USG FLEX H Series [uOS] - Initial Setup USG FLEX H Series Firewall

This article provides a clear and concise walkthrough for setting up and configuring your Zyxel USG FLEX H Series firewall. While this guide does not cover advanced configurations, it will help you complete the initial setup, establish internet connectivity, and register the device properly.

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.

Disclaimer! This article provides a general overview of the series and may not be applicable to every model uniformly. Before purchasing or using the device, please consult the model-specific documentation or contact technical support for accurate information.

USG FLEX H Series [Firewall] - upgrade/update procedure

Initial Setup

Before we begin the internet (WAN) setup on the ZLDL router, the following steps need to be completed.

• Unpack the appliance.
• Connect the power supply (power cord)
• Please wait for the device to boot up the device ON (it takes 2-3 minutes to power up)
• Connect a computer to a LAN port on the device, P5
• Connect the DSL/Cable modem to the device, P1

Note: For the initial startup of the device, it is necessary that the device is connected to the Internet, as one of the first mandatory steps is to configure the WAN (Internet connection). It is also important to note that after configuring access to the Internet, the mandatory step is to register your device. 

Zyxel Account

If you don't have a Zyxel account, you can create one using the link: Create Zyxel Account

Video tutorial - One Login for All Zyxel Platforms with Single Sign-On

Accessing the WebUI

To access the USG FLEX H web configuration page, open a web browser on your computer (e.g., Internet Explorer, Mozilla Firefox, Google Chrome).  On the address ba,r please type http://192.168.168.1 to access the WebUI. The Login screen appears.

Note: Default login: admin/password, as shown on the device sticker. If no sticker is present, the default password may be 1234.

Note: The value in this field is invalid. It can consist of 4-63 characters. The valid characters are [0-9][a-z][A-Z]['(){}<>^`+/:!*#@&=$\.~%,|;-"]. Space is also not allowed. 

Note:  If the default password has been changed, use the new password to log in.  If this is the first time setting up the device and it is not accepting the "1234" password or password, as shown on the device sticker, please press the RESET button on the device (located on the front panel) and hold it down for 10-15 seconds

WAN Setup Wizard

• Connect to Internet step - "The initial setup wizard will appear the first time you log in to the USG FLEX H WebUI. Simply follow the prompts to configure the WAN port connection.  In the first step, you can select the interface type, DHCP, Static, PPPoE, and specify the WAN port, which can be Port P1 or P2.

Click 'Next' to proceed to the next step.

• System Time step - the date, time, and time zone settings will be set automatically. You can change it later in the device menu.

Click 'Next' to proceed to the next step.

Device Registration 

Registering your Zyxel device is required to access the web interface, activate security services, and receive firmware updates. Make sure your Zyxel Device can access the Internet. Click Register to go to Nebula Control Centre (NCC) to register your Zyxel Device. NCC is an Internet portal that enables you to manage and monitor groups of Zyxel devices within organisations.

• You can just enter your login details if you have an account. Otherwise, you can create a new one.

• To register your USG FLEX H firewall with Nebula, please select an Organization and a Site under your authority, or create new ones. You organize Zyxel devices in Nebula into Organizations, for example, "YourCompany" or "YourClient", and Sites, for example, "London Branch" or "Factory".

• Please review your device & license information and follow the prompts in the registration menu to complete the registration of the new device. After all, steps have been completed, you will return to the "Device Registration" step and the registration status will change to "Registered".

• The registration process may take a few minutes. After that, you will see a confirmation that the registration was successful.

Click 'Next' to proceed to the next step.

License Summary

• License Summary step - the next step automatically activates all services to which you have a subscription.
• Click 'Next' to proceed to the next step.

Auto Subnet Planning Setup

• At this step, you can choose whether Nebula should automatically update the subnets for interfaces ge3 and ge4 to avoid IP conflicts between VPN devices in the same organisation.

• Options:

• Yes – Nebula will assign new subnets:
  • ge3: from 192.168.168.1/24 → 192.168.176.1/24
  • ge4: from 192.168.169.1/24 → 192.168.177.1/24

• No – Keep the current default subnets.

• Click Finish to apply the selected settings and complete the wizard.

After Clicking "Finish"

1. Click OK to apply new subnets.

2. Wait 10 seconds (sometimes it takes longer, just wait), then reconnect your cable or Wi-Fi.

3. You will be redirected to the new login page.

   • If not, open it 192.168.176.1 manually in your browser.

4. Click "Connect to New Network" to continue.

Please note that the device's IP address has changed.

Finish step - Click Finish to exit the wizard.

Troubleshooting

If you encounter issues during the 'Connect to the Internet' step, please review your settings:

• Verify the interface type is correctly configured. Ensure that you are obtaining an IP address automatically, or, if necessary, specify it manually.
• Confirm the port to which the Internet cable is connected—whether it's P1 or P2. Ensure that you have selected the appropriate port."

Troubleshooting Internet Connectivity Issues

If you're experiencing internet connectivity problems, follow these steps to diagnose and resolve the issue:

1. Verify ISP Parameters and IP Address Assignment:
   • Check your ISP settings and ensure they match the information provided by your service provider.
   • Confirm that the IP address assignment settings are correctly configured.
2. Check WAN Connection:
   • Ensure that P1 (WAN Port) on the USG FLEX H is properly connected to your DSL or Cable modem.
3. Reset Cable Modem Cache (for cable modem users only):
   • Note: If your cable modem also provides telephone service, do not proceed with this step; contact your ISP for assistance.
   • You have three options to reset the cable modem:
     • Press and hold down the RESET button for 15 seconds to clear the cache.
     • If the modem doesn't have a RESET button, power it down for 5 minutes. Remove the power cable and battery backup (if applicable).
     • Contact your cable internet provider to request a modem cache reset from their end.
4. Verify DSL Modem Mode (for DSL modem users):
   • Many DSL modems function as modem/router combinations. It's recommended to contact your internet service provider and request that they set the modem to bridge mode for optimal compatibility with your Firewall.
5. Reboot the Firewall:
   • Restart your USG FLEX H device to refresh its settings
6. Contact Zyxel Technical Support:
   • If the issue persists, you can reach out to Zyxel Technical Support for further assistance.