Random disconnections from a Terayon TJ715x cable modem?

What about the diagnostic log webpage at that time ? (-l option) and check for things happening around that time.

I will have to wait for the next disconnection. I have had checked the logs after the disconnections before. I didn't see anything odd. Here's an example from hours ago:

Date (Y/M/D) Time Event ID Counter Level Event Text

2008/08/16 18:06:45 85000200 1 Critical UCD invalid or channel unusable

- T1 timeout: Giving up on UCD 41.

2008/08/16 18:08:47 82000400 1 Critical Received Response to Broadcast Maintenance Request, But no Unicast Maintenance 1970/01/01 00:49:45 82000200 1 Critical No Ranging Response received - T3 time-out. 2008/08/18 14:37:06 84000500 1 Critical SYNC Timing Synchronization failure - Loss of Sync 2008/08/18 14:37:26 82000400 1 Critical Received Response to Broadcast Maintenance Request, But no Unicast Maintenance 2008/08/18 15:20:18 82000200 4 Critical No Ranging Response received - T3 time-out. 2008/08/23 23:00:29 84000500 3 Critical SYNC Timing Synchronization failure - Loss of Sync 2008/08/23 23:00:47 82000400 1 Critical Received Response to Broadcast Maintenance Request, But no Unicast Maintenance 2008/08/23 23:10:04 84000500 2 Critical SYNC Timing Synchronization failure - Loss of Sync 2008/08/23 23:10:30 82000400 1 Critical Received Response to Broadcast Maintenance Request, But no Unicast Maintenance 2008/08/27 07:45:23 84000500 1 Critical SYNC Timing Synchronization failure - Loss of Sync 2008/08/27 07:45:54 82000400 1 Critical Received Response to Broadcast Maintenance Request, But no Unicast Maintenance 2008/08/27 07:48:23 82000200 16 Critical No Ranging Response received - T3 time-out. 2008/08/27 07:48:23 82000300 1 Critical Ranging Request Retries exhausted 2008/08/27 07:48:23 85000200 1 Critical UCD invalid or channel unusable

- T3 timeout: Giving up on UCD 10.

2008/08/27 07:49:37 82000200 16 Critical No Ranging Response received - T3 time-out. 2008/08/27 07:49:37 82000300 1 Critical Ranging Request Retries exhausted 2008/08/27 07:49:37 85000200 1 Critical UCD invalid or channel unusable

- T3 timeout: Giving up on UCD 8.

2008/08/27 07:51:05 82000200 16 Critical No Ranging Response received - T3 time-out. 2008/08/27 07:51:05 82000300 1 Critical Ranging Request Retries exhausted 2008/08/27 07:51:05 85000200 1 Critical UCD invalid or channel unusable

- T3 timeout: Giving up on UCD 9.

2008/08/27 07:52:12 82000200 12 Critical No Ranging Response received - T3 time-out. 2008/09/01 02:18:00 84000500 1 Critical SYNC Timing Synchronization failure - Loss of Sync 2008/09/01 02:18:13 82000400 1 Critical Received Response to Broadcast Maintenance Request, But no Unicast Maintenance 2008/09/01 02:21:38 84000500 4 Critical SYNC Timing Synchronization failure - Loss of Sync 2008/09/01 02:21:39 82000400 1 Critical Received Response to Broadcast Maintenance Request, But no Unicast Maintenance 2008/09/01 02:21:49 84000500 1 Critical SYNC Timing Synchronization failure - Loss of Sync 1970/01/01 00:00:03 2242905932 1 Notice SNMP Poll - Eth Link Up. 1970/01/01 00:00:08 68000300 1 Warning DHCP WARNING - Non-critical field invalid in response 2008/10/02 13:27:23 66010100 2 Error Missing BP Configuration Setting TLV Type: 17.9 2008/10/02 13:27:25 2242905917 1 Notice SNMP Poll - Mac Link Up. 2008/10/02 13:27:25 2242905786 1 Notice SNMP Poll - DS Link Up. 2008/10/02 13:27:25 2242905803 1 Notice SNMP Poll - US Link Up. 2008/10/02 13:27:25 2242905723 1 Notice SNMP_AGENT_COLD_START

Note that 10/2/2008 what the cable modem reboot I did earlier. ;) I will check again for the next one(s).

