User comments on ISPs
  >> Madasafish


Register (or login) on our website and you will not see this ad.


  Print Thread
Standard User rnewfie
(member) Fri 22-Apr-11 12:00:53
Print Post

What is all this?!


[link to this post]
 
My line is quite stable, but I do have to boot my router with DMT running to force an SNRM of 4.0 so as to get a sync speed of over 3424, which puts me on a 3000 profile.
After syncing at > 3424, my line stays stable for several days and sometimes weeks until the following happens.
It is always in the early hours of the morning and means that I lose my 3000 profile and have to re-boot my router with DMT, etc.
So what causes the following? No-one is using the router at this time of day :-
Apr 16 01:31:12 user crit kernel: ADSL link down
Apr 16 01:31:13 daemon crit pppd[730]: Clear IP addresses. Connection DOWN.
Apr 16 01:31:13 daemon crit pppd[730]: Clear IP addresses. PPP connection DOWN.
Apr 16 01:31:23 user crit kernel: ADSL G.994 training
Apr 16 01:31:28 user crit kernel: ADSL G.992 started
Apr 16 01:31:31 user crit kernel: ADSL G.992 channel analysis
Apr 16 01:31:35 user crit kernel: ADSL G.992 message exchange
Apr 16 01:31:36 user crit kernel: ADSL link up, interleaved, us=288, ds=3104
Apr 16 01:31:43 daemon crit pppd[730]: PPP LCP UP.
Apr 16 01:31:43 daemon crit pppd[730]: PPP LCP UP.
Apr 16 01:31:44 daemon crit pppd[730]: Received valid IP address from server. Connection UP.
Apr 16 03:38:58 user crit kernel: ADSL link down
Apr 16 03:39:00 daemon crit pppd[730]: Clear IP addresses. Connection DOWN.
Apr 16 03:39:00 daemon crit pppd[730]: Clear IP addresses. PPP connection DOWN.
Apr 16 03:39:13 user crit kernel: ADSL G.994 training
Apr 16 03:39:18 user crit kernel: ADSL G.992 started
Apr 16 03:39:21 user crit kernel: ADSL G.992 channel analysis
Apr 16 03:39:25 user crit kernel: ADSL G.992 message exchange
Apr 16 03:39:26 user crit kernel: ADSL link up, interleaved, us=448, ds=3200
Apr 16 03:39:32 daemon crit pppd[730]: PPP LCP UP.
Apr 16 03:39:32 daemon crit pppd[730]: PPP LCP UP.
Apr 16 03:39:33 daemon crit pppd[730]: Received valid IP address from server. Connection UP.
Apr 16 04:06:04 user crit kernel: ADSL link down
Apr 16 04:06:06 daemon crit pppd[730]: Clear IP addresses. Connection DOWN.
Apr 16 04:06:06 daemon crit pppd[730]: Clear IP addresses. PPP connection DOWN.
Apr 16 04:06:10 user crit kernel: ADSL G.994 training
Apr 16 04:06:15 user crit kernel: ADSL G.992 started
Apr 16 04:06:18 user crit kernel: ADSL G.992 channel analysis
Apr 16 04:06:22 user crit kernel: ADSL G.992 message exchange
Apr 16 04:06:23 user crit kernel: ADSL link up, interleaved, us=128, ds=2976
Apr 16 04:06:30 daemon crit pppd[730]: PPP LCP UP.
Apr 16 04:06:31 daemon crit pppd[730]: PPP LCP UP.
Apr 16 04:06:31 daemon crit pppd[730]: Received valid IP address from server. Connection UP.
Apr 16 06:13:11 user crit kernel: ADSL link down
Apr 16 06:13:12 daemon crit pppd[730]: Clear IP addresses. Connection DOWN.
Apr 16 06:13:12 daemon crit pppd[730]: Clear IP addresses. PPP connection DOWN.
Apr 16 06:13:22 user crit kernel: ADSL G.994 training
Apr 16 06:13:28 user crit kernel: ADSL G.992 started
Apr 16 06:13:30 user crit kernel: ADSL G.992 channel analysis
Apr 16 06:13:34 user crit kernel: ADSL link up, interleaved, us=160, ds=3168
Apr 16 06:13:40 daemon crit pppd[730]: PPP LCP UP.
Apr 16 06:13:41 daemon crit pppd[730]: PPP LCP UP.
Apr 16 06:13:41 daemon crit pppd[730]: Received valid IP address from server. Connection UP.
Apr 16 06:28:11 user crit kernel: ADSL link down
Apr 16 06:28:12 daemon crit pppd[730]: Clear IP addresses. Connection DOWN.
Apr 16 06:28:12 daemon crit pppd[730]: Clear IP addresses. PPP connection DOWN.
Apr 16 06:28:18 user crit kernel: ADSL G.994 training
Apr 16 06:28:23 user crit kernel: ADSL G.992 started
Apr 16 06:28:26 user crit kernel: ADSL G.992 channel analysis
Apr 16 06:28:30 user crit kernel: ADSL G.992 message exchange
Apr 16 06:28:30 user crit kernel: ADSL link up, interleaved, us=416, ds=3456
Apr 16 06:28:37 daemon crit pppd[730]: PPP LCP UP.
Apr 16 06:28:37 daemon crit pppd[730]: PPP LCP UP.
Apr 16 06:28:38 daemon crit pppd[730]: Received valid IP address from server. Connection UP.
Apr 16 06:33:02 user crit kernel: ADSL link down
Apr 16 06:33:04 daemon crit pppd[730]: Clear IP addresses. Connection DOWN.
Apr 16 06:33:04 daemon crit pppd[730]: Clear IP addresses. PPP connection DOWN.
Apr 16 06:33:13 user crit kernel: ADSL G.994 training
Apr 16 06:33:18 user crit kernel: ADSL G.992 started
Apr 16 06:33:21 user crit kernel: ADSL G.992 channel analysis
Apr 16 06:33:25 user crit kernel: ADSL G.992 message exchange
Apr 16 06:33:25 user crit kernel: ADSL link up, interleaved, us=160, ds=3168
Apr 16 06:33:31 daemon crit pppd[730]: PPP LCP UP.
Apr 16 06:33:32 daemon crit pppd[730]: PPP LCP UP.
Apr 16 06:33:32 daemon crit pppd[730]: Received valid IP address from server. Connection UP.
Standard User rnewfie
(member) Tue 26-Apr-11 09:48:59
Print Post

