Friday 5 February 2010

FritzBox fritzed

MAC spoofing capability removed from latest firmware

I've been using an AVM FritzBox WLAN 7270 VoIP/Wi-Fi/Dect router for almost two years, and it's given me sterling service. But the other day I was messing around with the settings and managed to screw it up totally. I thought I had backed up the settings, but nope, I couldn't get back into the web GUI.

A factory reset seemed the only solution, but oddly the FritzBox has no hardware reset button. The only way to reset it is by plugging an analogue phone into one of the two phone ports and dialling a special code (the code is #991*15901590* if you're interested). Bizarre, but it worked. Well, sort of.

A few weeks ago a new firmware update (version 54.04.76) was installed, which offers some great new features such as a SIP proxy and support for 3G USB dongles. When I came to restart the router, it wouldn't connect to my ISP (Virgin Media) and I realised I'd forgotten to change the MAC address to clone that of a long-dead network card. With Virgin, your account is tied to one MAC address and changing it involves so much pain that it's not worth the bother.

But scouring the menus I couldn't find the setting anywhere. So I contacted AVM support via the contact form on the website, and the next morning got a reply . Turns out MAC address spoofing has been turned off in the new firmware, and the only way to get it back is to downgrade to version 54.04.67, which was attached to the email. Excellent service (I didn't tell them I was a journalist), but what a daft idea.

The good news is that the downgrade worked perfectly and I could change the MAC address. I then realised that when the new firmware was installed a few weeks ago, it must have retained the cloned MAC address as it was still connecting fine. So I updated back to 54.04.76 and it works fine.

I can't for the life of me understand why they've turned off MAC address cloning - practically every router I've ever seen has this feature. What it means for AVM is that any broadband users with a MAC-linked service wanting to buy a new FritzBox should ask first whether AVM will make the the old firmware available - at the moment it's not available to download on the website.

The other moral to this tale is before you change your router's settings, back the damned things up.

UPDATE: Newer versions of the FritzBox 7270/7390 firmware (for international models) have had the MAC spoofing capability restored (thanks to me pestering AVM and convincing them it was still necessary), as I explain in a newer post

1 comment:

  1. Hello there, and thanks for pushing them

    I'm trying to the same with one old 3270 model, but can't find the option anywhere... any hint of where it might be hidden or they just never made it available? talking about changing the default MAC

    many thanks!