question Re: downtime for addition of nodes in Archives of Support Questions (Read Only)

downtime for addition of nodes

arunpoy — Wed, 21 Dec 2016 10:19:11 GMT

want to add a few nodes to a running cluster. does it require any down time and will the running jobs get affected?

Re: downtime for addition of nodes

bandarusridhar1 — Wed, 21 Dec 2016 11:17:16 GMT

No downtime is required for simple adding nodes for just DN, NM and other components. Even for adding client node(Edge node) doesn't require any downtime.

Re: downtime for addition of nodes

TimothySpann — Wed, 21 Dec 2016 11:42:51 GMT

https://community.hortonworks.com/questions/31915/adding-new-node-to-cluster.html

https://docs.hortonworks.com/HDPDocuments/HDP2/HDP-2.5.0/bk_administration/content/ref-4303e343-9aee-4e70-b38a-2837ae976e73.1.html

Re: downtime for addition of nodes

xwang — Thu, 22 Dec 2016 06:03:39 GMT

Basically, adding nodes (hosts) requires no downtime and will not affect running jobs at all.

Btw, you may try to do this by Ambari Add Hosts function. Scenario:

1. Go to Ambari Hosts page.

2. Click on Actions button located on the top left of this page.

3. Select "Add New Hosts " option.

You will see a wizard which will guide you through the whole process, you can add hosts with any slaves (DataNode, NodeManager, clients .etc) installed on them.

Hope this helps 🙂

Re: downtime for addition of nodes

cstanca — Thu, 22 Dec 2016 11:00:33 GMT

@ARUN

As @Xi Wang responded and suggested. I assess her response as appropriate. Please see also doc link (assuming you use Ambari 2.1.1.0, change to the proper link if you use an earlier version):

http://docs.hortonworks.com/HDPDocuments/Ambari-2.1.1.0/bk_Ambari_Users_Guide/content/_adding_hosts_to_a_cluster.html

Also, keep in mind that only new data will use the new data nodes, unless you execute rebalance hdfs command, then you have a distribution of all the data across all data nodes. Default threshold is 10, but you could change it to your desired threshold. You may want to execute it during off-peak hours.