We have a Splunk infrastructure with ESS using SmartStore over S3 on AWS. We moved from Splunk 7.3.0 to 7.3.4 and none errors appeared during the update procedure.
Once we disabled the maintenance mode, the Replication Factor and the Search Factor never met due to 2 buckets inside two different indexes. We are trying to fixup those buckets, but it never completed and looks stuck in target_wait_time status.
After having looked inside S3 itself, we noticed that the folders which are being referenced inside Splunk are not present in there.