| name | value | description |
| dfs.namenode.logging.level | info | The logging level for dfs namenode. Other values are "dir"(trac
e namespace mutations), "block"(trace block under/over replications and block
creations/deletions), or "all". |
| dfs.secondary.http.address | 0.0.0.0:50090 |
The secondary namenode http server address and port.
If the port is 0 then the server will start on a free port.
|
| dfs.datanode.address | 0.0.0.0:50010 |
The address where the datanode server will listen to.
If the port is 0 then the server will start on a free port.
|
| dfs.datanode.http.address | 0.0.0.0:50075 |
The datanode http server address and port.
If the port is 0 then the server will start on a free port.
|
| dfs.datanode.ipc.address | 0.0.0.0:50020 |
The datanode ipc server address and port.
If the port is 0 then the server will start on a free port.
|
| dfs.datanode.handler.count | 3 | The number of server threads for the datanode. |
| dfs.http.address | 0.0.0.0:50070 |
The address and the base port where the dfs namenode web ui will listen on.
If the port is 0 then the server will start on a free port.
|
| dfs.https.enable | false | Decide if HTTPS(SSL) is supported on HDFS
|
| dfs.https.need.client.auth | false | Whether SSL client certificate authentication is required
|
| dfs.https.server.keystore.resource | ssl-server.xml | Resource file from which ssl server keystore
information will be extracted
|
| dfs.https.client.keystore.resource | ssl-client.xml | Resource file from which ssl client keystore
information will be extracted
|
| dfs.datanode.https.address | 0.0.0.0:50475 | |
| dfs.https.address | 0.0.0.0:50470 | |
| dfs.datanode.dns.interface | default | The name of the Network Interface from which a data node should
report its IP address.
|
| dfs.datanode.dns.nameserver | default | The host name or IP address of the name server (DNS)
which a DataNode should use to determine the host name used by the
NameNode for communication and display purposes.
|
| dfs.replication.considerLoad | true | Decide if chooseTarget considers the target's load or not
|
| dfs.default.chunk.view.size | 32768 | The number of bytes to view for a file on the browser.
|
| dfs.datanode.du.reserved | 0 | Reserved space in bytes per volume. Always leave this much space free for non dfs use.
|
| dfs.name.dir | ${hadoop.tmp.dir}/dfs/name | Determines where on the local filesystem the DFS name node
should store the name table(fsimage). If this is a comma-delimited list
of directories then the name table is replicated in all of the
directories, for redundancy. |
| dfs.name.edits.dir | ${dfs.name.dir} | Determines where on the local filesystem the DFS name node
should store the transaction (edits) file. If this is a comma-delimited list
of directories then the transaction file is replicated in all of the
directories, for redundancy. Default value is same as dfs.name.dir
|
| dfs.web.ugi | webuser,webgroup | The user account used by the web interface.
Syntax: USERNAME,GROUP1,GROUP2, ...
|
| dfs.permissions | true |
If "true", enable permission checking in HDFS.
If "false", permission checking is turned off,
but all other behavior is unchanged.
Switching from one parameter value to the other does not change the mode,
owner or group of files or directories.
|
| dfs.permissions.supergroup | supergroup | The name of the group of super-users. |
| dfs.block.access.token.enable | false |
If "true", access tokens are used as capabilities for accessing datanodes.
If "false", no access tokens are checked on accessing datanodes.
|
| dfs.block.access.key.update.interval | 600 |
Interval in minutes at which namenode updates its access keys.
|
| dfs.block.access.token.lifetime | 600 | The lifetime of access tokens in minutes. |
| dfs.data.dir | ${hadoop.tmp.dir}/dfs/data | Determines where on the local filesystem an DFS data node
should store its blocks. If this is a comma-delimited
list of directories, then data will be stored in all named
directories, typically on different devices.
Directories that do not exist are ignored.
|
| dfs.datanode.data.dir.perm | 755 | Permissions for the directories on on the local filesystem where
the DFS data node store its blocks. The permissions can either be octal or
symbolic. |
| dfs.replication | 3 | Default block replication.
The actual number of replications can be specified when the file is created.
The default is used if replication is not specified in create time.
|
| dfs.replication.max | 512 | Maximal block replication.
|
| dfs.replication.min | 1 | Minimal block replication.
|
| dfs.block.size | 67108864 | The default block size for new files. |
| dfs.df.interval | 60000 | Disk usage statistics refresh interval in msec. |
| dfs.client.block.write.retries | 3 | The number of retries for writing blocks to the data nodes,
before we signal failure to the application.
|
| dfs.blockreport.intervalMsec | 3600000 | Determines block reporting interval in milliseconds. |
| dfs.blockreport.initialDelay | 0 | Delay for first block report in seconds. |
| dfs.heartbeat.interval | 3 | Determines datanode heartbeat interval in seconds. |
| dfs.namenode.handler.count | 10 | The number of server threads for the namenode. |
| dfs.safemode.threshold.pct | 0.999f |
Specifies the percentage of blocks that should satisfy
the minimal replication requirement defined by dfs.replication.min.
Values less than or equal to 0 mean not to start in safe mode.
Values greater than 1 will make safe mode permanent.
|
| dfs.safemode.extension | 30000 |
Determines extension of safe mode in milliseconds
after the threshold level is reached.
|
| dfs.balance.bandwidthPerSec | 1048576 |
Specifies the maximum amount of bandwidth that each datanode
can utilize for the balancing purpose in term of
the number of bytes per second.
|
| dfs.hosts | | Names a file that contains a list of hosts that are
permitted to connect to the namenode. The full pathname of the file
must be specified. If the value is empty, all hosts are
permitted. |
| dfs.hosts.exclude | | Names a file that contains a list of hosts that are
not permitted to connect to the namenode. The full pathname of the
file must be specified. If the value is empty, no hosts are
excluded. |
| dfs.max.objects | 0 | The maximum number of files, directories and blocks
dfs supports. A value of zero indicates no limit to the number
of objects that dfs supports.
|
| dfs.namenode.decommission.interval | 30 | Namenode periodicity in seconds to check if decommission is
complete. |
| dfs.namenode.decommission.nodes.per.interval | 5 | The number of nodes namenode checks if decommission is complete
in each dfs.namenode.decommission.interval. |
| dfs.replication.interval | 3 | The periodicity in seconds with which the namenode computes
repliaction work for datanodes. |
| dfs.access.time.precision | 3600000 | The access time for HDFS file is precise upto this value.
The default value is 1 hour. Setting a value of 0 disables
access times for HDFS.
|
| dfs.support.append | false | Does HDFS allow appends to files?
This is currently set to false because there are bugs in the
"append code" and is not supported in any prodction cluster.
|
| dfs.namenode.delegation.key.update-interval | 86400000 | The update interval for master key for delegation tokens
in the namenode in milliseconds.
|
| dfs.namenode.delegation.token.max-lifetime | 604800000 | The maximum lifetime in milliseconds for which a delegation
token is valid.
|
| dfs.namenode.delegation.token.renew-interval | 86400000 | The renewal interval for delegation token in milliseconds.
|
| dfs.datanode.failed.volumes.tolerated | 0 | The number of volumes that are allowed to
fail before a datanode stops offering service. By default
any volume failure will cause a datanode to shutdown.
|