Some time ago I had issues with Draytek 2800 routers on adsl lines that were getting above 7 MB download speeds but that were having problems sustaining connection and found that a command had been added to the CLI which allowed setting the maximum download rate to a value that was less but more reliable. So I used that on a number of occasions and specifically found it to stabilise the connection.
Recently then when testing a 2820 – I found what looked to be a similar problem. The connection moved from a 7.5m to 8M download speed after a 2800 was removed and replaced with a 2820 – thats when the problem started. Hosts served out from behind the router started to become unavailable. Thats when I found that the rate capping command had been removed from the 2820 since its a different chipset to the 2800s.
I currently have a call open with Vigor to get to the bottom of this and I’ll write further when they respond – the suggestion is a firmware bug.
Meanwhile the 2800 with wireless issues is back in play and the 2820 is being a very expensive network access point.