Using Software Update Server
Summary:

The simple way to configure a client to point to your Software Update server is using the following Terminal command on your client:

sudo defaults write /Library/Preferences/com.apple.SoftwareUpdate CatalogURL http://su.domain_name.com:8088/index.sucatalog


Replace su.domain_name.com with your server's fully qualified domain name as specified in Server.app. You can find your FQDM by going to Server.app → [server name] → Access: Host Name:



You can change your FQDM by clicking the Edit… button on the right.



More detail:


Set a host name by going to Server.app → [server name] → Access: Host Name → Edit…. If you wish to access your server over the internet without VPN, choose Domain Name. Otherwise, choose one of the Local Network options.


Switch on the Software Update service.


Once the service has started, you can find the FQDM in the Access section.


Using this FQDM, you can find your CatalogURL by substituting this into the following URL:

http://[FQDM]:8088/index.sucatalog


For example, if my FQDM is reported under the Access section as server.example.private, my Software Update catalog would be located at http://server.example.private:8088/index.sucatalog.
On your clients, you can configure them by running the following Terminal command:

sudo defaults write /Library/Preferences/com.apple.SoftwareUpdate CatalogURL [your-catalogURL]


Replace [your-catalogURL] with the URL that you got from step 4.


You can revert your settings by running the following Terminal command:

sudo defaults delete /Library/Preferences/com.apple.SoftwareUpdate CatalogURL


Alternatively, you can use Profile Manger to provide OTA configuration using the Custom Settings section of your configuration profile.