HA with an Additional Poller

negative. The HA option only work to pair the main Orion server with a passive Orion server. Or pairing a polling engine with a passive polling engine. In either scenario only the active side of the HA pair/pool can poll.

Is running an Active/Active possible with the HA pool or is this something that would have to be achieved through a NLB?

Today, HA is only Active/Passive. What are the recovery time objectives (RTO) with the DR plan you're working with? Theoretically, HA should take only a few minutes to fail over, but it only covers the application server, not the back end DB. For the DB side, you'd have to leverage one of Microsoft's HA strategies.

There is also just a cold backup of just the database, but depending on how many Orion modules we're working with it could take several hours to re-install Orion and restore the DB to get it working again.

The currently  Orion environment. have requisits for user HA ????

Remeber need same subnet.

If not I Think you user FoE is better.

HA has no requirement that resources match between members of the pool. You cannot however failover from an Main Poller to an Additional Poller. You may want to consider having a less powerful system at the DR location. In the event of a failure the worst that could occur is that polling is somewhat delayed and the website is slow. In the event of a disaster though, it's better to have something rather than nothing.

A good article which should help

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