I am newbie to Cassandra. I wanted to install cassandra-0.8.4 on 3 nodes and to run Map/Reduce job that uploads data from HDFS to Cassandra.
I have installed Cassnadra on 3 nodes lab02(199.168.0.2),lab03(199.168.0.3) & lab04(199.168.0.4) respectively and can create a keyspace & column family and they got distributed across the cluster.
When I run my map/reduce program it ended up with "UnknownHostException". the same map/reduce program works well on single node cluster.
Here are the steps which I have followed.
- cassandra.yaml details
lab02(199.168.0.2): (seed node)
auto_bootstrap: false seeds: "199.168.0.2" listen_address: 199.168.0.2 rpc_address: 199.168.0.2
lab03(199.168.0.3): auto_bootstrap: true seeds: "199.168.0.2" listen_address: 199.168.0.3 rpc_address: 199.168.0.3
lab04(199.168.0.4): auto_bootstrap: true seeds: "199.168.0.2" listen_address: 199.168.0.4 rpc_address: 199.168.0.4
2. When I run my map/reduce program it ended up with "UnknownHostException"
Error: java.net.UnknownHostException: /199.168.0.2 at java.net.Inet6AddressImpl.lookupAllHostAddr(Native Method) at java.net.InetAddress$1.lookupAllHostAddr(InetAddress.java:849) at java.net.InetAddress.getAddressFromNameService(InetAddress.java:1200) at java.net.InetAddress.getAllByName0(InetAddress.java:1153) at java.net.InetAddress.getAllByName(InetAddress.java:1083) at java.net.InetAddress.getAllByName(InetAddress.java:1019) at java.net.InetAddress.getByName(InetAddress.java:969) at org.apache.cassandra.client.RingCache.refreshEndpointMap(RingCache.java:93) at org.apache.cassandra.client.RingCache.(RingCache.java:67) at org.apache.cassandra.hadoop.ColumnFamilyRecordWriter.(ColumnFamilyRecordWriter.java:98) at org.apache.cassandra.hadoop.ColumnFamilyRecordWriter.(ColumnFamilyRecordWriter.java:92) at org.apache.cassandra.hadoop.ColumnFamilyOutputFormat.getRecordWriter(ColumnFamilyOutputFormat.java:132) at org.apache.cassandra.hadoop.ColumnFamilyOutputFormat.getRecordWriter(ColumnFamilyOutputFormat.java:62) at org.apache.hadoop.mapred.ReduceTask.runNewReducer(ReduceTask.java:553) at org.apache.hadoop.mapred.ReduceTask.run(ReduceTask.java:408) at org.apache.hadoop.mapred.Child.main(Child.java:170)
Here are the config line for map/reduce.
job4.setReducerClass(TblUploadReducer.class );
job4.setOutputKeyClass(ByteBuffer.class);
job4.setOutputValueClass(List.class);
job4.setOutputFormatClass(ColumnFamilyOutputFormat.class);
ConfigHelper.setOutputColumnFamily(job4.getConfiguration(), args[1],args[3] );
ConfigHelper.setRpcPort(job4.getConfiguration(), args[7]); // 9160
ConfigHelper.setInitialAddress(job4.getConfiguration(), args[9]); // 199.168.0.2
ConfigHelper.setPartitioner(job4.getConfiguration(), "org.apache.cassandra.dht.RandomPartitioner");
Steps which I have verified are
- There is a passwordless ssh has been configured b/w lab02,lab03 &lab04. All the nodes can ping each other with out any issues.
- When I ran "InetAddress.getLocalHost()" from java program on lab02 it prints "lab02/199.168.0.2".
- When I over looked "o/p" of bin/cassandra it prints couple of messages and under InetAddress field "/199.168.0.3" etc. Here it does not print "hostname/IP". Is that problem?
Kindly help me to resolve above issue.
Regards, Thamizhannal
