HDFS-7257. Add the time of last HA state transition to NN's /jmx page. Contributed by Charles Lamb.
HADOOP-11170. ZKDelegationTokenSecretManager fails to renewToken created by a peer. (Arun Suresh and Gregory Chanan via kasha)
HDFS-7223. Tracing span description of IPC client is too long (iwasakims via cmccabe)
HDFS-7243. HDFS concat operation should not be allowed in Encryption Zone. (clamb via yliu)