Draytek 2820 Routers and SIP Handsets

This is a quick post for anyone who is having Draytek Vigor Routers + SIP problems. It’s taken me weeks to get to the bottom of these issues, so hopefully it’ll save others the time. It’s worth mentioning that I have only had issues and tested routers with the UK firmware and have no idea if these issues exist in other version.

Symptoms: Registrations from SIP handsets behind 2820 routers in NAT mode randomly becoming unavailable and refuse to re-register. This exhibits itself on the SNOM 300 handsets that we predominantly use with the dreaded ‘Network Failure’ message.


i) Check the firmware version on your router. (the lastest at the time of writing) seems to have some serious issues with SIP handsets. I have reverted back to 3.3.3_232201 which seems stable so far (fingers crossed)

ii) Make sure ‘Accept large incoming fragmented UDP or ICMP packets’ is disabled. This can be done in the web interface under: Firewall=>General Setup by unticking the checkbox

iii) Disable SIP_ALG. You’ll have to telnet into your router to do this. Once logged in you will have to issue the commands:

1. > sys sip_alg 0 — Disables sip alg

2. > sys commit — Apply changes

3. > sys reboot — Reboot router

I hope this is of use to someone.

March Post

haven’t posted in a while. though I’d write a quick note on a few things that heave really impressed me in the last couple of months

i) my ipod touch (thanks tom). it is now an indispensable device to me. a few useful tips – (a) jailbreak it as there are loads of neat application for it (I am now running jailbroken 1.1.3 with wobbly icons) (b) videora is pretty good for converting video files to itunes format (c) the back is easily scratched, the front is not

ii) ruby on rails – I know I’m probably years late in realising this, but it is actually *magic*

iii) the new series of torchwood is *really* good

iv) pitch black and the chronicles of riddick are pretty watchable films. I can’t quite put my finger on why I enjoyed them so much, but I did !

v) listen to seasick steve, he’s great

Freelander Repair Diary Pt. II

Well, the Freelander went through it’s MOT fine (hurrah !) and it’s now taxed and on the road. Now I need to start the repairs. I’m going to start on the electric windows. The one in the tailgate has serious potential to be broken if it’s not fixed soon. I notice my Haynes manual has very little information on how to fix electric windows. Doh!

Freelander Repair Diary

So, my sister and her husband gave me their Landrover Freelander mainly because of it’s unreliability and them figuring that I would be able to provide enough running maintenance to keep it going. The initial problem was that although it was a UK spec car it was in fact on Belgium plates so I’ve had to wait 4 weeks for DVLA to cough up a new V5. Anyway it’s here now and tomorrow it’s going in for an MOT.

I’ve just spent an hour pulling the rear tailgate apart to try and track down the “window doesn’t drop when tailgate opens” problem. The Freelander has an electric window in the tailgate which is a nice feature. The window doesn’t have a surround to it, it’s just a sheet of glass standing proud of the actual door. To prevent it fouling on the various pieces of plastic trim around the roof line the tailgate has this feature that the glass drops about half an inch on opening and then returning to closed when shut. It doesn’t actually do this, threatening to snap the sheet of glass off if you attempt to access the boot without first opening the window manually. The electric window works fine under normal condition so it didn’t seem to be a problem with the window itself so I guessed that the problem lay with the lock mechanism which must have a switch in it to signal the cars computer to lower the rear window.

Thanks to eBay I bought a cheap replacement lock mechanism and fitted it – to no avail. Examining the problem a bit closer it appears that the windows does seem to be trying to drop on opening just to succeeding. In fact you can push it down the half an inch by hand so it appears that the problem probably lies with the mechanics of the electric window mechanism after all. I also refitted the original UK plates (hurrah).

