USG FLEX H Series [uOS] - how upgrade/update USG FLEX H Series Firewall

This article outlines the standard procedure for updating the firmware on the USG FLEX H-Series firewall, encompassing both the device initialization phase and updates on a pre-configured device. We will explore various methods, including updating during the device initialization process, utilizing cloud-based updates, employing FTP for updates, using a pre-downloaded update file from the global site, and scheduling updates. It is strongly advised to install the latest firmware version for optimal performance and security. An important difference with the H-Series upgrade is that both sections are now updated automatically, eliminating the need to update them separately as was required with the ATP/FLEX/VPN models, which greatly simplifies the upgrade process.

Note: Always keep a backup copy of your configuration so that you can quickly restore your firewall settings if unexpected situations arise during the installation of updates. We strongly recommend making a systematic backup of your device's configuration file.  How to save the configuration can be found at the link:  USG FLEX H Series [Firewall] - how to backup/restore a configuration file

Disclaimer!  This article offers a general overview of the series and may not apply uniformly to every model, software/firmware version. Before purchasing or using the device, please consult the model/version-specific documentation or reach out to technical support for accurate information.

Updating the device at first start-up

Note: Please be advised that certain USG FLEX H series devices, released during the early production phase and shipped with factory firmware version v6.29, require an additional step before they can be put into operation.

Before upgrading to the latest available firmware version, these devices must first be updated to version v1.08. After that, you can proceed directly to the latest firmware version, without the previously recommended intermediate update to v1.10.

Upgrade procedure for devices with firmware version v6.29:

1. Use the initial setup wizard to upgrade the firmware from v6.29 to v1.08

2. Then, upgrade the firmware directly to the latest available version

⚠️ Disclaimer: This information provides a general overview of the series and may not apply to every model. Before using the device, please refer to the model-specific documentation or contact technical support for accurate information.

Models: USG FLEX 100H/ 200H/ 200HP/ 500H/ 700H

In Step.1 and Step.2, the system will check your WAN Internet connection and synchronize the current Date & Time with the NTP server.

In Step.3, the system will automatically verify and download the firmware from the cloud. Please ensure that your Internet network is connected; the system will then proceed to automatically upgrade the firmware to version 1.08 patch1

Once your system is successfully upgraded, login and the firmware wizard will be performed again. In version 1.08p1, the wizard has only two steps: The Step.1 checks the Internet network connection state once again.

The Step.2 it will auto-downloads firmware from cloud, and the system will then proceed to automatically upgrade the firmware to version 1.10.

Firmware update via WEB GUI

• Connect to the USG FLEX H interface through your web browser. Ensure you have administrator privileges.
• In the USG FLEX H interface, navigate to the section for "Firmware/File Manager" This will typically be under a 'Maintenance' section

There are three options for updating the device firmware via the web interface:

1. Local update - using a previously downloaded file. Visit the Zyxel Download Library for the latest firmware version.
2. Cloud Firmware Upgrade - initiated by clicking the 'Perform Upgrade' button.
3. Scheduled Upgrade - set a device upgrade schedule for automatic execution.

Note: After the firmware upload is complete, the device will require a reboot. This process may take a few minutes. Once the device has restarted, log back into the web interface. Check the firmware version to ensure the upgrade was successful​

Firmware update via FTP

The process of updating the device via FTP is straightforward. Ensure you are on the same local network as the device. Open Explorer or any application supporting the necessary access (for our example, we will use Explorer).

• Visit the Zyxel Download Library and download the latest firmware version.
• Enter the device address in the following format: ftp://192.168.168.1
• In the window that appears, enter the username and password for your USG FLEX H

• Move the previously downloaded update file into the folder. The file must be in ".bin" format as shown in the figure below.

Once the file is copied, the update process will start automatically. Monitor the progress through the PWR/SYS LED on the device, which should start blinking. It's crucial not to power off the device during the update. Once the LED stops blinking and remains continuously lit, the update process is complete

Upgrade Failed Recovery (1.10)

If you manually upgrade the firmware to 1.10 and encounter issues preventing your Firewall from booting up successfully, you can follow these steps to recover your system.

Step.1 Connect the console to the device and enter debug mode after restarting the device.
When you see "Press any key to enter debug mode within 3 seconds," press any key to enter debug mode. Then set command line, use partition 1 to restart the device.

> atcd 1
> atgo

Step.2 Wait for the device to boot up, open your browser, and enter https://192.168.168.1.

Log in to the GUI and please using the firmware wizard to upgrade to uOS 1.08 Patch 1 firmware first, and then proceed with the upgrade to uOS1.10 firmware.