Accessing the remote CDP cluster HBase data from another CDP cluster using Spark in Kerberized environment.

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This article will describe the steps to access the remote CDP cluster HBase data from another CDP cluster using Spark in Kerberized environment.

Assume we have two clusters say 'Cluster_A' and 'Cluster_B'. 'Cluster_A' is having the HBase data. 'Cluster_B' is having Spark. Now, we are trying to access the HBase data available in 'Cluster_A' using Spark from 'Cluster_B'.

Prerequisites:

Both clusters 'Cluster_A' and 'Cluster_B' with keytabs need to have the same REALM.

Follow these steps: 

1. Login to 'Cluster_A' edge node
2. Obtain the Kerberos ticket using kinit:
   

   kinit -kt <key_tab_file> <principal_name>​

3. Login to the Hbase shell and create the 'person' table:
   

   ranga]# hbase shell
   
   hbase(main):001:0> list
   TABLE
   0 row(s)
   
   hbase(main):013:0> create 'person', 'p'
   Created table person
   Took 8.2307 seconds
   => Hbase::Table - person
   
   hbase(main):014:0> put 'person',1,'p:id','1'
   Took 0.0173 seconds
   hbase(main):015:0> put 'person',1,'p:name','Ranga Reddy'
   Took 0.0045 seconds
   hbase(main):016:0> put 'person',1,'p:email','ranga@gmail.com'
   Took 0.0043 seconds
   hbase(main):017:0> put 'person',1,'p:age','25'
   Took 0.0049 seconds
   hbase(main):018:0> scan 'person'
   ROW                                                              COLUMN+CELL
    1                                                               column=p:age, timestamp=1616425683759, value=25
    1                                                               column=p:email, timestamp=1616425681754, value=ranga@gmail.com
    1                                                               column=p:id, timestamp=1616425681717, value=1
    1                                                               column=p:name, timestamp=1616425681736, value=Ranga Reddy
   
   hbase(main):018:0> exit

4. Copy the hbase-site.xml from 'Cluster_A' to 'Cluster_B':
   

   scp /etc/hbase/conf/hbase-site.xml root@cluster_b_ipaddress:/tmp​

5. Login to 'Cluster_B' edge node
6. Obtain the Kerberos ticket using kinit:
   

   kinit -kt <key_tab_file> <principal_name>

7. Place the above-copied hbase-site.xml (in Step 4) into some temporary directory. Example: /tmp/hbase/conf
   

   mkdir -p /tmp/hbase/conf
   cp /tmp/hbase-site.xml /tmp/hbase/conf

8. Launch the Spark shell by providing HBase Spark connector packages and HBase configuration (/tmp/hbase/conf) directory:
   

   spark-shell \
   --master yarn \
   --conf spark.driver.extraClassPath=/tmp/hbase/conf \
   --conf spark.executor.extraClassPath=/tmp/hbase/conf \
   --jars /opt/cloudera/parcels/CDH/lib/hbase_connectors/lib/hbase-spark-1.0.0*.jar,\
   /opt/cloudera/parcels/CDH/lib/hbase_connectors/lib/hbase-spark-protocol-shaded-*.jar,\
   /opt/cloudera/parcels/CDH/lib/hbase/hbase-client.jar,\
   /opt/cloudera/parcels/CDH/lib/hbase/hbase-common.jar,\
   /opt/cloudera/parcels/CDH/lib/hbase/hbase-server.jar,\
   /opt/cloudera/parcels/CDH/lib/hbase/hbase-mapreduce.jar,\
   /opt/cloudera/parcels/CDH/lib/hbase/hbase-shaded-miscellaneous.jar,\
   /opt/cloudera/parcels/CDH/lib/hbase/hbase-shaded-protobuf.jar,\
   /opt/cloudera/parcels/CDH/lib/hbase/hbase-protocol-shaded.jar,\
   /opt/cloudera/parcels/CDH/lib/hbase/hbase-protocol.jar,\
   /opt/cloudera/parcels/CDH/lib/hbase/hbase-protocol-shaded.jar,\
   /opt/cloudera/parcels/CDH/lib/hbase/hbase-shaded-netty.jar,\
   /opt/cloudera/parcels/CDH/lib/hbase/hbase-zookeeper.jar,\
   /opt/cloudera/parcels/CDH/jars/htrace-core-3.1.0-incubating.jar,\
   /opt/cloudera/parcels/CDH/lib/hbase/hbase-annotations.jar

9. Run the following code after launching the spark-shell:
   

   val df = spark.read.format("org.apache.hadoop.hbase.spark").option("hbase.columns.mapping", "id STRING :key, name STRING :p:name, email STRING p:email, age STRING p:age").option("hbase.table", "person").option("hbase.spark.use.hbasecontext", false).load()
   df.show(truncate=false)

   The output of the above command:
   

   scala> df.show(truncate=false)
   +---+----+---------------+---+
   |age|name|email |id |
   +---+----+---------------+---+
   |25 |1 |ranga@gmail.com| |
   +---+----+---------------+---+

Thanks for reading this article. I hope you have enjoyed it.