Set a default request_pool for a user

[#1]

Is it possible to set a specific user or group to automatically use a specific request pool rather than setting it manually in each session?

[#2]

Never tried for specific group, but I think you can configure it in the Placement Rules in Impala Admission Control. For example I defined that if the user does not have his "personal" pool then use "pool1" as a default pool.

[#3]

Could you refer the below link , i belive this is what you are looking for .  Setting YARN user limit 

https://www.cloudera.com/documentation/enterprise/5-9-x/topics/cm_mc_resource_pools.html#concept_kht...