Usage Guidelines and Limitations
The TI-LFA guidelines and limitations are listed below:
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TI-LFA segment zero and segment one are supported. Segment two is unsupported.
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Link protection in topologies is supported.
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TI-LFA is supported only on the Distributed Network Architecture (DNX) platform.
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Bundles with multiple members may experience convergence times exceeding fifty milliseconds during Fast Reroute (FRR) switchover.
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IGP directly programs a TI-LFA backup path requiring 3 or fewer labels, including the label of the protected destination prefix.
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The platform does not support programming of TI-LFA backup paths requiring more than 3 labels.
TI-LFA Functionality | IS-IS1 | OSPFv2 |
---|---|---|
Protected Traffic Types | ||
Protection for SR labeled traffic | Supported | Supported |
Protection of IPv4 unlabeled traffic | Supported (IS-ISv4) | Supported |
Protection of IPv6 unlabeled traffic |
Supported (IS-ISv6) |
N/A |
Protection Types | ||
Link Protection | Supported | Supported |
Node Protection | Supported | Supported |
Local SRLG Protection | Supported | Supported |
Weighted Remote SRLG Protection |
Supported |
Supported |
Line Card Disjoint Protection |
Supported |
Unsupported |
Interface Types | ||
Ethernet Interfaces | Supported | Supported |
TI-LFA with L3VPN |
Supported |
Supported |
Ethernet Bundle Interfaces |
Supported |
Supported |
TI-LFA over GRE Tunnel as Protecting Interface |
Supported |
Supported |
Additional Functionality | ||
Maximum number of labels that can be pushed on the backup path (including the label of the protected prefix) | 3 | 3 |
BFD-triggered | Supported | Supported |
BFDv6-triggered | Supported |
N/A |
Prefer backup path with lowest total metric |
Supported |
Supported |
Prefer backup path from ECMP set | Supported | Supported |
Prefer backup path from non-ECMP set | Supported | Supported |
Load share prefixes across multiple backups paths |
Supported |
Supported |
Limit backup computation up to the prefix priority | Supported | Supported |