Mpls-Te And Fast Reroute Over Link Bundles - Cisco ASR 9000 Series Configuration Manual

Implementing MPLS Traffic Engineering
When you configure TE tunnel with multiple protection on its path and merge point is the same node for
Note
more than one protection, you must configure record-route for that tunnel.
Related Topics
Protecting MPLS Tunnels with Fast Reroute, on page 162

MPLS-TE and Fast Reroute over Link Bundles

MPLS Traffic Engineering (TE) and Fast Reroute (FRR) are supported over bundle interfaces and virtual
local area network (VLAN) interfaces. Bidirectional forwarding detection (BFD) over VLAN is used as an
FRR trigger to obtain less than 50 milliseconds of switchover time.
These link bundle types are supported for MPLS-TE/FRR:
• Over Ethernet link bundles.
• Over VLANs over Ethernet link bundles.
• Number of links are limited to 100 for MPLS-TE and FRR.
• VLANs go over any Ethernet interface (for example, GigabitEthernet and TenGigE).
FRR is supported over bundle interfaces in the following ways:
• Uses minimum links as a threshold to trigger FRR over a bundle interface.
• Uses the minimum total available bandwidth as a threshold to trigger FRR.
Ignore Intermediate System-to-Intermediate System Overload Bit Setting in
MPLS-TE
The Ignore Intermediate System-to-Intermediate System (IS-IS) overload bit avoidance feature allows network
administrators to prevent RSVP-TE label switched paths (LSPs) from being disabled, when a router in that
path has its Intermediate System-to-Intermediate System (IS-IS) overload bit set.
The IS-IS overload bit avoidance feature is activated using this command:
mpls traffic-eng path-selection ignore overload
The IS-IS overload bit avoidance feature is deactivated using the no form of this command:
no mpls traffic-eng path-selection ignore overload
When the IS-IS overload bit avoidance feature is activated, all nodes, including head nodes, mid nodes, and
tail nodes, with the overload bit set, are ignored. This means that they are still available for use with RSVP-TE
label switched paths (LSPs). This feature enables you to include an overloaded node in CSPF.
Enhancement Options of IS-IS OLA
You can restrict configuring IS-IS overload bit avoidance with the following enhancement options:
• path-selection ignore overload head
OL-28381-02
Cisco ASR 9000 Series Aggregation Services Router MPLS Configuration Guide, Release 4.3.x
MPLS-TE and Fast Reroute over Link Bundles
125