我将cassandra安装在多节点集群中，逻辑上分为两个数据中心，
bc1-分析应用程序在这些节点上运行bc2-ui应用程序在这些节点上运行
我创建了一个键空间，

CREATE KEYSPACE ks23 WITH replication = {
  'class': 'NetworkTopologyStrategy',  'BC2': '3'
};

当我尝试使用在bc1节点上运行的pig脚本从上面的键空间访问表数据时，我得到了这个错误，

at org.apache.pig.backend.hadoop.executionengine.mapReduceLayer.PigInputFormat.getSplits(PigInputFormat.java:288)
        at org.apache.hadoop.mapred.JobClient.writeNewSplits(JobClient.java:1054)
        at org.apache.hadoop.mapred.JobClient.writeSplits(JobClient.java:1071)
        at org.apache.hadoop.mapred.JobClient.access$700(JobClient.java:179)
        at org.apache.hadoop.mapred.JobClient$2.run(JobClient.java:983)
        at org.apache.hadoop.mapred.JobClient$2.run(JobClient.java:936)
        at java.security.AccessController.doPrivileged(Native Method)
        at javax.security.auth.Subject.doAs(Subject.java:415)
        at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1232)
        at org.apache.hadoop.mapred.JobClient.submitJobInternal(JobClient.java:936)
        at org.apache.hadoop.mapred.JobClient.submitJob(JobClient.java:910)
        at org.apache.hadoop.mapred.jobcontrol.Job.submit(Job.java:378)
        at org.apache.hadoop.mapred.jobcontrol.JobControl.startReadyJobs(JobControl.java:247)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:606)
        at org.apache.pig.backend.hadoop20.PigJobControl.mainLoopAction(PigJobControl.java:157)
        at org.apache.pig.backend.hadoop20.PigJobControl.run(PigJobControl.java:134)
        at java.lang.Thread.run(Thread.java:744)
        at org.apache.pig.backend.hadoop.executionengine.mapReduceLayer.MapReduceLauncher$1.run(MapReduceLauncher.java:259)
Caused by: java.io.IOException: Could not get input splits
        at org.apache.cassandra.hadoop.AbstractColumnFamilyInputFormat.getSplits(AbstractColumnFamilyInputFormat.java:197)
        at org.apache.pig.backend.hadoop.executionengine.mapReduceLayer.PigInputFormat.getSplits(PigInputFormat.java:274)
        ... 20 more
Caused by: java.util.concurrent.ExecutionException: java.io.IOException: failed connecting to all endpoints
        at java.util.concurrent.FutureTask.report(FutureTask.java:122)
        at java.util.concurrent.FutureTask.get(FutureTask.java:188)
        at org.apache.cassandra.hadoop.AbstractColumnFamilyInputFormat.getSplits(AbstractColumnFamilyInputFormat.java:193)
        ... 21 more
Caused by: java.io.IOException: failed connecting to all endpoints
        at org.apache.cassandra.hadoop.AbstractColumnFamilyInputFormat.getSubSplits(AbstractColumnFamilyInputFormat.java:311)
        at org.apache.cassandra.hadoop.AbstractColumnFamilyInputFormat.access$200(AbstractColumnFamilyInputFormat.java:61)
        at org.apache.cassandra.hadoop.AbstractColumnFamilyInputFormat$SplitCallable.call(AbstractColumnFamilyInputFormat.java:230)
        at org.apache.cassandra.hadoop.AbstractColumnFamilyInputFormat$SplitCallable.call(AbstractColumnFamilyInputFormat.java:215)
        at java.util.concurrent.FutureTask.run(FutureTask.java:262)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
        at java.lang.Thread.run(Thread.java:744)

相同的脚本可以很好地用于两个数据中心中的其他键空间