps m 20 M 1500
  Port number: sender 1 receiver 4111 protocol 0
  PATH rcvfrom: 10.0.17.14 (fe-0/1/1.0) 57716 pkts
  Adspec: received MTU 1500 sent MTU 1500
  PATH sentto: 10.0.16.2 (so-0/0/3.0) 54524 pkts
  RESV rcvfrom: 10.0.16.2 (so-0/0/3.0) 50534 pkts
  Explct route: 10.0.16.2 
  Record route: 10.0.50.2 10.0.59.1 10.0.79.2 10.0.17.14 <self> 10.0.16.2  
Total 2 displayed, Up 2, Down 0

Meaning

The sample output from ingress router R1 shows the ingress, egress, and transit LSPs for R1. Some information is similar to that found in the show mpls lsp command. However, because link protection is an RSVP feature, information about bypass paths is provided. The bypass path appears as a separate RSVP ingress session for the protected interface, as indicated by the Type field.

The bypass path name is automatically generated. By default, the name appears as Bypass > interface-address, where the interface address is the next downstream router’s interface (10.0.12.14). The explicit route 10.0.17.14 10.0.27.1 for the session shows R7 as the transit node and R2 as the egress node.

Within the ingress RSVP section of the output, the LSP originating at R1 (lsp2-r1-to-r5) is shown requesting link protection. Since a bypass path is in place to protect the downstream link, lsp2-r1-to-r5 is associated with the bypass, as indicated by the Link protected LSP field.

The egress section of the output shows the return LSP r5-to-r1, which is not protected.

The transit section of the output shows link protection requested by lsp1-r6-to-r0. Since a bypass path is in place to protect the downstream link, lsp1-r6-to-r0 is associated with the bypass, as indicated by the Link protected LSP field. Also included in the transit section of the output is the return LSP r0-to-r6, which is not protected.

Sample Output

user@R1> show rsvp interface 
RSVP interface: 4 active
                  Active Subscr- Static      Available   Reserved    Highwater
Interface   State resv   iption  BW          BW          BW          mark
fe-0/1/0.0  Up          2    100%  100Mbps     100Mbps     0bps        35Mbps
fe-0/1/1.0  Up          1    100%  100Mbps     100Mbps     0bps        0bps
fe-0/1/2.0  Up          0    100%  100Mbps     100Mbps     0bps        0bps
so-0/0/3.0  Up          1    100%  155.52Mbps  155.52Mbps  0bps        0bps

Meaning

The sample output from ingress router R1 shows the number of LSPs going through the interfaces configured on R1. The Active resv field shows the number of LSPs for each interface. For example, interface fe-0/1/0.0 between R1 and R2 has two active reservations, lsp1-r6-to-r0 and lsp2-r1-to-r5; interface fe-0/1/1.0 between R1 and R7 has one, the bypass (10.0.12.14); interface fe-0/1/2.0 between R6 and R1 has no LSP reservations; and interface so-0/0/3.0 between R6 and R1 has one LSP reservation, lsp1-r6-to-r0.


Published: 2010-01-30