Using the 4.14.3 client, it still seems the IndexFailurePolicy is still kicking in, which disables the index on write failure. This means that while the index is in 'disabled' state, writes to the data table can happen without any writes to the index table. While in theory this might be ok since the rebuilder should eventually kick in and rebuild from the disable_timestamp, this breaks the new indexing design invariant that there should be no data table rows without a corresponding index row (potentially unverified), so this could potentially cause some unexpected behavior.
Steps to repro:
1) Create data table
2) Create index table
3) "close_region" on index region from hbase shell
4) Upsert to data table
Eventually after some number of retries, the index will get disabled, which means any other client can write to the data table without writing to the index table.