If a Qumulex Gateway loses internet access, you can still connect and use the system using the following method. This will allow you to connect and view the Gateway from the Local Network while the Internet is down. It is highly recommended that you configure a DHCP Reservation for the network connected to the internet (or statically assign it if needed) if you are going to use this feature.
To set this up there are a few steps that need to happen. Generically, they are as follows.
- An offline login needs to be created for each User who may require it individually.
- Either a DNS Server configuration or a localhost configuration will need to be made allowing a unique 'offline url' to be used in an offline situation.
- To use this feature once it is setup, the client must be on the same general local network as the Gateway.
The first thing you need to do is setup a unique Offline Password for your User. This is done on a per-user basis. Since the goal of this is to access the system while there is no internet, the normal cloud authentication will be unavailable. If your system is on the latest version you may see an alert icon indicating actions needed similar to the image below.
Click on the Settings Link, and then select Offline Access. The first thing you will be presented with (if it is not set yet) is a Create Password Button.
Clicking "Create Password" will move you to the bottom of the page in the proper creation spot.
Be sure you remember your password created for this. If you lose internet and need to login but do not remember this password, it cannot be reset in that moment.
Once that is done you should have a confirmation that let's you know it is complete. If you need to change the password for any reason while the system has internet connectivity, you may do so from the same location. 
Now you need to find out, or decide which offline configuration method is achievable in your scenario.
1. Configuring your local DNS Server at the install site.
2. Configuring the localhosts file manually on each local client that may need access during an offline event.
In either scenario it is important to ensure that your Scope is set correctly. (https://www.qumulex.com/kb/setting-your-scope) . This is mostly relevant if you are an Integrator configuring on behalf of a customer, or if you have more than one Gateway installed at the same physical location. We added a Reset Scope and Change Scope button here for your convenience.
Click Download DNS List to receive a text file with a list of available Gateways at your current Scope that contains the Name, Hostname, and IP address. In the example above there is only one server available at the scope currently selected. If you see "No data for table" then the Scope you have selected (or are currently in) does not contain the actual Gateway location. If you cannot get this to populate please contact the person who Administers your system.
The preferred setup would be Option 1. In most cases this is something the local IT crew will be able to setup for you. If you are the person with this access, simply Update your DNS Server(s) to include the IP(s) and hostname(s) provided in the downloaded file to allow internal access for anyone using the proper URL from within the local network.
Option 2 is a per computer (and local OS User) configuration.
In Windows you will need to edit your localhost file to include the static DNS configuration.
Instructions linked HERE.