Example for Configure a Hot-standby CR-LSP
Networking Requirements
Figure 1 illustrates an MPLS VPN network. A TE tunnel is established from PE1 to PE2. A hot-standby CR-LSP and a best-effort path are configured. The networking is as follows:
The primary CR-LSP is along the path PE1 -> P1 -> PE2.
The hot-standby CR-LSP is along the path PE1 -> P2 -> PE2.
If the primary CR-LSP fails, traffic switches to the backup CR-LSP. After the primary CR-LSP recovers, traffic switches back to the primary CR-LSP after a 15-second delay. If both the primary and backup CR-LSPs fail, traffic switches to the best-effort path. Explicit paths can be configured for the primary and backup CR-LSPs. A best-effort path can be generated automatically. In this example, the best-effort path is PE1 -> P2 -> P1 -> PE2. The calculated best-effort path varies according to the faulty node.
Configuration Roadmap
The configuration roadmap is as follows:
Assign an IP address to every interface and configure an IGP to implement connectivity.
Configure basic MPLS and MPLS TE functions.
Configure explicit paths on PE1 for the primary and hot-standby CR-LSPs.
Create a tunnel destined for PE2; specify explicit paths; enable hot standby; configure a best-effort path; set the switchback delay time to 15 seconds on PE1.
Data Preparation
To complete the configuration, you need the following data:
IGP type and data
MPLS LSR IDs
Tunnel interface number and bandwidth
Explicit paths for the primary and hot-standby CR-LSPs
Procedure
- Assign an IP address and its mask to every interface.
Assign an IP address and its mask to every interface and configure a loopback interface address as an LSR ID on every node. For configuration details, see Configuration Files in this section.
- Configure an IGP.
Configure OSPF or IS-IS on every node to implement connectivity between them. IS-IS is used in this example. For configuration details, see Configuration Files in this section.
- Configure basic MPLS functions.
Set an LSR ID in the system view, and enable MPLS in the system and interface views on every node. For configuration details, see Configuration Files in this section.
- Configure basic MPLS TE functions.
Enable MPLS TE and RSVP-TE in the MPLS and interface views on every node. For configuration details, see Configuration Files in this section.
- Configure IS-IS TE and CSPF.
Configure IS-IS TE on all nodes and enable CSPF on PE1. For configuration details, see Configuring an RSVP-TE Tunnel.
- Configure explicit paths for the primary and hot-standby CR-LSPs.
# Configure an explicit path for the primary CR-LSP on PE1.
<PE1> system-view [~PE1] explicit-path main [*PE1-explicit-path-main] next hop 10.4.1.2 [*PE1-explicit-path-main] next hop 10.2.1.2 [*PE1-explicit-path-main] next hop 3.3.3.3 [*PE1-explicit-path-main] quit
# Configure an explicit path for the hot-standby CR-LSP on PE1.
[*PE1] explicit-path backup [*PE1-explicit-path-backup] next hop 10.3.1.2 [*PE1-explicit-path-backup] next hop 10.5.1.2 [*PE1-explicit-path-backup] next hop 3.3.3.3 [*PE1-explicit-path-backup] commit [~PE1-explicit-path-backup] quit
# After completing the configurations, run the display explicit-path main command on PE1. Information about the explicit paths for the primary and hot-standby CR-LSPs is displayed.
[~PE1] display explicit-path main Path Name : main Path Status : Enabled 1 10.4.1.2 Strict Include 2 10.2.1.2 Strict Include 3 3.3.3.3 Strict Include [~PE1] display explicit-path backup Path Name : backup Path Status : Enabled 1 10.3.1.2 Strict Include 2 10.5.1.2 Strict Include 3 3.3.3.3 Strict Include
- Configure tunnel interfaces.
# Create a tunnel interface on PE1 and specify an explicit path on PE1.
[~PE1] interface tunnel1 [*PE1-Tunnel1] ip address unnumbered interface loopback 1 [*PE1-Tunnel1] tunnel-protocol mpls te [*PE1-Tunnel1] destination 3.3.3.3 [*PE1-Tunnel1] mpls te tunnel-id 502 [*PE1-Tunnel1] mpls te path explicit-path main
# Configure hot standby on the tunnel interface; set the switchback delay time to 15 seconds; specify an explicit path; configure a best-effort path.
