In a IPMP probe based active active configuration ,if for any reason the production/data interface g

I have a two node sun cluster 3.2.

1.2.3.146 is the production IP on e1000g0 which client uses for production access.

1.2.3.147 is a test address and interace is e1000g0:1

1.2.3.148 is another test address.

It is a active active probe based configuration.

If e1000g0 fails , will the traffic in 1.2.3.146 travel through 1.2.3.148.

What is the role of this .148 in active active probe IPMP configuration ?