Virtual Private Routed Network Services
7750 SR OS Services Guide Page 861
For proper operation, each subscriber subnet associated with the SRRP instance must have a gw-
address defined. The SRRP instance cannot be activated (no shutdown) unless each subscriber 
subnet associated with the group IP interface has an SRRP gateway IP address. Once the SRRP 
instance is activated, new subscriber subnets cannot be added without a corresponding SRRP 
gateway IP address. Table 2.2 describers how the SRRP instance state is used to manage access to 
subscriber hosts associated with the group IP interface.
SRRP instances are created in the disabled state (shutdown). To activate SRRP the no shutdown 
command in the SRRP context must be executed.
Before activating an SRRP instance on a group IP interface, the following actions are required:
• Add SRRP gateway IP addresses to all subscriber subnets associated with the group IP 
interface, including subnets on subscriber IP interfaces associated as retail routing 
contexts (at least one subnet must be on the subscriber IP interface containing the group IP 
interface and its SRRP instance)
• Create a redundant IP interface and associate it with the SRRP instances group IP 
interface for shunting traffic to the remote router when master
• Specify the group IP interface SAP used for SRRP advertisement and Information 
messaging
Before activating an SRRP instance on a group IP interface, the following actions should be 
considered:
• Associate the SRRP instance to a Multi-Chassis Synchronization (MCS) peering 
terminating on the neighboring router (the MCS peering should exist as the peering is 
required for redundant subscriber host management)
• Define a description string for the SRRP instance
• Specify the SRRP gateway MAC address used by the SRRP instance (must be the same 
on both the local and remote SRRP instance participating in the same SRRP context)
• Change the base priority for the SRRP instance
• Specify one or more VRRP policies to dynamically manage the SRRP instance base 
priority
• Specify a new keep alive interval for the SRRP instance