This section describes configuration changes for other parameters.
The properties listed below cannot be used with this product. This information is provided for reference only.
hadoop-env.sh
Environment variable | Default value/Value to be set |
|---|---|
HADOOP_DATANODE_OPTS Launch option specifically for the JVM that operates DataNode | Default value -Dcom.sun.management.jmxremote $HADOOP_DATANODE_OPTS Value to be set -Xmx$$m -Dhadoop.security.logger=ERROR,DRFAS $$ = The lesser of the following values:
|
HADOOP_NAMENODE_OPTS Launch option specifically for the JVM that operates NameNode | Default value -Dcom.sun.management.jmxremote $HADOOP_NAMENODE_OPTS Value to be set -Xmx$$m -Dhadoop.security.logger=INFO,DRFAS $$ = physicalMemorySizeInMb / 4 |
HADOOP_SECONDARYNAMENODE_OPTS Launch option specifically for the JVM that operates SecondaryNameNode | Default value -Dcom.sun.management.jmxremote $HADOOP_SECONDARYNAMENODE_OPTS Value to be set -Xmx$$m -Dhadoop.security.logger=INFO,DRFAS $$ = physicalMemorySizeInMb / 4 |
core-site.xml
Property | Default value/Value to be set |
|---|---|
fs.checkpoint.dir Directory storing the HDFS management information for SecondaryNameNode | Default value ${hadoop.tmp.dir}/dfs/namesecondary Value to be set /var/lib/hadoop/hdfs/namesecondary |
fs.checkpoint.period Interval (seconds) at which the NameNode change history is reflected (redundancy is performed) to SecondaryNameNode | Default value 3600 (60 minutes) Value to be set 1800 (30 minutes) |
hdfs-site.xml
This setup file cannot be used with this product.
Property | Default value/Value to be set |
|---|---|
dfs.block.size Size of the local file (bytes) when storing the HDFS file blocks in the local file | Default value 67108864 (64 MB) Value to be set 134217728 (128 MB) |
dfs.datanode.du.reserved Size of the disk (bytes) to which dfs.data.dir is deployed, where dfs.data.dir is reserved for use with data other than HDFS data | Default value 0 Value to be set Set at 40% (bytes) of the available space on the disk where dfs.data.dir is deployed |
dfs.datanode.handler.count Number of threads performing processes within DataNode | Default value 3 Value to be set The greater of the following values:
|
dfs.datanode.ipc.address Address for sending and receiving data between DataNodes | Default value 0.0.0.0:50020 Value to be set 0.0.0.0:50020 (reset) |
dfs.datanode.max.xcievers Maximum number of connections to DataNode | Default value 256 Value to be set 4096 |
dfs.permissions.supergroup HDFS supergroup name | Default value supergroup Value to be set hadoop |
dfs.support.append Whether the HDFS append feature is used | Default value false Value to be set true |
