Java/Scala客户端获取HA高可用HDFS的Active NameNode

1. Java/Scala客户端获取HA高可用HDFS的Active NameNode

通过轮询的方式判断多个Namenode是否可用。如果当前NameNode不可用，则继续判断下一个；如果可用，则获取当前NameNode的Uri

示例代码

import org.apache.hadoop.conf.Configuration
import org.apache.hadoop.fs.FileSystem
import org.apache.hadoop.ipc.StandbyException

import scala.util.control.Breaks.{break, breakable}


object HadoopTest {

  def main(args: Array[String]): Unit = {

    val hadoopConf = new Configuration()
    val hdfsUris = Array(
      "hdfs://192.168.23.101:8020",
      "hdfs://192.168.23.102:8020",
      "hdfs://192.168.23.103:8020"
    )
    var hdfsCli: FileSystem = null
    var hdfsCapacity: Long = -1L
    var activeHdfsUri: String = null

    breakable {
      for (hdfsUri  {}
        }

      }
    }

    println(activeHdfsUri)

  }
}