VM 256 modem software download fail

[Rob M]

Given that we're running 1 hour ahead of GMT at the moment (British Summer Time = GMT +1) if your watch was showing 09:28:36 then it would actually have been 08:28:36 GMT so I suspect that the logs are actually just showing GMT with no allowance being made for BST.

I could be wrong though

[Sambora]

Originally Posted by ceedee

Because _something_ is causing your cable modem to reboot (several times a day), which takes you offline momentarily and the UBR attempts to update the firmware.

Try thinking of it as the _something_ as the "egg" and the 'failed' update is the "chicken"!

Very good analogy!

Originally Posted by GrahamP

Hi everyone

An update on this from my side.

Had an engineer out yesterday. He had absolutely no clue about CMTS and DOCSIS upgrades and why these would be making my modem restart.

As you have described below, it looks like you have an underlying physical connectivity problem that is making your modem restart.

When your modem restarts it checks the firmware level. Just to be clear it isn't CMTS that is trying to upgrade your modem - see the "chicken and egg" explanation from ceedee

Originally Posted by GrahamP

FYI. UNICAST Maintenance does = connection loss (albeit momentarily)

His solution, root around out front, reset the connection to the house, replace the modem.

I really didn't think it would work as it didn't seem to be getting to the root for the problem.

However! As oppossed to the 50/100/ or 200+ attempted updates I was getting before, I've only had under 10 in the last 24 hours = far better connection. (Hoping its not just coincedence!)

Did he also check power levels? It might be worth posting them (probably in a seperate thread).

Interesting Article if you like this kind of thing http://www.cisco.com/en/US/tech/tk86...80094bb1.shtml

[ceedee]

Originally Posted by GrahamP

FYI. UNICAST Maintenance does = connection loss (albeit momentarily)

Extending that logic, it would suggest that an engineer managed to decrease the frequency of your UBR's attempts to update your modem by rooting around the front of your house and replacing the modem.
Which I hope you'll accept is pretty unlikely!

We know that:

reboot = connection loss (albeit momentarily) = UNICAST Maintenance (attempt to update firmware)

so applying Occam's Razor, _something_ is causing your modem to reboot and the frequency has been reduced by the engineer.

ymmv

---------- Post added at 10:51 ---------- Previous post was at 10:44 ----------

Originally Posted by Sambora

Very good analogy!

Thank you.
I frequently find that identifying faults is easier if you look at the symptoms upside down!


Hope it's useful to the posters with problems...

[GrahamP]

Hi All

Interesting. I think i'm beginning to understand now. So the UNICAST maintenance is occuring after my modem restarts which is caused by another unrelated issue which is why this message always appears when my connection drops?

It isn't the CMTS trying to update my modem? Rather, it's my reset modem asking the CMTS if there is anything available for it...

Interesting about the power level issues. I was under the impression that anything between -15 and +15 is fine. In fact, I've run the modem at about 7 different power levels ranging from +14 to +0.4 which I have currently. The most stable so far has been the +0.4 but I'm not entirely sure it's related.

Only 4 connection drops so far today, although 3 of those within the last 3 hours. Usually I would have been up to over 30 by now.

I've heard a few people mention old cable splitters (tv/bb) being an issue, but I've tried the connection straight through to the modem and its the same issue.

[Sambora]

Originally Posted by GrahamP

Interesting about the power level issues. I was under the impression that anything between -15 and +15 is fine. In fact, I've run the modem at about 7 different power levels ranging from +14 to +0.4 which I have currently. The most stable so far has been the +0.4 but I'm not entirely sure it's related.

I assume that you are referring to downstream power levels but I suspect that you either have an upstream power issue or a Signal to Noise problem.

The preferred levels do vary slightly by QAM setting. There is a good article on this at http://tinyurl.com/6dzqr I'll take a guess that your upstream power level is 56 or higher.

However your downstream should be more stable than that, what timescale are the 7 levels taken at?