Cisco ASR 900 Series User Manual

Traffic loss is expected and acceptable until the restore LSP is signaled and established.Note
When the primary LSP recovers, traffic is automatically switched back to the primary LSP (make-before-break
scenario) and restore LSP is torn down. If the sticky option is configured in the path option, protect LSP can
recover before the primary LSP. In this case, traffic reverted to the protect LSP and the restore LSP is torn
down.
To enable restore LSP for a tunnel, configure the restore path option under the tunnel interface using the
command:
tunnel mpls traffic-eng path-option restore <index> [dynamic | explicit]
Multiple restore path options can be configured on a tunnel. However, only the restore path option with the
same index as the path option used by primary LSP is used for establishing the restore LSP. For example,
after primary and protect LSPs associated with the path option index X are administratively down, restore
LSP is signaled using the restore path option with index X, if it is configured. Else, no restore LSP is signaled.
Restore path option is supported for unidirectional, bidirectional co-routed, or non co-routed tunnels. It
is not supported for lockout, sticky, and non-revertive modes.
Note
Configuring the Restore Path Option
tunnel mpls traffic-eng path-option restore <index> [dynamic | explicit]
Router(config-if)# tunnel mpls traffic-eng path-option ?
<1-1000> preference for this path option
protect a path protection setup option
restore a path restore setup option
Verifying the Restore Path Option
The following is an example of the information displayed for the tunnel when restore LSP is carrying traffic:
Router# show mpls traffic-eng tunnels Tunnel 100
Name: iolA_t100 (Tunnel100) Destination: 192.168.1.4
Status:
Admin: up Oper: up Path: valid Signalling: connected
path restore option 1, type dynamic (Basis for Restore, path weight 40)
path option 1, (LOCKDOWN & STICKY) type dynamic
Path Protection: Requested
path protect option 1, (LOCKDOWN & STICKY) type diverse
Path Restore: Restore lsp in use.
path restore option 1, type dynamic (Basis for Restore, path weight 40)
Lockout Info:
Locked Out: No
Router# show running-config interface tunnel 1000
Building configuration...
Current configuration: 675 bytes
!
interface Tunnel1000
ip unnumbered Loopback0
tunnel mode mpls traffic-eng
tunnel destination 56.6.6.6
tunnel mpls traffic-eng autoroute announce
tunnel mpls traffic-eng priority 7 7
tunnel mpls traffic-eng bandwidth 200
tunnel mpls traffic-eng path-option 10 dynamic lockdown sticky
MPLS Basic Configuration Guide, Cisco IOS XE Everest 16.5.1 (Cisco ASR 900 Series)
164
Flex LSP Overview
Restore Path Option

Cisco ASR 900 Series Specifications

General

Brand	Cisco
Model	ASR 900 Series
Category	Network Router
Language	English