Specifications

mpls ldp advertise-labels
MP-199
Cisco IOS Multiprotocol Label Switching Command Reference
January 2010
Usage Guidelines This command is used to control which labels are advertised to which LDP neighbors. To prevent the
distribution of any locally assigned labels, use the no mpls ldp advertise-labels
command with no
optional parameters. To reenable the distribution of all locally assigned labels to all LDP neighbors, use
the mpls ldp advertise-labels c
ommand with no optional parameters.
You can execute multiple mpls ldp advertise-labels co
mmands. In the aggregate, such commands
determine how the LSR advertises local labels. The following rules describe the effects of multiple
commands:
1. Every mpls ldp advertise-labels command has a (prefix acl, peer acl) pair associated with it. The
access list pair associated with the mpls ldp advertise-labels com
mand (in the absence of both the
for and to keywords) is (none, none); the access list pair associated with the
mpls ldp advertise-labels for pr
efix acl command (in the absence of the to keyword) is
(prefix-acl, none).
2. A given prefix can have, at most, one (prefix acl, peer acl) pair that “applies” to it, as in the following
explaination:
a. A given (prefix acl, peer acl) pair “applies” to a prefix only if the prefix acl “matches” the
prefix. A match occurs if the prefix acl permits the prefix.
b. If more than one (prefix acl, peer acl) pair from multiple mpls ldp advertise-labels commands
matches a prefix, the (prefix acl, peer acl) pair in the first such command (as determined by the
show running command) “applies” to the prefix.
3. When an LSR is ready to advertise a label for a prefix, the LSR:
a. Determines whether a (prefix acl, peer acl) pair applies to the prefix.
b. If none applies, and if the no mpls ldp advertise-labels command has been configured, the
label for the prefix is not advertised to any peer; otherwise, the label is advertised to all peers.
c. If a (prefix acl, peer acl) pair applies to the prefix, and if the prefix acl “denies” the prefix, the
label is not advertised to any peer.
d. If the prefix acl “permits” the prefix and the peer acl is none (that is, the command that “applies”
to the prefix is an mpls ldp advertise-labels for prefix acl command without the to keyword),
then the label is advertised to all peers.
e. If the prefix acl “permits” the prefix and there is a peer acl, then the label is advertised to all
peers permitted by the peer acl.
Note The mpls ldp advertise-labels command has no effect on an LC-ATM interface. Such an interface
behaves as though this command had not been executed.
12.0(23)S This command was integrated into Cisco IOS Release 12.0(23)S.
12.2(14)S This command was integrated into Cisco IOS Release 12.2(14)S.
12.2(13)T This command was integrated into Cisco IOS Release 12.2(13)T.
12.2(28)SB This command was integrated into Cisco IOS Release 12.2(28)SB and
i
mplemented on the Cisco 10000-PRE2 router.
12.2(33)SRA This command was integrated into Cisco IOS Release 12.2(33)SRA.
12.2SX This command is supported in the Cisco IOS Release 12.2SX train. Support
i
n a specific 12.2SX release of this train depends on your feature set,
platform, and platform hardware.
Release Modification