[*PE1-Tunnel1] mpls te backup hot-standby mode revertive wtr 15 [*PE1-Tunnel1] mpls te path explicit-path backup secondary [*PE1-Tunnel1] mpls te backup ordinary best-effort [*PE1-Tunnel1] commit [~PE1-Tunnel1] quit
After completing the configurations, run the display mpls te tunnel-interface tunnel1 command on PE1. Both the primary and hot-standby CR-LSPs have been established.
[~PE1] display mpls te tunnel-interface tunnel1 Tunnel Name : Tunnel1 Signalled Tunnel Name: - Tunnel State Desc : Primary CR-LSP Up and HotBackup CR-LSP Up Tunnel Attributes : Active LSP : Primary LSP Traffic Switch : - Session ID : 502 Ingress LSR ID : 4.4.4.4 Egress LSR ID: 3.3.3.3 Admin State : UP Oper State : UP Signaling Protocol : RSVP FTid : 161 Tie-Breaking Policy : None Metric Type : None Bfd Cap : None Reopt : Disabled Reopt Freq : - Inter-area Reopt : Disabled Auto BW : Disabled Threshold : 0 percent Current Collected BW: 0 kbps Auto BW Freq : 0 Min BW : 0 kbps Max BW : 0 kbps Offload : Disabled Offload Freq : - Low Value : - High Value : - Readjust Value : - Offload Explicit Path Name: - Tunnel Group : - Interfaces Protected: - Excluded IP Address : - Referred LSP Count : 0 Primary Tunnel : - Pri Tunn Sum : - Backup Tunnel : - Group Status : - Oam Status : - IPTN InLabel : - Tunnel BFD Status : - BackUp LSP Type : Hot-Standby BestEffort : Enabled Secondary HopLimit : 32 BestEffort HopLimit : - Secondary Explicit Path Name: backup Secondary Affinity Prop/Mask: 0x0/0x0 BestEffort Affinity Prop/Mask: 0x0/0x0 IsConfigLspConstraint: - Hot-Standby Revertive Mode: Revertive Hot-Standby Overlap-path: Disabled Hot-Standby Switch State: CLEAR Bit Error Detection: Disabled Bit Error Detection Switch Threshold: - Bit Error Detection Resume Threshold: - Ip-Prefix Name : - P2p-Template Name : - PCE Delegate : No LSP Control Status : Local control Path Verification : -- Entropy Label : None Associated Tunnel Group ID: - Associated Tunnel Group Type: - Auto BW Remain Time : 200 s Reopt Remain Time : 100 s Metric Inherit IGP : None Binding Sid : - Reverse Binding Sid : - Self-Ping : Disable Self-Ping Duration : 1800 sec FRR Attr Source : - Is FRR degrade down : - Primary LSP ID : 4.4.4.4:424 LSP State : UP LSP Type : Primary Setup Priority : 7 Hold Priority: 7 IncludeAll : 0x0 IncludeAny : 0x0 ExcludeAny : 0x0 Affinity Prop/Mask : 0x0/0x0 Resv Style : SE Configured Bandwidth Information: CT0 Bandwidth(Kbit/sec): 10000 CT1 Bandwidth(Kbit/sec): 0 CT2 Bandwidth(Kbit/sec): 0 CT3 Bandwidth(Kbit/sec): 0 CT4 Bandwidth(Kbit/sec): 0 CT5 Bandwidth(Kbit/sec): 0 CT6 Bandwidth(Kbit/sec): 0 CT7 Bandwidth(Kbit/sec): 0 Actual Bandwidth Information: CT0 Bandwidth(Kbit/sec): 10000 CT1 Bandwidth(Kbit/sec): 0 CT2 Bandwidth(Kbit/sec): 0 CT3 Bandwidth(Kbit/sec): 0 CT4 Bandwidth(Kbit/sec): 0 CT5 Bandwidth(Kbit/sec): 0 CT6 Bandwidth(Kbit/sec): 0 CT7 Bandwidth(Kbit/sec): 0 Explicit