Cannot try it on mine at present however under <BASIC>; <WAN>; there is a WAN connection enable. Wondering if that would force a re-sync?
I thought you had it there, but try it at your own risk!
I un-ticked WAN connection Enable and submitted it. After a few seconds the page refreshed with it un-ticked and the Enable marker at the top right = 0.
Went and looked at the HG612, DSL light still on. My earlier telnet method turned it off.
Then I came back down here to turn the WAN Enable back on and when I tried to access the modem got the TG582N login page! Hmmm thinks me! But I couldn't log into that over wifi.
Went to look, and the "Internet" light on it was red. Tried the wired machine, again not able to log into the router. Everything dead as far as I was concerned, all lights on the modem green, router OK except for this red light, both computers thinking they had internet access. Which they hadn't - both just giving the router login page but not able to log in.
Took the modem power plug out, waited a bit, plugged it back in. Came up looking OK but the router stayed Red for internet. Perhaps then I didn't wait long enough for the PPP session to come up. I'm not going to try again, so I shan't know if the power cycle on the modem had re-enabled the WAN connection. I think it unlikely.
Did a factory reset on the modem, knowing that should re-enable WAN. Once that came back up I still had to wait a long time for PPP to come up, hence my comment in the previous paragraph, but all is well.
A very strange result from un-ticking that box.
The indispensable man or woman passes from the scene, and what happens next is more or less the same thing as was happening before.
My broadband basic info/help site - www.robertos.me.uk.
Domains, site and mail hosting - Tsohost
Connection - Plusnet
UnLim Fibre (FTTC). Sync 58162/14182kbps @ 600m. - BQM