This extension lets you put Magento 2 store in maintenance mode without a need to run a SSH command.
After you install the extension, go to Stores > Configuration > Goivvy LLC > Maintenance Mode and turn on Maintenance Mode.
This extension could come handy when you perform an upgrade or work on speed optimizations and customizations.
The extension will automatically whitelist your IP so that you could work on both frontend and backend while the store is in Maintenance Mode.
Contact a developer with any questions or feature requests.