Path Name : main Hop Limit: 32 Record Route : Enabled Record Label : Disabled Route Pinning : Disabled FRR Flag : Disabled IdleTime Remain : - BFD Status : - Soft Preemption : Enabled Reroute Flag : Disabled Pce Flag : Normal Path Setup Type : EXPLICIT Create Modify LSP Reason: - Self-Ping Status : - Backup LSP ID : 4.4.4.4:423 IsBestEffortPath : No LSP State : UP LSP Type : Hot-Standby Setup Priority : 7 Hold Priority: 7 IncludeAll : 0x0 IncludeAny : 0x0 ExcludeAny : 0x0 Affinity Prop/Mask : 0x0/0x0 Resv Style : SE Configured Bandwidth Information: CT0 Bandwidth(Kbit/sec): 10000 CT1 Bandwidth(Kbit/sec): 0 CT2 Bandwidth(Kbit/sec): 0 CT3 Bandwidth(Kbit/sec): 0 CT4 Bandwidth(Kbit/sec): 0 CT5 Bandwidth(Kbit/sec): 0 CT6 Bandwidth(Kbit/sec): 0 CT7 Bandwidth(Kbit/sec): 0 Actual Bandwidth Information: CT0 Bandwidth(Kbit/sec): 10000 CT1 Bandwidth(Kbit/sec): 0 CT2 Bandwidth(Kbit/sec): 0 CT3 Bandwidth(Kbit/sec): 0 CT4 Bandwidth(Kbit/sec): 0 CT5 Bandwidth(Kbit/sec): 0 CT6 Bandwidth(Kbit/sec): 0 CT7 Bandwidth(Kbit/sec): 0 Explicit Path Name : backup Hop Limit: 32 Record Route : Enabled Record Label : Disabled Route Pinning : Disabled FRR Flag : Disabled IdleTime Remain : - BFD Status : - Soft Preemption : Enabled Reroute Flag : Disabled Pce Flag : Normal Path Setup Type : EXPLICIT Create Modify LSP Reason: - Self-Ping Status : -
# Run the display mpls te hot-standby state command on PE1. Hot standby information is displayed.
[~PE1] display mpls te hot-standby state interface Tunnel1 ---------------------------------------------------------------- Verbose information about the Tunnel1 hot-standby state ---------------------------------------------------------------- Tunnel Name : Tunnel1 Session ID : 502 Main LSP index : 0xC1 Hot-Standby LSP index : 0xE1 HSB switch result : main LSP HSB switch reason : - WTR config time : 15 s WTR remain time : - Using overlapped path : no
# Run the ping lsp te command. The hot-standby CR-LSP is reachable.[~PE1] ping lsp te tunnel1 hot-standby LSP PING FEC: RSVP IPV4 SESSION QUERY Tunnel1 : 100 data bytes, press CTR L_C to break Reply from 3.3.3.3: bytes=100 Sequence=1 time = 4 ms Reply from 3.3.3.3: bytes=100 Sequence=2 time = 3 ms Reply from 3.3.3.3: bytes=100 Sequence=3 time = 3 ms Reply from 3.3.3.3: bytes=100 Sequence=4 time = 3 ms Reply from 3.3.3.3: bytes=100 Sequence=5 time = 6 ms --- FEC: RSVP IPV4 SESSION QUERY Tunnel1 ping statistics --- 5 packet(s) transmitted 5 packet(s) received 0.00% packet loss round-trip min/avg/max = 3/3/6 ms# Run the tracert lsp te command on PE1. The path for the hot-standby CR-LSP is reachable.[~PE1] tracert lsp te tunnel1 hot-standby LSP Trace Route FEC: TE TUNNEL IPV4 SESSION QUERY Tunnel1 , press CTRL_C to break. TTL Replier Time Type Downstream 0 Ingress 10.3.1.2/[13313 ] 1 10.3.1.2 90 ms Transit 10.5.1.2/[3 ] 2 3.3.3.3 130 ms Egress - Verify the configuration.
