Ambari + change the parameters of the ambari services by auto proccess

[#1]

I performed the following steps in order to update some values in Ambari GUI

we have - Ambari cluster GUI ( Version 2.5.0.3 )

lets say we want to change the parameter value ( from YARN service )

yarn.scheduler.minimum-allocation-mb : from 11776 to 11700

so we create first the following blueprint.json file as the following: ( under /tmp )

curl  -u admin:admin -H "X-Requested-By: ambari" -X GET http://101.64.36.20:8080/api/v1/clusters/HDP01?format=blueprint -o /tmp/HDP01_blueprint.json

we delete the existing blueprint from ambari cluster as the following:

curl  -u admin:admin -H "X-Requested-By: ambari" -X DELETE http://101.64.36.20:8080/api/v1/blueprints/HDP01

and finally we update the new blueprint.json back to ambari cluster as the following

curl -u admin:admin -H "X-Requested-By: ambari" -X POST  http://101.64.36.20:8080/api/v1/blueprints/HDP01?validate_topology=false -d @/tmp/HDP01_blueprint.json

to take affect we restart the ambari server

ambari-server restart

we access to the ambari GUI to see the new value but the old value appears

please advice what is wrong with my steps?

the target of my procedure is to replace the values from the ambari cluster by reconfigure the blueprint.json file

[#2]

I just thinking to do the same steps on a other ambari cluster , do you sure that this steps are safe , or maybe you already test it on your LAB?