cancel
Showing results for 
Search instead for 
Did you mean: 

Power Off & DLM

Kremmen
Rising Star
Posts: 501
Thanks: 5
Fixes: 1
Registered: 13-04-2013

Power Off & DLM

Next week I'm wallpapering and I'm going to have to turn the lecky off for a short period to get behind the wall socket that the modem is powered by.
Does the leaving it off for half hour minimum still apply to avoiding DLM issues?
Ta
Let's be careful out there !
104 REPLIES
sjptd
Grafter
Posts: 486
Thanks: 4
Registered: 01-09-2014

Re: Power Off & DLM

I suspect nobody knows for sure, except maybe the people who wrote the DLM code.  I doubt a single power off and power on with a few minutes break will do much harm, but ...Huh  It seems to be agreed that the really bad thing is disconnecting the phone line without first powering off.
Plusnet Help Team
Plusnet Help Team
Posts: 5,614
Thanks: 530
Fixes: 203
Registered: 01-01-2012

Re: Power Off & DLM

Generally speaking one power off shouldn't cause a issue.
If it was being turned on and off repeatedly that may trigger something.
If this post resolved your issue please click the 'This fixed my problem' button
 Matthew Wheeler
 Plusnet Help Team
danludlow
Rising Star
Posts: 395
Thanks: 24
Fixes: 1
Registered: 03-12-2014

Re: Power Off & DLM

Out here in the countryside we all too frequently suffer power cuts. Usually in high wind, often combined with rain and trees touch cables. We get a cut, then a blip when breakers try to trip back in automatically, we also get thunderstorms, and I suspect interference. maintenance power cuts seem frequent too. My point, is that I'd be very surprised if DLM copes with some of cuts and doesn't respond. I feel that BTO's DLM is probably not best designed for rural areas, and I've long felt that it reacts far too quickly, which wouldn't matter if it restored even half as quickly, but my experience (if DLM is what I seem to suffer) suggests that it locks down and then stays put.
Cruising through our nearby town (also well served by Virgin Media)  recently, I was almost stunned by the number of FTTC Cabinets. In one road alone, more than in our entire village, and all within my distance to my cabinet. In town, more than 200 metres seemed unlikely, out here, I'm 800 metres away, and I'm not the furthest out, by a distance. We are extremely lucky to have VDSL2 broadband out here, so I can't complain, and BTO have to supply expensive equipment and try to make a profit. The cabinets can't be cheap and so longer runs help the economics I suspect.
That said, I hope that BTO are actively looking at means to improve the rural distribution in areas where they have no other competition.
Kremmen
Rising Star
Posts: 501
Thanks: 5
Fixes: 1
Registered: 13-04-2013

Re: Power Off & DLM

Thanks
I'm not expecting any issues when I turn the mains back on but thought I'd better check. I'm just going to flick the main box switch off and on when done, like a power cut.
Just checked with a roll and the join drops right through the socket centre so it will definately be over half an hour at the speed I get sheets up. I'm not clever enough to cut round the socket plus I need to shift the old paper from behind it anyway. Far neater I think  Smiley
Let's be careful out there !
Kremmen
Rising Star
Posts: 501
Thanks: 5
Fixes: 1
Registered: 13-04-2013

Re: Power Off & DLM

All done.
Hopefully from about lunchtime Sunday when power was restored my connection is rock solid again.
Let's be careful out there !
Community Veteran
Posts: 19,101
Thanks: 443
Fixes: 21
Registered: 31-08-2007

Re: Power Off & DLM

Just for the record, the empirical evidence that came from Fibre trials suggested that a minimum time off of one hour was generally a better bet, and as remarked earlier - drop the PPP session first (login to the Router and click Disconnect) then power-off the Router before the Modem, where they are separate units.
Community Veteran
Posts: 6,824
Thanks: 1
Registered: 27-10-2012

Re: Power Off & DLM

That contradicts the advice given from OR and the recent changes they made to the DLM for MTBR.
alext05
Grafter
Posts: 162
Registered: 16-12-2013

Re: Power Off & DLM

What is the OR advice?
Community Veteran
Posts: 19,101
Thanks: 443
Fixes: 21
Registered: 31-08-2007

Re: Power Off & DLM

I don't care what advice it contradicts Andy and why don't you quote it instead of posting in such a "know it all manner". My advice always errs on the precautionary side and as users with locked modems won't necessarily be aware of other issues on their line, a longer time off is generally a safer bet. Note my words
Quote from: Anotherone
......a minimum time off of one hour was generally a better bet
Community Veteran
Posts: 6,824
Thanks: 1
Registered: 27-10-2012

Re: Power Off & DLM

Surely you should care if the advice OR give is different to what you're saying?
I've quoted the information before and the recent changes. This came directly from OR presentations to ISPs.
I am not sure which empirical evidence you're referring to because the original FTTC trials were some 5 years ago and used a different DLM parameters.
sjptd
Grafter
Posts: 486
Thanks: 4
Registered: 01-09-2014

Re: Power Off & DLM

Quote
That contradicts the advice given from OR and the recent changes they made to the DLM for MTBR.

You may have a point: as you suggest: we should care if the advice OR give is different to what you're saying.
However, remember that your posts are seen only in the context of the thread.
As well as not knowing what the contradicted OR advice was, I still don't know which of the previous posts you are claiming contradicts that advice.
A little more care in posting could make the posts much more useful.
Community Veteran
Posts: 19,101
Thanks: 443
Fixes: 21
Registered: 31-08-2007

Re: Power Off & DLM

@AndyH
Especially as alex05 had asked, and now sjptd, but as you haven't
1) quoted whatever advice they were giving and even tried to back it up with documentary evidence
2) quoted any other information that would demonstrate that DLM doesn't take other factors into account besides the MTBR before acting -
then I can only conclude that you are in no position to criticise my precautionary advice.
Are you intimately familiar with the algoriths used by the Fibre DLM - no you aren't because BT don't make all the information public - and neither am I before youi try and twist what I've said, that is why the advice is always Precautionary.
alext05
Grafter
Posts: 162
Registered: 16-12-2013

Re: Power Off & DLM

@Andy H
We would care about the advice OR has given if we knew what it is. I am, for one, interested, but you seem to be unable to bring yourself to quote OR or to link to the original source (or your previous quote). How cool is that!
Here is the quote from Plusnet rep on this thread:
Quote from: Matthew
Generally speaking one power off shouldn't cause a issue.
If it was being turned on and off repeatedly that may trigger something.

Is that the OR advice or Plusnet don't know it either?
Andrue
Pro
Posts: 775
Thanks: 90
Fixes: 1
Registered: 12-01-2015

Re: Power Off & DLM

This might help clarify why powering off the BTor supplied modems is fairly safe:
http://forum.kitz.co.uk/index.php?topic=12582.msg237823#msg237823
Other makes of modem may behave differently.