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change a configuration ,then the cm will tell you must restart cluster

change a configuration ,then the cm will tell you must restart cluster

Contributor

HI:

 

Our company has a cloudera cluster,the cluster is online,and there are so many tasks all the time. But if I change a configuration about hdfs or other service,cloudera manager will tell you to restart all services on the cluster.you know,I will influence the online task.

 

 It bothers me so many time.

 

 

rube

 

6 REPLIES 6

Re: change a configuration ,then the cm will tell you must restart cluster

Master Collaborator

@rube I understand your frustration, it is not always convenient to restart services in a production cluster.  This is why we introduced the "Rolling Restart" feature in our Enterprise version of Cloudera Manager.  It is not possible to cause the various JVMs to reload their runtime configs to pick up your new properties, so a restart is necessary.  The rolling restart allows you to restart all the necessary JVMs while maintaining cluster uptime overall.  Sure, some jobs may need to be restarted still, but this is less disruptive than complete downtime.

Re: change a configuration ,then the cm will tell you must restart cluster

Contributor

Thanks very much,I do understand.

Re: change a configuration ,then the cm will tell you must restart cluster

Contributor
e~~,when add a new node to apache hadoop,just hadoop dfsadmin -refreshNodes will be ok,why cdh can not?

Re: change a configuration ,then the cm will tell you must restart cluster

Contributor

@clint, when add a new node to apache hadoop,just hadoop dfsadmin -refreshNodes will be ok,why cdh can not?

Re: change a configuration ,then the cm will tell you must restart cluster

Super Guru

Hi,

 

-refreshnodes only updates the hosts and exclude files.  Cloudera Manager does have this feature as explained here:

 

http://www.cloudera.com/content/cloudera/en/documentation/core/latest/topics/cm_mc_start_stop_cluste...

 

Depending on what you change, a restart or refresh may be required.  

 

Ben

Highlighted

Re: change a configuration ,then the cm will tell you must restart cluster

Note that sometimes topology is not actually refreshable. See https://issues.apache.org/jira/browse/HADOOP-8292