Hi Dormelchen2,
So the first thing I would confirm is if DataCore supports the concept of a witness, i.e. how does the storage determine which side is not available. Without this you could get into a split brain scenario and have both sides hosting the same VMs.
Once you have determined a way for the storage to keep consistent between both sites plus work out which site is down, then you can start to look at the possibility of implementing Host Isolation. Here is a couple of good blog articles that explain the concept:
- HA split brain, which VM prevails? - VMware vSphere Blog
- vSphere HA isolation response... which to use when? - VMware vSphere Blog
- https://kb.vmware.com/s/article/1030320
So by using something that both sides of your ESXi cluster can see, will allow them to work out which side is surviving. From there the otherside will power down the VMs and then start on hosts which are not isolated. Problems I can see however is that replication will also be severed between the two storage arrays so what is the arrays response to this situation as well?
- Does it break replication therefore allowing host access to continue?
- Does it stop the source machines from talking to the array until replication is resumed?
This also needs to be determined so you know where your data is and what point of time the VMs are at.
Kind regards.