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2704N continually muddling MAC addresses

r4
Hooked
Posts: 8
Thanks: 2
Registered: ‎03-03-2019

2704N continually muddling MAC addresses

Infuriating problem with this PN Thomson 2704N router belonging to my parents on their PlusNet connection (wasn't my choice of router, they somehow managed to burn out the perfectly good old Netgear one I'd supplied and then inform me out of the blue they'd obtained this freebie dog's dinner of a device instead).

 

I access their PC via SSH on a non-standard port number. On a previous visit, in their router settings, under Port Forwarding, I'd selected Secure Shell Server under the Game/Application list box, and accorded it to the correct MAC address of their PC. Going to 'Edit', I then changed the standard port 22 to the required number, and applied. This worked for months.

 

Then on my last visit, I wanted to make one simple change: the port number. Let's say I changed it from 7653 to 7626; it shouldn't make any difference. I updated this in the router settings. After returning abroad, I could no longer SSH to their PC. Following umpteen VOIP calls and screen sharing episodes, I've guided them through the procedure several times to fiddle with the router settings, but it always screws it up again shortly afterwards. In addition to their wired PC, which has a static IP address assigned (192.168.0.84), they also have an iPad connected over wifi with DHCP. The PC has a MAC beginning b8: whilst the iPad begins a6:

 

If I/they delete the existing entry on the router settings and create a fresh one, selecting the b8: MAC address, then update the port numbers, returning to the Port Forwarding screen it shows correctly under Device as Unknown-b8:xx:xx:xx:xx and then (b8:xx:xx:xx:xx) below in brackets. But if they navigate through some other tabs (Wifi, DNS, DynDNS, etc.) and come back to Port Forwarding, it then shows Unknown -b8:xx:xx:xx:xx with (a6:xx:xx:xx:xx) in brackets underneath. It is silently switching to the iPad MAC address every time. If I set it to the a6: MAC address, it stays like that forever, but select the b8: one and it gets overwritten some minutes or hours afterwards.

 

We've tried resetting the router to factory defaults and starting again. No luck. So why did it work perfectly okay for months before? Just to compound the misery, after getting them to correct it again this evening, I was in an SSH session but could no longer open any new sessions, so I knew it had switched again. I tried to open a text-based web browser from the console to access the router settings, but from the router configuration homepage (both the regular and 'expert user' versions) navigating to Advanced Settings stoutly refuses to co-operate because it has some cretinous scripting that doesn't work in text browsers, and you're forever stuck on the homepage.

Aside from burning this router in a ceremony and sending the ashes by post to PlusNet HQ, is there anything else worth trying?

1 REPLY 1
r4
Hooked
Posts: 8
Thanks: 2
Registered: ‎03-03-2019

Re: 2704N continually muddling MAC addresses

Update: I told my parents to leave the PC on overnight. Shortly before midnight, when they'll be snoozing, I tried connecting via SSH and it worked again. So I was able to have a look in the router configuration. The MAC address is back at b8:xx:xx:xx:xx but under the expert user settings I note the mention of DHCP lease time of 24 hours, under a default range up to 192.168.1.253, and there's a static route configuration underneath. Thinking this lease time could be causing the issue I've configured the static route. Remains to be seen if that will make any difference. But again, it was never necessary when it worked for months on end before.