How can I flash/install custom firmware on the Vodafone Connect router (HHG2500)?

[jivanpal]

I am not a Vodafone customer, but have purchased a Vodafone Connect Wi-Fi router (model number HHG2500) on eBay that I wish to use as a wired-only dual-stack (Pv4+IPv6) gigabit router with two subnets behind it, with one of the subnets having a separate Wi-Fi access point connected to it. Having now explored the pre-installed firmware, it might suffice for my needs, but my intention was to install OpenWrt on it, following this wiki guidance., for more advanced configuration (e.g. firewall rules, port forwarding, address translation, and traffic monitoring).

However, the pre-installed firmware doesn't seem to expose an option to install firmware manually from a binary file of my choice, as is shown in a screenshot on that wiki page for the Vox2.5 router. Instead, my firmware page looks like this:

I have tried following guidance on how to put various Sercomm routers into recovery/upgrade mode (by booting them whilst the reset button is depressed), but this doesn't seem to be working for me. It's possible that I'm doing this incorrectly, but it just boots normally and I can access the Vodafone-branded admin UI as normal, as shown in the screenshot above. If anyone can offer any guidance on how I can install the desired firmware on this device, that would be greatly appreciated.

— Jivan

[Ripshod]

People have been trying to do this for years. Without the ability to hack the CFE you won't get anywhere, and no-one has done it yet.

Why would you want to use it anyway? Firstly, it's made by Huawei. Secondly, it's old tech first gen wifi 5. Thirdly, there's no secure firmware available.

Even if you could, would you? 

[jivanpal]

Like I said, I just want a cheap device with 3 gigabit Ethernet ports that can run something like OpenWrt or OpnSense. I've been looking at thin clients and the like, but the market for those is relatively expensive at the moment, whereas I was able to get this Vodafone router for £5.50. I have no interest in the device's WiFi capabilities (it's going to be disabled and OpenWrt doesn't support its Broadcom chip anyway) or the branding; nothing is wrong with Huawei, and I find it puzzling that that seems to be a primary objection of yours.

"No one has done it yet"? There are freely available tools for flashing firmware to Sercomm devices in recovery mode, I just can't seem to boot this device into that mode. There are also plenty of videos of people directly attaching a serial console to such devices in order to interact directly with the bootloader. That includes this device specifically.

"No secure firmware available"? There are up-to-date OpenWrt images available for this hardware, but I'm not an embedded systems guy and don't have the equipment or inclination to break open a router just to attach a serial console to it in order to hack it. I'd rather just spend an extra £20 on a TP-Link router that I know supports OpenWrt, but I thought I'd try this potentially cheaper option first, since the wiki guide suggests it should have easily been possible to flash firmware via the web GUI.

If anyone else sees this post and has any useful info, I'm still interested.

[Ripshod]

"I just can't seem to boot this device into that mode."

The CFE locks everything down. You'll never get past that lock.

Good luck.