Connect port 1 and port 2 on a tester to PE1 and PE2, respectively. Set correct label values. Inject traffic destined for port 2 into port 1. After the cable is removed from GE 0/1/8 on PE1 or GE 0/1/8 on P1, traffic is restored within milliseconds. Run the display mpls te hot-standby state interface tunnel1 command on PE1. Traffic has switched to the hot-standby CR-LSP.
[~PE1] display mpls te hot-standby state interface tunnel1 ---------------------------------------------------------------- Verbose information about the Tunnel1 hot-standby state ---------------------------------------------------------------- Tunnel Name : Tunnel1 Session ID : 502 Main LSP index : 0x0 Hot-Standby LSP index : 0xE1 HSB switch result : hot-standby LSP HSB switch reason : signal fail WTR config time : 10 s WTR remain time : - Using overlapped path : no
Insert the cable into GE 0/1/8 and wait 15 seconds. Traffic switches back to the primary CR-LSP.
If the cables to GE 0/1/8 on PE1 (or GE 0/1/8 on P1) and GE 0/1/8 on PE2 (or GE 0/1/8 on P2) are removed, the tunnel interface goes Down and then Up. A best-effort path is established and takes over traffic.
[~PE1] display mpls te tunnel-interface tunnel1 Tunnel Name : Tunnel1 Signalled Tunnel Name: - Tunnel State Desc : Backup CR-LSP In use and Primary CR-LSP setting Up Tunnel Attributes : Active LSP : BestEffort LSP Traffic Switch : - Session ID : 502 Ingress LSR ID : 4.4.4.4 Egress LSR ID: 3.3.3.3 Admin State : UP Oper State : UP Signaling Protocol : RSVP FTid : 161 Tie-Breaking Policy : None Metric Type : None Bfd Cap : None Reopt : Disabled Reopt Freq : - Inter-area Reopt : Disabled Auto BW : Disabled Threshold : 0 percent Current Collected BW: 0 kbps Auto BW Freq : 0 Min BW : 0 kbps Max BW : 0 kbps Offload : Disabled Offload Freq : 0 sec Low Value : 0 kbps High Value : 0 kbps Readjust Value : 0 kbps Offload Explicit Path Name: - Tunnel Group : - Interfaces Protected: - Excluded IP Address : - Referred LSP Count : 0 Primary Tunnel : - Pri Tunn Sum : - Backup Tunnel : - Group Status : - Oam Status : - IPTN InLabel : - Tunnel BFD Status : - BackUp LSP Type : BestEffort BestEffort : Enabled Secondary HopLimit : 32 BestEffort HopLimit : - Secondary Explicit Path Name: backup Secondary Affinity Prop/Mask: 0x0/0x0 BestEffort Affinity Prop/Mask: 0x0/0x0 IsConfigLspConstraint: - Hot-Standby Revertive Mode: Revertive Hot-Standby Overlap-path: Disabled Hot-Standby Switch State: CLEAR Bit Error Detection: Disabled Bit Error Detection Switch Threshold: - Bit Error Detection Resume Threshold: - Ip-Prefix Name : - P2p-Template Name : - PCE Delegate : No LSP Control Status : Local control Path Verification : -- Entropy Label : None Associated Tunnel Group ID: - Associated Tunnel Group Type: - Auto BW Remain Time : 200 s Reopt Remain Time : 100 s Metric Inherit IGP : None Binding Sid : - Reverse Binding Sid : - Self-Ping : Disable Self-Ping Duration : 1800 sec FRR Attr Source : - Is FRR degrade down : No Primary LSP ID : 4.4.4.4:436 