iRule to monitor BGP attributes and force failover

Here is the scenario ...

 

 

We need a yes/no answer on whether it is possible to create an iRule to accomplish the following tasks:

 

 

1) First the design description – Two F5 Viprions are built as a redundant pair with network failover. They have LTM and Adv. Routing Module. Both Viprions are connected directly to the same ISP with separate routed links. The two Viprions are running eBGP to the ISP and “Viprion1” (active unit) has the preferred default route ….Viprion2 (standby). The two Viprions are running iBGP between each other across the dedicated failover LAN link.

 

 

2) The iRule request – is it possible to build an iRule to accomplish the following:

 

a. Watch a BGP attribute such as “next hop” or “community”

 

 

b. When the “next hop” or “community” disappears (failure occurs at ISP) then make Viprion2 the active/primary unit (cause HA switchover to accur)

 

 

c. Continue to watch the “next hop” or “community” attributes in such a way that – when the BGP attribute become visible again at Viprion1 (when ISP fixes failure) then iRule should force Viprion1 to take over again as the active/primary unit (and Viprion2 goes back to standby).

 

 

d. Please note- We need some intelligence built into the iRule such that it prevents flapping of the active/standby units due to problems at the ISP. In other words, the iRule should watch the failed link to make sure that it has proven itself as solid before making the switchover back to primary role.