@Mohammed Esoofally
Regarding your query: "Can 'n' users access a single node cluster at the same time? How do i create the user accounts?"
>> To create these accounts manually, you can use the following command on the host:
# useradd -G <groupname> <username>
https://docs.hortonworks.com/HDPDocuments/HDP2/HDP-2.6.4/bk_command-line-installation/content/create...
The above link shows some typical user accounts that are automatically available with the HDP installation however you can create as many users you want.
You can also use options available for group mapping is to use SSSD r one of the following services to connect the Linux OS with LDAP:
- Centrify
- NSLCD
- Winbind
- SAMBA
https://docs.hortonworks.com/HDPDocuments/HDP2/HDP-2.6.4/bk_security/content/setting_up_hadoop_group...