There are three cases with its own specifics:
subscriber interface routes (IPv4/IPv6)
managed routes
subscriber management Routes (/32 IPv4 hosts routes and IPv6 PD wan-host routes)
Depending on the route type, the action is to either modify the route metric based on the SRRP state that the route is tracking, or to advertise/withdraw the route based on the SRRP state that the route is tracking. The action is defined in the routing policy and it is based on the new attributes with which the routes are associated.
To achieve a better granularity of the routes that are advertised, an origin attribute is added to the subscriber management routes (/32 IPv4 routes and IPv6 PD wan-host) with three possible values:
aaa
IPv4
subscriber-management /32 host routes that are originated through RADIUS framed-ip-address VSA other than 255.255.255.254. The 255.255.255.254 returned by the RADIUS indicates that the BNG (NAS) should assign an IP address from its own pool.
IPv6
subscriber-management routes that are originated through framed-ipv6-prefix (SLAAC), delegated-ipv6-prefix (IA_PD) or alc-ipv6-address (IA_NA) RADIUS attributes. This is valid for IPoE and PPPoE type host.
dynamic
IPv4
subscriber-management /32 host routes that are originated through the DHCP server (local or remote) and also RADIUS framed-ip-address=255.255.255.254 (RFC 2865).
IPv6
subscriber-management routes that are assigned through the local DHCPv6 server pools whose name is obtained through Alc-Delegated-IPv6-Pool (PD pool) and Framed-IPv6-Pool (NA pool) RADIUS attributes. This is valid for IPoE and PPPoE type hosts.
In addition, for IPoEv6 only, the pool name can be also obtained through the ipv6-delegated-prefix-pool (PD pool) and ipv6-wan-address-pool (NA pool) from LUDB.
static
IPv4
subscriber-management /32 host routes that are originated through LUDB. This also covers RADIUS fallback category (RADIUS falls back to system-defaults or to LUDB).
IPv6
subscriber-management routes obtained from LUDB through the ipv6-address (IA_NA) or ipv6-prefix (IA_PD). This is supported only for IPoE.
Overall, the following new route attribute is added:
state: srrp-master, srrp-non-master
The existing origin attribute is expanded to contain the following values:
origin: aaa, dynamic, static
These two attribute types are applied:
The state attribute is applied to all three route types: subscriber interface routes, managed routes and subscriber management routes. Each route listens to the SRRP state.
If an attribute is defined in the routing policy as a match condition (from statement) but the route itself does not have this attribute, the route is evaluated into a non-match condition.
The origin attribute is always applied only to subscriber management routes. No additional statement is needed to explicitly apply this attribute as it may be the case for the state attribute.
Every time there is a change in the attribute associated with the route, the route is re-evaluated in the RTM by the routing policy and corresponding action is taken.