Re: What is all this?!


[re: rnewfie] [link to this post]
 
No response from anyone after 4 days!

I seem to have asked a question which no-one can answer wink

Surely some clever soul knows what causes this - ISP peeps - Hello, is anybody there?!
Standard User GeeTee
(member) Tue 26-Apr-11 12:24:06
Print Post

Re: What is all this?!


[re: rnewfie] [link to this post]
 
All the logs show is that the line loses synch several times over a number of hours.

Could be any number of things causing it.
e.g.
Noise being introduced on the line between you and the exchange.
Maintenance work at the exchange.

Does the line run past any light industrial areas?

Do you have any means of monitoring the SNRM?

Edited by GeeTee (Tue 26-Apr-11 12:26:34)


Register (or login) on our website and you will not see this ad.

Standard User rnewfie
(member) Tue 26-Apr-11 13:22:48
Print Post

Re: What is all this?!


[re: GeeTee] [link to this post]
 
As I said before, 'It is always in the early hours of the morning'. Actually, to be more specific, it is ONLY in the early hours of the morning.

I have monitored SNRM and the latest log from a few days ago shows a max SNRM of 6.8 and a min of 5.3, but this is when there have been no dropouts. The max no. of CRCs per minute was 10 and that was only for one minute.
Whenever I run the monitor, the line has no problems - example of Murphy's Law.

'Noise being introduced on the line between you and the exchange.' - Possibly, but why is it only ever between 1am and 7am?

'Maintenance work at the exchange.' - Possibly. Do BT work overnight at exchanges?

'Does the line run past any light industrial areas?' - Possibly, but only in the early hours of the morning wink

My guess is maintenance work, but after 1 am?

This only occurs about once per month at a guess, but of course it causes re-syncs, which knocks my profile down a notch or two for several days due to BT's silly profiling system.

PS - what causes the upstream sync to vary such a lot when this is happening? It starts off at 448 and goes as low as 128.

Edited by rnewfie (Tue 26-Apr-11 13:26:41)

Standard User GeeTee
(member) Tue 26-Apr-11 13:58:47
Print Post

Re: What is all this?!


[re: rnewfie] [link to this post]
 
Yep, Murphy's Law always seems to come into play with intermittent problems like this smile

'Noise being introduced on the line between you and the exchange.' - Possibly, but why is it only ever between 1am and 7am?
Maybe a business running up a backup generator to test it or maintenance work at exchange.

'Maintenance work at the exchange.' - Possibly. Do BT work overnight at exchanges?
Yes. Any service affecting maintenance is done overnight / out of hours when possible.

'Does the line run past any light industrial areas?' - Possibly, but only in the early hours of the morning

My guess is maintenance work, but after 1 am?
Telcos / ISPs / CPs etc. all tend to do service affecting maintenance work in the wee small hours.

PS - what causes the upstream sync to vary such a lot when this is happening? It starts off at 448 and goes as low as 128.
This is where the SNRM / attenuation / error logs would be handy. If it's bursts of noise that are taking the connection out and the DSL re-synchs whilst the noise is still present, this could very well cause the connection speed to be lower.
  Print Thread

Jump to