Connection playing up in LU7 area for the past couple of weeks.

[Nilrem]

Hi

Our normally solid connection has been going down every couple of days for anything up to hour+ at a time for the the past couple of weeks or so (I think it started roughly the same time the STB's updated, although that's probably coincidence).

Sometimes it's just for about 15 minutes, sometimes it's for an hour+, rebooting the modem doesn't seem to help, however I have noticed that when it loses connection, the modem's event log tends to have a message about "DS channel override in cfg file, re-scanning downstream".

We're on 20mb, with a 250 modem.

The stats of the modem at the moment are
Downstream Lock : Locked
Downstream Channel Id : 30
Downstream Frequency : 307000000 Hz
Downstream Modulation : QAM256
Downstream Symbol Rate : 6952 Ksym/sec
Downstream Interleave Depth : taps12Increment17
Downstream Receive Power Level : 6.3 dBmV
Downstream SNR : 41.5 dB

Upstream Lock : Locked
Upstream Channel ID : 1
Upstream Frequency : 47400000 Hz
Upstream Modulation : QAM16
Upstream Symbol Rate : 2560 Ksym/sec
Upstream transmit Power Level : 41.3 dBmV
Upstream Mini-Slot Size : 2


Acquire a Downstream Channel 307000000 Hz Locked
Connectivity State OK Operational
Boot State OK Operational



And part of the event log from just before I rebooted it the other night (I had to reboot it again today as apparently it was down all morning, but forgot to copy the event log).

Mon Feb 15 00:42:53 2010 Mon Feb 15 00:42:53 2010 Information (7) DS channel override in cfg file, re-scanning downstream
Mon Feb 15 00:42:53 2010 Mon Feb 15 00:42:53 2010 Information (7) IP init completed ok
Mon Feb 15 00:42:53 2010 Mon Feb 15 00:42:53 2010 Information (7) CableModem TFTP init ok
Mon Feb 15 00:42:53 2010 Mon Feb 15 00:42:53 2010 Information (7) CableModem DHCP client init ok
Mon Feb 15 00:42:53 2010 Mon Feb 15 00:42:53 2010 Critical (3) DHCP WARNING - Non-critical field invalid in response.
Mon Feb 15 00:42:46 2010 Mon Feb 15 00:42:46 2010 Information (7) MAP w/initial maintenance region received
Mon Feb 15 00:42:46 2010 Mon Feb 15 00:42:46 2010 Critical (3) No Ranging Response received - T3 time-out
Mon Feb 15 00:42:46 2010 Mon Feb 15 00:42:46 2010 Information (7) MAP w/initial maintenance region received
Mon Feb 15 00:42:45 2010 Mon Feb 15 00:42:45 2010 Information (7) Downstream sync ok
Mon Feb 15 00:42:45 2010 Mon Feb 15 00:42:45 2010 Information (7) Beginning initial ranging...

Does anyone have any idea what's happening, and is it an engineer call or something else? (given that this seems to happen late night/early morning and fixes itself eventually I'm not sure an engineer coming out would see anything).

As I say, rebooting it doesn't necessarily seem to do anything, at least early on in it's loss of connection but does sometimes seem to help if I do it after a while?

[Sephiroth]

I reckon that you're on a CMTS that also serves the 50 meg tier. So far as I know that's how VM intend their architecture to be for now with the 10 meg tier on the legacy equipment.

The resets appear to accompany the DS Channel override events. I'm not sure why this would happen in the CMTS, but you may have been allocated a DS channel from the bonding group (used by 50 meg modems) in the initial sequence and the CMTS wishes to reallocate you to a non-bonding channel. The underlying reason would seem to me to be load balancing - but there are better brainios here who could possibly explain
this further.

Your modem stats are otherwise exemplary.

[Nilrem]

Cheers Sepiroth, that's about what i'd guessed, although why it's a problem I don't know (my BIL is just down the street with the same modem model and apparently isn't having issues).

I'll probably give them a ring tomorrow and see what they say