LSP State : DOWN LSP Type : Primary Setup Priority : 7 Hold Priority: 7 IncludeAll : 0x0 IncludeAny : 0x0 ExcludeAny : 0x0 Affinity Prop/Mask : 0x0/0x0 Resv Style : SE Configured Bandwidth Information: CT0 Bandwidth(Kbit/sec): 10000 CT1 Bandwidth(Kbit/sec): 0 CT2 Bandwidth(Kbit/sec): 0 CT3 Bandwidth(Kbit/sec): 0 CT4 Bandwidth(Kbit/sec): 0 CT5 Bandwidth(Kbit/sec): 0 CT6 Bandwidth(Kbit/sec): 0 CT7 Bandwidth(Kbit/sec): 0 Actual Bandwidth Information: CT0 Bandwidth(Kbit/sec): 10000 CT1 Bandwidth(Kbit/sec): 0 CT2 Bandwidth(Kbit/sec): 0 CT3 Bandwidth(Kbit/sec): 0 CT4 Bandwidth(Kbit/sec): 0 CT5 Bandwidth(Kbit/sec): 0 CT6 Bandwidth(Kbit/sec): 0 CT7 Bandwidth(Kbit/sec): 0 Explicit Path Name : main Hop Limit: 32 Record Route : Enabled Record Label : Disabled Route Pinning : Disabled FRR Flag : Disabled IdleTime Remain : - BFD Status : - Soft Preemption : Enabled Reroute Flag : Disabled Pce Flag : Normal Path Setup Type : EXPLICIT Create Modify LSP Reason: - Self-Ping Status : - Backup LSP ID : 4.4.4.4:440 IsBestEffortPath : No LSP State : DOWN LSP Type : Hot-Standby Setup Priority : 7 Hold Priority: 7 IncludeAll : 0x0 IncludeAny : 0x0 ExcludeAny : 0x0 Affinity Prop/Mask : 0x0/0x0 Resv Style : SE Configured Bandwidth Information: CT0 Bandwidth(Kbit/sec): 10000 CT1 Bandwidth(Kbit/sec): 0 CT2 Bandwidth(Kbit/sec): 0 CT3 Bandwidth(Kbit/sec): 0 CT4 Bandwidth(Kbit/sec): 0 CT5 Bandwidth(Kbit/sec): 0 CT6 Bandwidth(Kbit/sec): 0 CT7 Bandwidth(Kbit/sec): 0 Actual Bandwidth Information: CT0 Bandwidth(Kbit/sec): 10000 CT1 Bandwidth(Kbit/sec): 0 CT2 Bandwidth(Kbit/sec): 0 CT3 Bandwidth(Kbit/sec): 0 CT4 Bandwidth(Kbit/sec): 0 CT5 Bandwidth(Kbit/sec): 0 CT6 Bandwidth(Kbit/sec): 0 CT7 Bandwidth(Kbit/sec): 0 Explicit Path Name : backup Hop Limit: 32 Record Route : Enabled Record Label : Disabled Route Pinning : Disabled FRR Flag : Disabled IdleTime Remain : - BFD Status : - Soft Preemption : Enabled Reroute Flag : Disabled Pce Flag : Normal Path Setup Type : EXPLICIT Create Modify LSP Reason: - Self-Ping Status : - Backup LSP ID : 4.4.4.4:439 IsBestEffortPath : Yes LSP State : UP LSP Type : BestEffort Setup Priority : 7 Hold Priority: 7 IncludeAll : 0x0 IncludeAny : 0x0 ExcludeAny : 0x0 Affinity Prop/Mask : 0x0/0x0 Resv Style : SE Configured Bandwidth Information: CT0 Bandwidth(Kbit/sec): 0 CT1 Bandwidth(Kbit/sec): 0 CT2 Bandwidth(Kbit/sec): 0 CT3 Bandwidth(Kbit/sec): 0 CT4 Bandwidth(Kbit/sec): 0 CT5 Bandwidth(Kbit/sec): 0 CT6 Bandwidth(Kbit/sec): 0 CT7 Bandwidth(Kbit/sec): 0 Actual Bandwidth Information: CT0 Bandwidth(Kbit/sec): 0 CT1 Bandwidth(Kbit/sec): 0 CT2 Bandwidth(Kbit/sec): 0 CT3 Bandwidth(Kbit/sec): 0 CT4 Bandwidth(Kbit/sec): 0 CT5 Bandwidth(Kbit/sec): 0 CT6 Bandwidth(Kbit/sec): 0 CT7 Bandwidth(Kbit/sec): 0 Explicit Path Name : - Hop Limit: - Record Route : Enabled Record Label : Disabled Route Pinning : Disabled FRR Flag : Disabled IdleTime Remain : - BFD Status : - Soft Preemption : Enabled Reroute Flag : Disabled Pce Flag : Normal Path Setup Type : CSPF Create Modify LSP Reason: - Self-Ping Status : - [~PE1] display mpls te tunnel path Tunnel Interface Name : Tunnel1 Lsp ID : 4.4.4.4 :502 :32776 Hop Information Hop 0 10.3.1.1 Hop 1 10.3.1.2 Hop 2 2.2.2.2 Hop 3 10.1.1.2 Hop 4 10.1.1.1 Hop 5 1.1.1.1 Hop 6 10.2.1.1 Hop 7 10.2.1.2 Hop 8 3.3.3.3
