For the last few weeks, I have been experiencing regular connection dropouts (a least 2-3 per day) on my BT FTTC connection and Draytek 2860 router running the 3.8.9.4 BT firmware. Prior to this, my connection was very solid and would go weeks (if not months) at a time without any issues whatsoever (and was quite fast - 75 downstream & 20 upstream). The SnR hovered around 5-6 for both downstream and upstream (which again, seemed to be more than good enough for the router to maintain a stable connection).
When things started to go wrong, I assumed (as one does) that the issue was line related (e.g. yet another incompetent Openreach engineer screwed something up at the panel, the recent spate of wet weather was causing noise on the line, etc). However, from what I could tell, the SnR hadn't decreased and in fact, was increasing due to the regular dropouts causing the DLAM to lower the connection speed. The only statistic that seemed to stand out was the number of LOS Failures was quite high (around 10 at one point)
Eventually after a further week of dropouts (my connection was down to 59/15 by this point) I decided that the issue was less likely to be line-related (the SnR was at 10 and 7 at this point) and more likely to be router related. The reasoning behind this was because the dropout problems seemed to begin around the time I had accidentally made (and then immediately reverted back) a minor configuration change to the router, but had chosen at the time to ignore the forced "restart your router" prompt which so annoyingly pops up after even the most minor of config changes on Draytek routers. I also noticed that the dropouts seemed to happen when the router was under a higher load (i.e. 2 people watching Iplayer and Netflix)
Since the problems started I have restarted/physically powered off the router multiple times, but this has had no effect on the dropouts.
As an experiment, I decided to see what would happen if I restored a backed up version of the configuration from the week prior to when the dropouts started (I have my config auto backing up to a USB stick). The decision to try this was in part driven by the fact that I noticed that the byte count on the config file was different between the current version and the backup, but in theory should have been the same as I had reverted back the accidental config change.
Sure enough, 72 hours later, I haven't had a single drop out, the LOS Failure count is 0, and the SnR is 9 down / 6 up at the moment.
This isn't the first time that something like this has happened (years ago I had a similar problem and I fixed it in the end by completely rebuilding and reconfiguring my router from scratch).
I am 99% certain it has something to do with the configuration getting "corrupted" due to my making a change to the configuration and then reverting it back without doing the "mandatory" router restart when prompted.
Anyway, if any of you Draytek owners out there experience a similar issue with inexplicable dropouts despite having good line stats, this is definitely something to consider (and do let me know as it would be good to hear that I am not the only one to experience this issue).
Cheers,
mbanqua
