In addition to link LDP, a policy can be assigned to mLDP as an import policy. For example, if the following policy was assigned as an import policy to mLDP, any FEC arriving with an IP address of 100.0.1.21 is dropped.
*A:SwSim2>config>router>policy-options# info
----------------------------------------------
prefix-list "100.0.1.21/32"
prefix 100.0.1.21/32 exact
exit
policy-statement "policy1"
entry 10
from
prefix-list "100.0.1.21/32"
exit
action drop
exit
exit
entry 20
exit
default-action accept
exit
exit
The policy can be assigned to mLDP using the configure router ldp import-mcast-policy policy1 command. Based on this configuration, the prefix list matches the mLDP outer FEC and the action is executed.
The mLDP import policy is useful for enforcing root only functionality on a network. For a PE to be a root only, enable the mLDP import policy to drop any arriving FEC on the P router.