question Re: Getting error while trying to connect HBase using spark. in Archives of Support Questions (Read Only)

Getting error while trying to connect HBase using spark.

contactvivekjai — Mon, 02 Jul 2018 09:36:37 GMT

Hi Community,

I'm new to spark and have been struggling to execute a spark job which connects to a HBase table.

In YARN GUI I can see the spark job is getting to state Running but then it fails with below error :

18/07/01 21:08:20 INFO ZooKeeper: Initiating client connection, connectString=localhost:2181 sessionTimeout=90000 watcher=hconnection-0x6a8bcb640x0, quorum=localhost:2181, baseZNode=/hbase 18/07/01 21:08:20 INFO ClientCnxn: Opening socket connection to server localhost.localdomain/127.0.0.1:2181. Will not attempt to authenticate using SASL (unknown error) 18/07/01 21:08:20 WARN ClientCnxn: Session 0x0 for server null, unexpected error, closing socket connection and attempting reconnect java.net.ConnectException: Connection refused at sun.nio.ch.SocketChannelImpl.checkConnect(Native Method) at sun.nio.ch.SocketChannelImpl.finishConnect(SocketChannelImpl.java:717) at org.apache.zookeeper.ClientCnxnSocketNIO.doTransport(ClientCnxnSocketNIO.java:361) at org.apache.zookeeper.ClientCnxn$SendThread.run(ClientCnxn.java:1125) 18/07/01 21:08:20 WARN RecoverableZooKeeper: Possibly transient ZooKeeper, quorum=localhost:2181, exception=org.apache.zookeeper.KeeperException$ConnectionLossException: KeeperErrorCode = ConnectionLoss for /hbase/hbaseid

ZooKeeper is up and running. Below is my code

//Create table catalog
object foo {
  def catalog = s"""{
         |"table":{"namespace":"foo", "name":"bar"},
         |"rowkey":"key",
         |"columns":{
           |"col0":{"col":"key", "type":"string"},
           |"col1":{"cf":"data", "col":"id", "type":"bigint"}
         |}
       |} "" ". stripMargin

  def main(args: Array[String]) {
     val spark = SparkSession.builder()
      .appName("foo")
      .getOrCreate()
    choose sc = kick.sparkContext
    val sqlContext = spark.sqlContext
    
    import sqlContext.implicits._
     def withCatalog(cat: String): DataFrame = {
      sqlContext
        .read
        .options(Map(HBaseTableCatalog.tableCatalog -> cat))
        .format("org.apache.spark.sql.execution.datasources.hbase")
        .load()
    }
// Read from HBase table
   val df = withCatalog(catalog)
    df.show
    df.filter($"col0" === "1528801346000_200550232_2955")
      .select($"col0", $"col1").show
   spark.stop()
  }

I'll really appreciate any help on this. I couldnt find any convincing answer in stackoverflow as well.

Re: Getting error while trying to connect HBase using spark.

karthiknedunche — Mon, 02 Jul 2018 11:52:48 GMT

@vivek jain

Can you upload your hbase configuration file.

Re: Getting error while trying to connect HBase using spark.

contactvivekjai — Mon, 02 Jul 2018 14:56:27 GMT

@karthik nedunchezhiyan I have attached hbase-site.xml, I hope it helps.

Re: Getting error while trying to connect HBase using spark.

sandyy006 — Mon, 02 Jul 2018 23:18:17 GMT

@vivek jain

It seems that the app is not picking up the hbase-site.xml and is connecting to localhost (connectString=localhost:2181).

copy hbase-site.xml to /etc/spark/conf/ in the node where you are launching the job and also pass the hbase-site.xml using --files in spark-submit command (--files /etc/spark/conf/hbase-site.xml).

Re: Getting error while trying to connect HBase using spark.

contactvivekjai — Tue, 03 Jul 2018 19:37:02 GMT

Hi @Sandeep Nemuri thanks for answering. I did as mentioned above and now my code runs fine with deploy-mode as client, but now I ran into another issue where the data displayed is blank. However I can see the data on hbase shell prompt. I have already checked the rowkey,table name and namespace name. What do you think is missing ?

val df = withCatalog(catalog)
    df.show
   df.select($"col0").show(10)
   spark.stop()

Re: Getting error while trying to connect HBase using spark.

sandyy006 — Tue, 03 Jul 2018 19:45:52 GMT

@vivek jain Glad that it worked, Would you mind marking this thread as closed by clicking on "Accept" and asking a new question with the code used and the console output.

Re: Getting error while trying to connect HBase using spark.

contactvivekjai — Tue, 03 Jul 2018 21:58:35 GMT

@Sandeep Nemuri thanks for the help, surely will do so.