I'm in the process of validating if we lost data due to doing a (partial for now) rolling reprovision / node failures in the past.
It seems that closed indices, not being part of the recovery process, can lose their replica during a full node failure. Due to the index being closed, even when the cluster is 'green' again the replica will not be recreated. Due to this a future full node failure (or the next node reprovision) could impact the primary, causing data loss.
Is this a correct assumption? I can find zero documentation about closed index behaviour during node failures.