Hi Kellen! The first part of the configuration is a good indication of which service you need to restart. Unfortunately the only way to be completely sure is to read the codez. e.g. most hdfs configuration is mapped to variables in DFSConfigKeys
$ find . -name *.java | grep -v test | xargs grep "dfs.datanode.handler.count" ./hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DFSConfigKeys.java: public static final String DFS_DATANODE_HANDLER_COUNT_KEY = "dfs.datanode.handler.count"; Looking at where this is used: $ find . -name *.java | grep -v test | xargs grep DFS_DATANODE_HANDLER_COUNT_KEY ./hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/DataNode.java:import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_DATANODE_HANDLER_COUNT_KEY; ./hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/DataNode.java: getConf().getInt(DFS_DATANODE_HANDLER_COUNT_KEY, ./hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DFSConfigKeys.java: public static final String DFS_DATANODE_HANDLER_COUNT_KEY = "dfs.datanode.handler.count"; Cheers, Ravi On Thu, Sep 7, 2017 at 10:46 AM, Kellen Arb <[email protected]> wrote: > Hello, > > I have a seemingly simple question, to which I can't find a clear answer. > > Which services/node-types must be restarted for each of the configuration > properties? For example, if I update the 'dfs.datanode.handler.count' > property in the `hdfs-site.xml` configuration file, which services must be > restarted? Can I get away with only restarting `datanodes`, or do I also > need to restart `journalnodes` and/or `namenodes`, `zkfc` etc. > > Just looking for clarification on this issue, though it seems that > generally the advice is "restart everything”? > > Thank you, > Kellen Arb > --------------------------------------------------------------------- > To unsubscribe, e-mail: [email protected] > For additional commands, e-mail: [email protected] > >
