How to Create a non-root account with Administrator capabilities on ESX
To create a non-root account that has Administrator level privileges on ESX.
As per the ESX Server Configuration Guide:
To add a user to the Users Table.
Log in to the host using the vSphere Client, using the root userid.
Click the Local Users & Groups tab and click Users.
Right-click anywhere in the Users table and click Add to open the Add New User dialog.
Enter a login name, a user name, a numeric user ID (UID), and a password.
Specifying the user name and UID are optional. If you do not specify the UID, the vSphere Client assigns the next available UID.
Create a password that meets the length and complexity requirements. However, the ESX host checks for password compliance only if you have switched to the pam_passwdqc.so plug-in for authentication. The password settings in the default authentication plug-in, pam_cracklib.so, are not enforced. To allow a user to access the ESX host through a command shell, select Grant shell access to this user.
In general, do not grant shell access unless the user has a justifiable need. Users that access the host only through the vSphere Client do not need shell access.
To add the user to a group, select the group name from the Group drop-down menu and click Add.
To select the Permissions tab, also in the local host vSphere client session, and then:
Right click "Add Permissions"
select Administrator from the Assigned Role drop-down box
click Add to bring up a list of available users
select the user you added in Step 1 and click Add, then OK
At this point, you should now be able to login to the ESX host using that user, and the vSphere client.