/**
* Add a namenode to cluster and start it. Configuration of datanodes in the cluster is refreshed
* to register with the new namenode.
*
* @return newly started namenode
*/
public NameNodeInfo addNameNode(Configuration conf) throws IOException {
if (!federation) {
throw new IOException("cannot add namenode to non-federated cluster");
}
int nnIndex = nameNodes.length;
int numNameNodes = nameNodes.length + 1;
NameNodeInfo[] newlist = new NameNodeInfo[numNameNodes];
System.arraycopy(nameNodes, 0, newlist, 0, nameNodes.length);
nameNodes = newlist;
nameNodes[nnIndex] = new NameNodeInfo(nnIndex);
NameNodeInfo nni = nameNodes[nnIndex];
nni.createAvatarDirs();
String nameserviceId = NAMESERVICE_ID_PREFIX + nnIndex;
String nameserviceIds = conf.get(FSConstants.DFS_FEDERATION_NAMESERVICES);
nameserviceIds += "," + nameserviceId;
nni.initGeneralConf(conf, nameserviceId);
conf.set(FSConstants.DFS_FEDERATION_NAMESERVICES, nameserviceIds);
nni.updateAvatarConf(conf);
startAvatarNode(nni);
// Refresh datanodes with the newly started namenode
for (DataNodeProperties dn : dataNodes) {
DataNode datanode = dn.datanode;
datanode.refreshNamenodes(conf);
}
// Wait for new namenode to get registrations from all the datanodes
waitDataNodesActive(nnIndex);
return nni;
}
private void startAvatarNodes() throws IOException {
for (NameNodeInfo nni : this.nameNodes) {
nni.updateAvatarConf(this.conf);
startAvatarNode(nni);
}
}
