This document describes Satoshi Tagomori's experience upgrading his Hadoop cluster from HDP 2.1 to HDP 2.2. He encountered issues when running the HDFS namenode upgrade command, with it running indefinitely. Attempts to rollback to HDP 2.1 were also unsuccessful. Restoring from a backup of the namenode metadata and restarting the cluster on HDP 2.1 recovered it, but block replication numbers were