These release notes cover new developer and user-facing incompatibilities, important issues, features, and major improvements.
Environment variables for MapReduce tasks can now be specified as separate properties, e.g.: mapreduce.map.env.VARNAME=value mapreduce.reduce.env.VARNAME=value yarn.app.mapreduce.am.env.VARNAME=value yarn.app.mapreduce.am.admin.user.env.VARNAME=value This form of specifying environment variables is useful when the value of an environment variable contains commas.
ZKFC binds host address to “dfs.namenode.servicerpc-bind-host”, if configured. Otherwise, it binds to “dfs.namenode.rpc-bind-host”. If neither of those is configured, ZKFC binds itself to NameNode RPC server address (effectively “dfs.namenode.rpc-address”).
Submitted version of patch for branch-2.10
Azure WASB bug fix that can cause list results to appear empty.
The HADOOP_CONF_DIR environment variable is no longer unconditionally inherited by containers even if it does not appear in the nodemanager whitelist variables specified by the yarn.nodemanager.env-whitelist property. If the whitelist property has been modified from the default to not include HADOOP_CONF_DIR yet containers need it to be inherited from the nodemanager’s environment then the whitelist settings need to be updated to include HADOOP_CONF_DIR.