hadoop BlockMissingException

问题:

I am getting below error:

Diagnostics: org.apache.hadoop.hdfs.BlockMissingException: Could not obtain block: BP-467931813-10.3.20.155-1514489559979:blk_1073741991_1167 file=/user/oozie/share/lib/lib_20171228193421/oozie/hadoop-auth-2.7.2-amzn-2.jar
Failing this attempt. Failing the application.

Although I have set replication factor 3 for /user/oozie/share/lib/ directory. All the jars under this path are available on 3 datanode but few jars are missing. Can any body suggest why this is happening and how to prevent this.

回答1:

I was getting the same exception while trying to read a file from hdfs. The solution under the section "Clients use Hostnames when connecting to DataNodes" from this link worked for me: https://hadoop.apache.org/docs/r2.7.2/hadoop-project-dist/hadoop-hdfs/HdfsMultihoming.html#Clients_use_Hostnames_when_connecting_to_DataNodes

I added this XML block to "hdfs-site.xml" and restarted the datanode and namenode servers:

<property>
    <name>dfs.client.use.datanode.hostname</name>
    <value>true</value>
    <description>Whether clients should use datanode hostnames when
      connecting to datanodes.
    </description>
</property>