how to stop all data node services by REST API

[#1]

hi all

is it possible to stop only the data node services on all datanodes machines?

in the following example , we can see example of datanode service from worker machine

and the 3/3 datanodes services

example of the full services on each worker machine:

[#2]

@mike_bronson7 
You can try this.

1. Get the list of DataNode hosts. When you can get like following:

# curl -s -u admin:admin -H "X-Requested-By: ambari" -X GET http://$AMBARI_FQDN:8080/api/v1/clusters/CLUSTER_NAME/services/HDFS/components/DATANODE | grep 'host_name'

2. The. run the following kind of API call by passing the hostnames where the datanode are running. Suppose datanodes are running on 3 Hosts with name "dn1.example.com, dn2.example.com, dn3.example.com" then you can do the following:

# curl -s -u admin:admin -H "X-Requested-By: ambari" -X PUT -d '{"RequestInfo":{"context":"Stop DataNodes","operation_level":{"level":"SERVICE","cluster_name":"$CLUSTER_NAME"},"query":"HostRoles/component_name=DATANODE&HostRoles/host_name.in(dn1.example.com,dn2.example.com,dn3.example.com)&HostRoles/maintenance_state=OFF"},"Body":{"HostRoles":{"state":"INSTALLED"}}}' "h ttp://$AMBARI_FQDN:8080/api/v1/clusters/$CLUSTER_NAME/host_components"

.
Please replace all $CLUSTER_NAME and $AMBARI_FQDN accordingly.

[#3]

Dear Jay , give me some time I will verify the API on my cluster

is it possible to use the API from your answer , to stop all NodeManager on all workers machines?

[#4]

Dear Jay

lets say we want to set instead

dn1.example.com,dn2.example.com,dn3.example.com

we want to set variable

all_DN_machines=dn1.example.com,dn2.example.com,dn3.example.com

so the val - $all_DN_machines will be instead of all real machines - is it possible ? 

[#5]

@mike_bronson7 
Similar thread: 
https://community.cloudera.com/t5/Support-Questions/set-Variable-in-ambari-rest-API/m-p/294856/highl...

[#6]

Dear Jay - can we use this API to stop all NodeManager  on all workers machines ? if yes , can you show me please how ?