动态刷新配置：
bin/hdfs dfsadmin –refreshSuperUserGroupsConfiguration
bin/yarn rmadmin –refreshSuperUserGroupsConfiguration
如果集群配置了HA，需要在为主备namenode（node000和node001）同时加载这两个属性（只加载一个不行），命令如下：
bin/hadoop dfsadmin -fs hdfs://node000:8020 –refreshSuperUserGroupsConfiguration
bin/hadoop dfsadmin -fs hdfs://node001:8020 –refreshSuperUserGroupsConfiguration
[hadoop@hadoop1 ~]$ hdfs dfsadmin
Usage: hdfs dfsadmin
Note: Administrative commands can only be run as the HDFS superuser.
[-report [-live] [-dead] [-decommissioning] [-enteringmaintenance] [-inmaintenance]]
[-safemode <enter | leave | get | wait>]
[-saveNamespace [-beforeShutdown]]
[-rollEdits]
[-restoreFailedStorage true|false|check]
[-refreshNodes]
[-setQuota <quota> <dirname>...<dirname>]
[-clrQuota <dirname>...<dirname>]
[-setSpaceQuota <quota> [-storageType <storagetype>] <dirname>...<dirname>]
[-clrSpaceQuota [-storageType <storagetype>] <dirname>...<dirname>]
[-finalizeUpgrade]
[-rollingUpgrade [<query|prepare|finalize>]]
[-upgrade <query | finalize>]
[-refreshServiceAcl]
[-refreshUserToGroupsMappings]
[-refreshSuperUserGroupsConfiguration]
[-refreshCallQueue]
[-refresh <host:ipc_port> <REFRESH_WHITE_LIST | REFRESH_BLACK_LIST | REFRESH_PASSWORD | REFRESH_PROTECTED_DIRECTORIES> [arg1..argn]
[-reconfig <namenode|datanode> <host:ipc_port> <start|status|properties>]
[-printTopology]
[-refreshNamenodes datanode_host:ipc_port]
[-getVolumeReport datanode_host:ipc_port]
[-deleteBlockPool datanode_host:ipc_port blockpoolId [force]]
[-setBalancerBandwidth <bandwidth in bytes per second>]
[-getBalancerBandwidth <datanode_host:ipc_port>]
[-fetchImage <local directory>]
[-allowSnapshot <snapshotDir>]
[-disallowSnapshot <snapshotDir>]
[-shutdownDatanode <datanode_host:ipc_port> [upgrade]]
[-evictWriters <datanode_host:ipc_port>]
[-getDatanodeInfo <datanode_host:ipc_port>]
[-metasave filename]
[-triggerBlockReport [-incremental] <datanode_host:ipc_port>]
[-listOpenFiles [-blockingDecommission] [-path <path>]]
[-help [cmd]]
Generic options supported are:
-conf <configuration file> specify an application configuration file
-D <property=value> define a value for a given property
-fs <file:///|hdfs://namenode:port> specify default filesystem URL to use, overrides 'fs.defaultFS' property from configurations.
-jt <local|resourcemanager:port> specify a ResourceManager
-files <file1,...> specify a comma-separated list of files to be copied to the map reduce cluster
-libjars <jar1,...> specify a comma-separated list of jar files to be included in the classpath
-archives <archive1,...> specify a comma-separated list of archives to be unarchived on the compute machines
The general command line syntax is:
command [genericOptions] [commandOptions]
DFSAdmin.refreshSuperUserGroupsConfiguration方法：
public int refreshSuperUserGroupsConfiguration() throws IOException {
// Get the current configuration
Configuration conf = getConf();
// for security authorization
// server principal for this call
// should be NAMENODE's one.
conf.set(CommonConfigurationKeys.HADOOP_SECURITY_SERVICE_USER_NAME_KEY,
conf.get(DFSConfigKeys.DFS_NAMENODE_KERBEROS_PRINCIPAL_KEY, ""));
DistributedFileSystem dfs = getDFS();
URI dfsUri = dfs.getUri();
boolean isHaEnabled = HAUtilClient.isLogicalUri(conf, dfsUri);
if (isHaEnabled) {
// Run refreshSuperUserGroupsConfiguration for all NNs if HA is enabled
String nsId = dfsUri.getHost();
List<ProxyAndInfo<RefreshUserMappingsProtocol>> proxies =
HAUtil.getProxiesForAllNameNodesInNameservice(conf, nsId,
RefreshUserMappingsProtocol.class);
List<IOException> exceptions = new ArrayList<>();
for (ProxyAndInfo<RefreshUserMappingsProtocol> proxy : proxies) {
try{
proxy.getProxy().refreshSuperUserGroupsConfiguration();
System.out.println("Refresh super user groups configuration " +
"successful for " + proxy.getAddress());
}catch (IOException ioe){
System.out.println("Refresh super user groups configuration " +
"failed for " + proxy.getAddress());
exceptions.add(ioe);
}
}
if(!exceptions.isEmpty()){
throw MultipleIOException.createIOException(exceptions);
}
} else {
// Create the client
RefreshUserMappingsProtocol refreshProtocol =
NameNodeProxies.createProxy(conf, FileSystem.getDefaultUri(conf),
RefreshUserMappingsProtocol.class).getProxy();
// Refresh the user-to-groups mappings
refreshProtocol.refreshSuperUserGroupsConfiguration();
System.out.println("Refresh super user groups configuration successful");
}
return 0;
}
会自动判断是HA，（2.7和3.2后改了）