Apologies in delayed response. I checked with internal team on this to get more details.
Whether the cluster continues running depends on how many nodes are online in the other regions—the remaining nodes need a majority of votes in the cluster quorum, which could be tricky if you have two nodes + the cloud witness go down together.
Here is an example of four nodes plus a witness:
• In this example, if you had two nodes + the witness go offline, the cluster would go down because the remaining two nodes have 2/5 of the votes, which doesn’t comprise a majority.
• I’m thinking in this kind of scenario, you might want to put the cloud witness in a different region than the primary region so it can act in its intended role as an external tiebreaker.
Hope this info helps.
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