Things I know need doing off the top of my head:

– Pretty much all the windows (electric) and sunroof (electric) need dismantling and servicing
– I need to fit some kind of coolant header tank water level warning sensor to try and give me an early warning of any head gasket shenanigans.
– The brakes need stripping down and pads/shoes replacing.
– I think that the IRD bracket may be cracked ( http://www.myfreelander.com/transprobs4.htm )
– I think that the rear diff bearings may be worn ( http://www.myfreelander.com/fdprobs4.htm )
– The gaiter around the front of the prop shaft shredded itself driving back from Belgium
– Check the Viscous Coupling to prevent prop shaft snapping hilarity

If you want as many good reasons as you can think of not to buy a Freelander read this:


(I should point out that this Freelander is a 1998 one and currently on it’s 3rd engine)


I’ve accumulated a big pile cds/dvds from the front of the various games magasines I’ve been reading in my sick bed during the week. although I still have a pretty heavy cold I’ve managed to make it as far as my study to stick a few of them in my computer.

dvd from the front of pc zone:

halo: combat evolved

I’ve already finished this game on the x-box and it is very cool. although on the pc the graphics are more detailed and it’s a relief to be able to play with a mouse rather than a controller it somehow doesn’t quite seem right – despite turning all the video setting to maximum I all the textures just seem a bit blurry from a distance. maybe it’s a sign I should get a new graphics card.

pro evolution soccer 3

couldn’t even bring myself to bother installing it.


I was almost imediately annoyed by my sidekick – sister celeste – who seemed to exercise no caution at all when going into battle. she’d disappear into the distance, sword waving and be fairly knackered by the time I got there. what is more stupid is that she would then fail to pick up any of the plentiful health packs lying around to heal herself. the in game graphics are quite pretty but I think enough wars have been fought over religion, I’d prefer to fight about something more realistic . . . like alien invasion !

chicago 1930

this game appears to bascially be syndicate the only differences being it’s set in 1930 and its crap.

silent hill 3
wouldn’t run as it apparently needs a video card with programmable vertex/pixel shader support. I really really need a new graphics card !


this was an online demo and I really couldn’t be bothered to find a server and play online so all I could do was start my own server and wander round like billy no-mates looking at the pictures on the walls. the game is a cell shaded fps and looks pretty good. I can’t really say any more than that due to the total lack of anything to go on. I would however be nice if stuff like sheets of glass, computers, plant pots, etc. broke when you shot them.

fifa 2004

ffffttt – football again. no thanks.

. . . . . . . . .

time passes

. . . . . . . . .

ok – so I got distracted for about 8 hours and went and bought hitman 2 for the x-box so I’ve been playing that instead – I’ll let you know how it goes.

but for now – bed.

the flu

well, it’s been quite a while since I wrote a diary entry – 17 months to be exact (how lazy is that). quite a lot’s happened in that time, the main things being getting married to janie and becoming a father to be. all in all it’s been quite an exciting year – although the culmination (the birth) doesn’t happen till january.

I’ve been in bed ill since tuesday night with the flu. I’m feeling a little better now so decided to put my spare time to good use and actually write an entry.

I bought max payne last weekend for my x-box. although it’s quite an old game now I was pretty impressed – a really good story line and a really “dark” feel to it. “bullet time” is really neat too ! needless to say I finished it after a couple of days – but thats ok, max payne 2 is out now so the only decision I have to make is wether to buy it for my pc or x-box.

I feel quite pleased that the article I wrote about installing debian with an adaptec hostraid controller has so far led two other people to contact me. when I wrote the article I guess I didn’t really think that anyone would read it – I guess I have google to thank for that.

steve cole is on holiday in florida at the moment leaving roland and I (infact mainly roland as I’ve been off work sick) to cope with the dizzy world of technical support on our own. before he went he manged to install moveable type so you can keep up with his holiday antics online.

tom and I have been gradually watching seasons of babylon 5 and farscape. I’ve been a long time fan of babylon 5 but have never actually watched *all* the episodes in order – we’ve just finished season 3 but unfortunately season 4 isn’t due out untill january – bit of a wait !. I only watched farscape for the first time this year, I have to admit I’m hooked – it’s great – not really like any other scifi show I’ve seen. I was quite pleased to be rated as a “manic academic farscape fanatic” on the farscape purity test at http://www.sadgeezer.com/.

well – it looks like janie may well be coming down with my flu, so I guess I better look after her and start cooking tea.