Occassional dropouts

Peter_Stanley · 17-12-2005, 19:37

Okay, here's the problem. I'm on the 1Mbit service and 99.9% of the time all goes swimmingly (so much better than the ADSL line I just cancelled, but that's another story). However, every now and then strange dropouts occur when all internet requests go into a black hole. This can happen several times a day and lasts for anything from a few seconds to upwards of 5 minutes.

When the problem occurs, the ntl250 cable modem's POWER, SYNC and RDY lights remain solid. The ENET light remains solid except when data is being sent (e.g. I request a webpage), when both it and the SEND light flash briefly. However, the RECV light remain resolutely unlit.

During these periods, I can't ping any servers including NTL's DNS servers. Trying a tracert gives 30 reports of * * * Request timed out unless the connection recovers during the tracert, when it reports (for example):

1 * * * Request timed out.
2 * * * Request timed out.
.
.
.
30 16 ms 14 ms 13 ms cache1.ntli.net [194.168.4.100].

Power levels, especially upstream, jump around a bit, but I believe the steady SYNC and RDY lights mean my connection to the head end is okay, so what is the cause of this connectivity black hole?

I can still access the cable modem diagnostics during these dropouts, the problem occurs both with & without the router in the loop and on different pcs, so there is no connectivity issue on my LAN.

At the moment I can live with the minor inconvenience (chill pill taken, see below!) but does anyone else suffer the same symptoms or is this unique to me?

I don't relish the prospect of trying to explain this to NTL's Indian Support Centre, unless they've improved drastically in the last 9 months they don't understand intermittent. Seemingly the same problem (but more frequent/worse) was the reason I ditched NTL for ADSL early this year. That was an unhappy experience due to BT Wholesale and Aluminium phone cables

. So I'm back, tail between my legs with the same issue as before and would appreciate some guidance from the sages on here about likely causes and how to tackle this.

IanUK · 17-12-2005, 19:43

What are your power levels from the modem diagnostics ?

I had wildly fluctuating levels but a steady sync, it was traced to a fault.

cheers

Ian

Peter_Stanley · 17-12-2005, 20:04

Power levels when I checked them during a dropout:

2 Dec, Up: 38.0 dbmV, Down: 6.6 dbmV, Down SNR: 37.8
4 Dec, Up: 38.5 dbmV, Down: 6.2 dbmV, Down SNR: 37.5
16 Dec, Up: 52.5 dbmV, Down: 6.4 dbmV, Down SNR: 37.8
17 Dec, Up: 36.5 dbmV, Down: 6.5 dbmV, Down SNR: 37.6

Power levels when working okay:

2 Dec, Up: 38.0 dbmV, Down: 5.0 dbmV, Down SNR: 37.4
17 Dec, Up: 52.5 dbmV, Down: 6.5 dbmV, Down SNR: 37.2

There doesn't seem to be a correlation between dropouts and power levels.

IanUK · 17-12-2005, 20:08

Those up levels seem to have jumped a lot over the last few weeks, but I'm afraid I don't know if that would affect your service, hopefully Ignition or BBKing will see this thread and perhaps at least let you rule that in or out.

Peter_Stanley · 22-12-2005, 17:57

Just *bumping* the thread in the hope BBKing, Ignition, or anyone else who can help is passing by.

FWIW the connection seems to be acting up today - 4 dropouts since 16:00.

fragless · 23-12-2005, 12:48

Quote:

Originally Posted by Peter_Stanley

Okay, here's the problem. I'm on the 1Mbit service and 99.9% of the time all goes swimmingly (so much better than the ADSL line I just cancelled, but that's another story). However, every now and then strange dropouts occur when all internet requests go into a black hole. This can happen several times a day and lasts for anything from a few seconds to upwards of 5 minutes.

I also have the same problem, on 10mb and a 120 modem, had this since having 3mb BB when the 3mb started.

Sometimes it only happens a few times a day other times several times a day, and I also experience the same, no email, websites are dns works, and then it comes back to normal.

I have never reported it, and put it down to just 1 of those things

Also, I have changed my network card several times and tried 2 different routers but still the problem continues.

Moth · 26-12-2005, 18:04

I had a similar problem for a while - it cleared up after a week or two. I looked in my modem logs and saw that NTL was trying to upgrade my modem, but failed because the upgrade was the wrong image

051203142405 4-Error X501.35 Unit Update Failed.
051203142405 7-Information F502.1 Bridge Forwarding Enabled.
051203142404 4-Error X501.28 Unit Update - Not updating. This image is not for this platform.
051203142404 7-Information F502.2 Bridge Forwarding Disabled.
051203142404 7-Information X500.0 Attempting Unit Update

were the log messages I got.