On 10/02/2008 04:58 PM, Ant sent:

isrrIP1BW1_2.bin@Cu_QtZK3pGsNCLut+zebpclPmO03z0+S

isrrIP1BW1_2.bin@Cu_QtZK3pGsNCLut+zebpclPmO03z0+S

isrrIP1BW1_2.bin@Cu_QtZK3pGsNCLut+zebpclPmO03z0+S

isrrIP1BW1_2.bin@Cu_QtZK3pGsNCLut+zebpclPmO03z0+S

If the Netgear RT311 router was removed from the equation while this testing occurred, then the Terayon TJ715x cable modem and Road Runner's outside plant has not been ruled out. While the send and receive levels have always been OK, I'm a bit surprised to see that your downstream SNR has taken a 4 dB turn for the worse. Perhaps while you weren't looking, the receive SNR was even worse too.

I wonder if you have a source for borrowing a cable modem for a day or so? If so, that's the next logical item to try. If you have any other services from your cable provider, I would ask if you receive any intermittent losses of service. e.g. If you have cable based telephone service, do you experience any voice dropouts from the opposite end.

If you have television service, do you experience losses of signal or video "tiling" that might coincide with your Internet failures? If you have any cable splitters or multiport couplers between your cable modem and your demarcation point, you might consider switching things around and disconnect/reconnect cables that haven't been touched in years. Tighten everything with a 7/16" open end wrench such that you use

*slightly* more force than your fingers are capable of. Some of your oldest F59 connector plugs might be overdue for replacement. RG-59 coax could be upgraded to good quality RG-6. Do you have any sort of on-site cable equipment that might contribute to this, or hasn't been mentioned?

Is your cable ingress from a utility pole or underground?

I suppose you could always set aside your own cable modem and rent one from your provider for a month or so. Comcast, in NoCal, rents ours out at $3/Mo.

What do you think about all this?

Pete

Hello Bill:

I'm fairly sure it would take me a month of Sundays to adapt the Pearl script from Terayon TJ715x use to Scientific Atlanta DPC2100 use. Are you the author, or do you know of anything like the script that's been written for that or the Linksys cable modems?

Thank you kindly,

Pete

[snipped]

I have not tried the router part. Are you saying the 4 dB change for SNR is that bad? I don't see any 4 value changes in the log parts I posted earlier.

I will probably go to the local office to ask for a modem exchange since this was a leased modem during Adelphia days.

I don't have any other cable services. Just Internet.

Underground. I know a mile away it, from my place, is on poles.

That's Perl not Pearl.

If the SA has similar type pages, it shouldn't be difficult at all and yes, I wrote it (basically a quick and dirty mainly to get my RF page). It's just a matter of retrieving the pages and parsing the data you want out of them. The Terayon was reasonably easy as you can probably see from the code - there's maybe 10-12 lines for each page that's specific to that page.

Last Thursday, September 30th, you said that your downstream receive sig was:

"Rx Power -1.9 dBmV Downstream SNR 33.4 dB"

The receive signal level is fine if it's generally 0.0 dBmV plus or minus 12 to 15 dB or so. YMMV. Your receive SNR /was/ fair at 33.4 dB, and would be even better at 35 dB. However you have reported your receive SNR to be as poor as 29.0 dB today and you might start seeing receive errors.

Sounds reasonable. I just hope you don't bring home a worse one. This happened to me with three Motorola HD cable receivers. Just as I was about to cancel all service, they unpacked a new model for me to "try just one more time". Now the HD TV is good.

Oh well... the other stuff above applies though.

I suppose that's what you get when you cast your perl scripts before bash swine... [Groan] I've had a few more beers and I should be very well behaved now. Thank you for correcting me.

I copied the file and was slightly disappointed to see you hadn't taken credit for what is obviously a significant undertaking. I very well may try to adapt your work towards use with a Linksys modem I'm getting. I have a sensitive part in my brain about plagiarized work but I suppose credit can still go to $Bill.

Thank you kindly.

Pete

I write scripts like that every day that the need arises - I wouldn't call it significant. I did the same for my Netgear RP614 router, but it's incomplete due to problems getting the popup status/statistics pages which I haven't had time to debug. If I need a schedule for my favorite sports team, I write another one, etc.

While I didn't give Ant authorization to disseminate it, I give you permission to use it as you will for your own use. ;)

If you need any help, let me know and I'll see what I can do. Basically what you need to do is take your browser to the page and dump the source out so you can see what you want to use of the HTML and what the page URLs are, etc.

Ah. I haven't had any new disconnections and here's my latest log: Fri Oct 3 05:20:31 PDT 2008

Diagnostics Page

RF Page Tx Power 40.0 dBmV Rx Power -1.0 dBmV Downstream SNR 32.8 dB Downstream MER 31.9 dB Tx Frequency 33000000 Hz Rx Frequency 705000000 Hz

Funny, I can't connect to my cable modem's Web pages again. I guess one minute gap isn't enough. Sheesh! Is that normal? I don't feel like powercycling my cable modem right now (just woke up). :D I'll do it later.