Configuration Files
PE1 configuration file
# sysname PE1 # mpls lsr-id 4.4.4.4 # mpls mpls te mpls te cspf mpls rsvp-te # explicit-path backup next hop 10.3.1.2 next hop 10.5.1.2 next hop 3.3.3.3 # explicit-path main next hop 10.4.1.2 next hop 10.2.1.2 next hop 3.3.3.3 # isis 1 cost-style wide traffic-eng level-1-2 network-entity 10.0000.0000.0004.00 # interface GigabitEthernet0/1/0 undo shutdown ip address 10.3.1.1 255.255.255.252 mpls mpls te isis enable 1 mpls rsvp-te # interface GigabitEthernet0/1/8 undo shutdown ip address 10.4.1.1 255.255.255.252 mpls mpls te isis enable 1 mpls rsvp-te # interface LoopBack1 ip address 4.4.4.4 255.255.255.255 isis enable 1 # interface Tunnel1 ip address unnumbered interface LoopBack1 tunnel-protocol mpls te destination 3.3.3.3 mpls te tunnel-id 502 mpls te record-route mpls te backup hot-standby mode revertive wtr 15 mpls te backup ordinary best-effort mpls te path explicit-path main mpls te path explicit-path backup secondary # return
P1 configuration file
# sysname P1 # mpls lsr-id 1.1.1.1 # mpls mpls te mpls rsvp-te # isis 1 cost-style wide traffic-eng level-1-2 network-entity 10.0000.0000.0001.00 # interface GigabitEthernet0/1/0 undo shutdown ip address 10.1.1.1 255.255.255.252 mpls mpls te isis enable 1 mpls rsvp-te # interface GigabitEthernet0/1/8 undo shutdown ip address 10.4.1.2 255.255.255.252 mpls mpls te isis enable 1 mpls rsvp-te # interface GigabitEthernet0/1/16 undo shutdown ip address 10.2.1.1 255.255.255.252 mpls mpls te isis enable 1 mpls rsvp-te # interface LoopBack1 isis enable 1 ip address 1.1.1.1 255.255.255.255 # return
P2 configuration file
# sysname P2 # mpls lsr-id 2.2.2.2 # mpls mpls te mpls rsvp-te # isis 1 cost-style wide traffic-eng level-1-2 network-entity 10.0000.0000.0002.00 # interface GigabitEthernet0/1/0 undo shutdown ip address 10.1.1.2 255.255.255.252 mpls mpls te isis enable 1 mpls rsvp-te # interface GigabitEthernet0/1/8 undo shutdown ip address 10.5.1.1 255.255.255.252 mpls mpls te isis enable 1 mpls rsvp-te # interface GigabitEthernet0/1/16 undo shutdown ip address 10.3.1.2 255.255.255.252 mpls mpls te isis enable 1 mpls rsvp-te # interface LoopBack1 ip address 2.2.2.2 255.255.255.255 isis enable 1 # return
PE2 configuration file
# sysname PE2 # mpls lsr-id 3.3.3.3 # mpls mpls te mpls rsvp-te # isis 1 cost-style wide traffic-eng level-1-2 network-entity 10.0000.0000.0003.00 # interface GigabitEthernet0/1/0 undo shutdown ip address 10.2.1.2 255.255.255.252 mpls mpls te isis enable 1 mpls rsvp-te # interface GigabitEthernet0/1/8 undo shutdown ip address 10.5.1.2 255.255.255.252 mpls mpls te isis enable 1 mpls rsvp-te # interface LoopBack1 ip address 3.3.3.3 255.255.255.255 isis enable 1 # return