Package org.apache.hadoop.hdfs.server.blockmanagement

Class CombinedHostFileManager

java.lang.Object

org.apache.hadoop.hdfs.server.blockmanagement.HostConfigManager

org.apache.hadoop.hdfs.server.blockmanagement.CombinedHostFileManager

All Implemented Interfaces:

org.apache.hadoop.conf.Configurable

public class CombinedHostFileManager
extends HostConfigManager

This class manages datanode configuration using a json file. Please refer to CombinedHostsFileReader for the json format.

Entries may or may not specify a port. If they don't, we consider them to apply to every DataNode on that host. The code canonicalizes the entries into IP addresses.

The code ignores all entries that the DNS fails to resolve their IP addresses. This is okay because by default the NN rejects the registrations of DNs when it fails to do a forward and reverse lookup. Note that DNS resolutions are only done during the loading time to minimize the latency.

Constructor Summary

Constructors

Constructor	Description
CombinedHostFileManager()

Method Summary

Modifier and Type	Method	Description
org.apache.hadoop.conf.Configuration	getConf()
java.lang.Iterable<java.net.InetSocketAddress>	getExcludes()	Return all datanodes that should be in decommissioned state.
java.lang.Iterable<java.net.InetSocketAddress>	getIncludes()	Return all the datanodes that are allowed to connect to the namenode.
long	getMaintenanceExpirationTimeInMS(org.apache.hadoop.hdfs.protocol.DatanodeID dn)	Get the maintenance expiration time in milli seconds.
java.lang.String	getUpgradeDomain(org.apache.hadoop.hdfs.protocol.DatanodeID dn)	Get the upgrade domain of a datanode.
boolean	isExcluded(org.apache.hadoop.hdfs.protocol.DatanodeID dn)	Check if a datanode needs to be decommissioned.
boolean	isIncluded(org.apache.hadoop.hdfs.protocol.DatanodeID dn)	Check if a datanode is allowed to connect the namenode.
void	refresh()	Reload the configuration.
void	setConf(org.apache.hadoop.conf.Configuration conf)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

CombinedHostFileManager

public CombinedHostFileManager()

Method Detail

getIncludes

public java.lang.Iterable<java.net.InetSocketAddress> getIncludes()

Description copied from class: HostConfigManager

Return all the datanodes that are allowed to connect to the namenode.

Specified by:

getIncludes in class HostConfigManager

Returns:

Iterable of all datanodes

getExcludes

public java.lang.Iterable<java.net.InetSocketAddress> getExcludes()

Description copied from class: HostConfigManager

Return all datanodes that should be in decommissioned state.

Specified by:

getExcludes in class HostConfigManager

Returns:

Iterable of those datanodes

setConf

public void setConf(org.apache.hadoop.conf.Configuration conf)

getConf

public org.apache.hadoop.conf.Configuration getConf()

refresh

public void refresh()
             throws java.io.IOException

Description copied from class: HostConfigManager

Reload the configuration.

Specified by:

refresh in class HostConfigManager

Throws:

java.io.IOException

isIncluded

public boolean isIncluded(org.apache.hadoop.hdfs.protocol.DatanodeID dn)

Description copied from class: HostConfigManager

Check if a datanode is allowed to connect the namenode.

Specified by:

isIncluded in class HostConfigManager

Parameters:

dn - the DatanodeID of the datanode

Returns:

boolean if dn is allowed to connect the namenode.

isExcluded

public boolean isExcluded(org.apache.hadoop.hdfs.protocol.DatanodeID dn)

Description copied from class: HostConfigManager

Check if a datanode needs to be decommissioned.

Specified by:

isExcluded in class HostConfigManager

Parameters:

dn - the DatanodeID of the datanode

Returns:

boolean if dn needs to be decommissioned.

getUpgradeDomain

public java.lang.String getUpgradeDomain(org.apache.hadoop.hdfs.protocol.DatanodeID dn)

Description copied from class: HostConfigManager

Get the upgrade domain of a datanode.

Specified by:

getUpgradeDomain in class HostConfigManager

Parameters:

dn - the DatanodeID of the datanode

Returns:

the upgrade domain of dn.

getMaintenanceExpirationTimeInMS

public long getMaintenanceExpirationTimeInMS(org.apache.hadoop.hdfs.protocol.DatanodeID dn)

Description copied from class: HostConfigManager

Get the maintenance expiration time in milli seconds.

Specified by:

getMaintenanceExpirationTimeInMS in class HostConfigManager

Parameters:

dn - the DatanodeID of the datanode

Returns:

the maintenance expiration time of dn.