Haha. I wonder what they have these days. I have had Terayon (a non-DOCSIS model before the city's cable was upgraded a few years ago) and COM21 brands in the last.

Dang it! It looks my cable modem finally bit the dust or something. Since this morning, cable modem got disconnected when I was moving its cables and couldn't resynch a for few minutes even after recycling its power. I wiggled its coax cable connector a little and it synched.

At about 1:15 PM PDT, it went down again and didn't come back (probably have to go home and wiggle that coax cable again on the modem). I can't reach it either from outside: ... From 76.167.12.158 icmp_seq=1437 Destination Host Unreachable From 76.167.12.158 icmp_seq=1438 Destination Host Unreachable From 76.167.12.158 icmp_seq=1442 Destination Host Unreachable From 76.167.12.158 icmp_seq=1443 Destination Host Unreachable From 76.167.12.158 icmp_seq=1447 Destination Host Unreachable From 76.167.12.158 icmp_seq=1448 Destination Host Unreachable

--- 76.166.168.147 ping statistics ---

1450 packets transmitted, 0 received, +580 errors, 100% packet loss

So, 76.167.12.158 (gig14-1-indyca1-ars1.socal.rr.com) couldn't ping my IP address.

I think I will visit the local office tomorrow to exchange the modem. And tonight is a dial-up night. :(

And my cable modem came back alive by itself. Yup, history repeats again and it is signal related. Snipped log from the Perl script:

I am still planning to visit the local office to exchange modem tomorrow since the problems are crazy now. I really hope it is not a cable line issue!

Lost connections again earlier, but for a little short time. I think it will keep doing that. It's too late to go to visit the local office today.

On 10/03/2008 06:16 PM, Ant sent:

Snip, snip...

One of your phrases is key; "I wiggled its coax cable connector a little and it synced." A high probability exists that the RG59/RG6 cable, that terminates at your cable modem, is intermittently failing. I would consider asking your provider for a cable that can replace your existing one. I would *not* buy one from Radio Shack or the equivalent. The replacement will probably/should be made of high quality RG6 coax, and have the latest good quality crimped connectors. It certainly wouldn't hurt to request the provider give you the latest model cable modem with the latest firmware.

Hope to hear from you soon.

Is that the white coax cable (its printed texts say "Adelphia Communication E830032A (UL) CATV AWG 063840") that goes from outside to into the house? If so, then Adelphia's contractors set that line (hope it is a high quality) up back in March 2001. The house never had cable TV before so the holes had to be drilled, cables, stapled to outside walls, etc. This was back when Excite@Home was the service and Adelphia just took over Century Communications. I assume the contractors cabled from my room to downstair outdoor (no splitters and stuff).

Heh. I was trying to read the texts on the cable line in my room and my cable modem decide to lose synchronization. I had to wiggle the connector to the modem again. It's not loose either.

If the coax is one unbroken piece of cabling, from the demarcation point to the coaxial connector on your Terayon TJ715x, then it would be difficult for you to replace that cable. In that case, and if indeed you have an intermittent connection at the modem end where the male coaxial connector terminates the cable, then it might be best if your service provider sends a technician out to trim off a few inches of the coax and crimp a new male connector on. The other possibility is that the female connector, on the Terayon cable modem, has become intermittent and the most reasonable remedy is to replace the modem.

If indeed you exchange cable modems on Saturday, that should further isolate the trouble for you. Remember to exchange the wall wart power adapter too.

Yeah, I have the whole box, cable modem, and power AC (why do I want to keep it?) to return. I haven't had any more disconnections and weirdness so far since I last posted. I just hope the new modem isn't defected and stuff. :P Funny how I got my cable bill yesterday so I will save a stamp today by paying them in person later today.

Oh and I think it is the modem because during those quick disconnections (1 second long), I can't ping 192.168.100.1 like I said in my original post:

...

64 bytes from 192.168.100.1: icmp_seq=837 ttl=59 time=4.61 ms From 192.168.0.1 icmp_seq=838 Destination Host Unreachable From 192.168.0.1 icmp_seq=839 Destination Host Unreachable From 192.168.0.1 icmp_seq=840 Destination Host Unreachable From 192.168.0.1 icmp_seq=841 Destination Host Unreachable 64 bytes from 192.168.100.1: icmp_seq=842 ttl=59 time=5.56 ms ...

I don't think a problematic cable coax line would cause that? Would it? Sounds like a modem problem to me.

If you own that modem, why return it ? If it at least works somewhat, it gives a semi-workable spare.