Alcatel-Lucent 7450 Manual page 653

Note that because LDP can detect the loss of a neighbor/next-hop independently, it is possible that it
switches to the LFA next-hop while IGP is still using the primary next-hop. Also, when the interface
for the previous primary next-hop is restored, IGP may re-converge before LDP completed the FEC
exchange with it neighbor over that interface. This may cause LDP to de-program the LFA next-hop
from the FEC and blackhole traffic. In order to avoid this situation, it is recommended to enable IGP-
LDP synchronization on the LDP interface.
When the SPF computation determines there is more than one primary next-hop for a prefix, it will
not program any LFA next-hop in RTM. Thus, the LDP FEC will resolve to the multiple primary
next-hops that provide the required protection.
The no form of this command disables LDP FRR.
Default no fast-reroute
fec-originate
Syntax fec-originate ip-prefix/mask [advertised-label in-label] [swap-label out-label] interface
interface-name
fec-originate ip-prefix/mask [advertised-label in-label] next-hop ip-address [swap-label
out-label]
fec-originate ip-prefix/mask [advertised-label in-label] next-hop ip-address [swap-label
out-label] interface interface-name
fec-originate ip-prefix/mask [advertised-label in-label] pop
no fec-originate ip-prefix/mask interface interface-name
no fec-originate ip-prefix/mask next-hop ip-address
no fec-originate ip-prefix/mask next-hop ip-address interface interface-name
no fec-originate ip-prefix/mask pop
Context config>router>ldp
Description This command defines a way to originate a FEC (with a swap action) for which the LSR is not egress,
or to originate a FEC (with a pop action) for which the LSR is egress.
Parameters ip-prefix/mask — Specify information for the specified IP prefix and mask length.
next-hop — Specify the IP address of the next hop of the prefix.
advertised-label — Specify the label advertised to the upstream peer. If not configured, then the
7450 ESS MPLS Guide
Values <ip-address/mask>
label advertised should be from the label pool. If the configured static label is not available then
the IP prefix is not advertised.
ipv4-prefix - a.b.c.d
ipv4-prefix-le - [0..32]
ipv6-prefix x:x:x:x:x:x:x:x (eight 16-bit pieces)
x:x:x:x:x:x:d.d.d.d
x - [0..FFFF]H
d - [0..255]D
ipv6-prefix-le - [0..128]
Generic Commands
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