Configure ArcGIS Object datastore in High Availability

[DrAnandAkmanchi]

Hi,

We are going to deploy an ArcGIS Enterprise v11.4 in high availability with a total of eight machines:-

1. Two portal machines

2. Two hosting server machines 

3. Two datastores (relational + object) machines

4. Two webadaptor machines

I have doubts about deploying an object datastore in a high availability configuration, which consists of two machines. Which mode do I need to select, SingleInstance or cluster? As per the documentation, I am pretty clear that the mode can't be the SingleInstance for cluster mode; the documentation says that -

For SingleInstance mode only one machine is required and for cluster mode at least three machines are required but if we have only two machines for object datastore then which mode I need to select. 

                                                             Or 

It is not possible to configure an object datastore with two machines.

Any response will be highly appreciated!

Thanks

Ayush

[DavidCrosby]

It's not possible to configure the Object Store on just two machines.  You will need cluster mode and three machines for a proper HA configuration.  While you could do a single instance mode and install on one of the Data Store servers I would not suggest it, as it would not be HA and the mode cannot be changed after the initial configuration.