Provide high availability for sFlow/Netflow

For reference this originated in support case 17038

Currently the LM platform does not support HA for sflow/Netflow.

I can\'t speak to all network devices certainly but my switches support sending sFlow data to up to 4 collectors. So one way to provide high availability is to configure two agents to receive the sFlow data and just ignore the data on the \'\'backup\'\' collector unless the primary fails for some reason.

There are other was too I am sure that may be the simplest though.