Configuring Dynamic Subscriber Interfaces - Juniper JUNOSE SOFTWARE 11.2.X - BROADBAND ACCESS CONFIGURATION GUIDE 7-20-2010 Configuration Manual

ip share-nexthop
ip source-prefix

Configuring Dynamic Subscriber Interfaces

Copyright © 2010, Juniper Networks, Inc.
Use the no version to remove the association between the layer 2 interface and the
shared IP interface. You can delete shared and primary IP interfaces independently.
See ip share-interface
Use to specify that the shared IP interface dynamically tracks a next hop. If the next
hop changes, the shared IP interface moves to the new layer 2 interface associated
with the IP interface toward the new next hop.
If you issue this command on a shared IP interface, you cannot issue the ip
share-interface command for the interface.
If you issue this command on a shared IP interface, the shared interface cannot
dynamically track the next hop for the specified destination if the next-hop IP address
is resolvable over MPLS.
If you specify a virtual router, the command fails if the VR does not already exist. If you
do not specify a VR, the current VR is assumed.
After creating the shared IP interface, you can configure it as you do any other IP
interface.
The shared interface is operationally up when the layer 2 interface associated with the
specified next hop is operationally up and IP is properly configured.
Example
host1(config-if)#ip share-nexthop 192.168.10.16
Use the no version to halt tracking of the next hop.
See ip share-nexthop
Use to specify a source address for a subscriber interface.
On the ERX1440 router or the E320 router, you can configure up to 1024 subnets for
static subscriber interfaces per primary IP interface when each subnet has a variable
network mask that is less than /32. The number of subnets identifying a single route
(/32) is still limited by the global maximum of 16,000 hosts per line module.
Example
host1(config-if)#ip source-prefix 192.168.0.0 255.0.0.0
Use the no version to remove the association between the interface and the specified
IP source address and mask.
See ip source-prefix
You can configure dynamic subscriber interfaces in the following configurations:
Chapter 25: Configuring Subscriber Interfaces
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