Single Yarn node in HDP

[#1]

I installed HDP on 3 nodes and it seems that Yarn is running only in a single node and spark applications also run on 1 node only and work is not distributed on all nodes.

Where can I look to understand the issue?

[#2 · Accepted solution]

@Yair Ogen,

I guess you have only a single Node manager. You can always install the node managers in other nodes as well.

Click on Hosts -> Select the host you want to install the node manager -> Click Add -> Select Nodemanager

Thanks,

Aditya

[#3]

@Aditya Sirna

Thanks. Is it a problem to install node manager on all 3 nodes? I think that the auto-install process installed it on one of the nodes automatically. One would think that if the auto install only installed on one node - that's the way it should be, no?

Are 3 nodes enough for sandboxing or should we have at least 5 as recommended for zookeeper master election?

[#4]

@Yair Ogen

While installing the cluster, in the "Assign Slaves and Clients" page ambari will give an option to select the nodes where you want to install the Node managers. By default only a single node will be selected. You can select other nodes as well to install on them.

The no of node managers you want to install depends on no of factors (no of applications you want to run, memory used by apps etc)

Check this link for more info

https://community.hortonworks.com/questions/82861/how-many-node-managers-should-be-installed.html