Since you brought up this blog, there are 3 things you need to know. 1. Authentication, 2. User/Group Mapping and 3. Authorization
1. For authentication, there is no alternative for Kerberos. Once your cluster is Kerberized, you can make it easier for certain access path by using AD/LDAP. Example, access to HS2 via AD/LDAP authentication or accessing various services using Knox.
2. Group mapping can be done in 3 ways. One as the blog says, where you lookup AD/LDAP to get the groups for the users. Second is to materialize the AD/LDAP users on the linux server using SSSD, Centrify, etc. Third is to manually create the users and groups in the linux env.All these options are applicable regardless whether you have Kerberos or not.
3. Authorization can be done via Ranger or using the natively supported ACL. Except Storm and Kafka, having Kerberos is not mandatory. Without reliable authentication, authorization and auditing is meaningless.
Common use case as yours: User A logs into the system with his AD credentials, HDFS or Hive ACL's kicks in for authorization.
You have to qualify "system". Which system are you logging in? Only HS2 and Knox allows you to login via AD/LDAP. If you are planning to do that, then you have to setup a very tight firewall around your Hadoop cluster. Absolutely no one should be able to connect to the NameNode, DataNode or any other service port from outside the cluster, except to the JDBC port of HS2 or Knox port. If you can setup this firewall, then all business users will be secure even if don't kerberize your cluster. However, any user who has shell login/port access to edge node/cluster or able to submit a custom job in the cluster will be able to impersonate anyone.
Setting up this firewall is not a trivial thing. Even if you do, there will be users who will need access to the cluster. There should be limited number of such users and these users should be trusted. And you should not let any un-approved job running within the cluster.
If the customer is okay with all the "ifs" and comfortable with limited number of super admin users, then yes you can have security without Keberos.
