TG585 internet indicator red but still passing traffic
About a week ago the Internet indicator light on my TG585 router switched from green to red, which I thought indicated no internet connectivity. However, the internet connection was plainly still working. I checked the router logs (nothing useful) and ran an internet connectivity check using the TG585 web interface. This reported everything fine up to the DSL layer but apparently failed to contact the gateway IP address, yet still the internet connection was live and usable. I rebooted the router and both behaviours persisted (Internet light red, connectivity check failed), but the internet connection was re-established and remains up.
I know Thomson routers have their quirks, but this one is almost 5 years old and has never exhibited either of these behaviours in the past - I've used the connectivity check before and it has always accurately represented the state of the link.
To investigate further I used a PC on my internal network to ping the gateway address that the router uses for its connectivity test and the gateway didn't respond. I also tried pinging the gateway from the router CLI, and received no response, which may explain why the connectivity check is failing. The same gateway address is still listed in the TG585's routing tables, though, so I guess it is still operational, but I'd like to know:
1. Has the configuration of the Plusnet gateways changed recently to block ICMP echo requests to their own addresses?
2. Has anyone else noticed similar behaviour on their routers recently? If this is an "upstream" issue I would expect more than just my account to be affected.
3. What does the Internet indicator being red actually signify? Could it be for the same reason that the connectivity check is failing, or is it a separate issue?
All thoughts on this gratefully received.
Re: TG585 internet indicator red but still passing traffic
The 'internet light red' situation has been seen before on both TG582 and TG585 https://community.plus.net/t5/forums/v3_1/forumtopicpage/board-id/Broadband/thread-id/174879/page/1 . I'm not sure that anyone ever got to the bottom of it. Interesting that yours doesn't appear to clear on a restart, from what I recall, in the past, a restart has sorted it.