You can use the Server app to manually override default user access to services. This isn’t recommended. Whenever possible, use Server’s Access lists to manage service access.
Use the Server app to manually restrict user access to services listed in the Server app, with the exception of Web and Wiki services. Web and Wiki services have more customizable access control.
For websites, you can limit access on a per-site level. For example, if your server is hosting two websites, www.example1.com and www.example2.com, you can give users access to www.example1.com but not to www.example2.com.
Wikis have their own access controls, so you can restrict who’s allowed to create wikis. When you create a wiki, you can designate others as administrators. Wiki administrators can choose who has access to the wiki and which users can read and write or just read wiki content.
Select Users in the Server app sidebar.
Control-click the user, then choose Edit Access to Services.
To apply access to several users, hold down the Command key while selecting users, Control-click a selected user, then choose Edit Access to Services.
In the dialog that appears, click Manage Service Access, then read the warning, then confirm.
Select the checkboxes for services you want the user to access, then click OK.
If you’re not hosting network accounts, the checkboxes for services you’re providing are selected and dimmed. If you want to manage services, you must click Manage Service Access to select the checkboxes for services you want users to access.