Just recently installed the Netgear CM1200 modem to support the 1G Internet service I upgraded to from my ISP "RCN" here in Pennsylvania. I also have an RAX70 Netgear Nighthawk (also new) attached and both are brand new. I've had 2-3 instances of dropped connections on my CM1200 over the last week since I installed it. Both times the DOWNSTREAM light on the modem was just flashing green and we had no service in the house. Both times I turned off the modem by using the power button, kept it off for a minute, turned it back on. And both times within a minute or so the modem would eventually go all green solid lights and we'd hear the pings on our equipment that the Internet service was back on. I did read other posts that some people have had the same issue. I read some said to check wiring, splitters, etc. Note that this is an upgrade from our previous setup which was a CM600 Netgear Modem with a Netgear Nighthawk X8 R8500 which both worked flawlessly when we had the 250M Internet service from RCN. So the wiring is not an issue. Below are the event logs from the issue last night. If anyone has any suggestions I would appreciate it. Obviously I want to make this work but I can't afford to continue manually resetting the modem to get things up and working every time. It shouldn't be that way. Thanks in advance. - Brian TimePriorityDescriptionFri Jan 22 11:28:26 2021Warning (5)REG-RSP-MP Mismatch Between Calculated Value for P1.6hi Compared to CCAP Provided Value;CM-MAC=08:36:c9:a4:46:d8;CMTS-MAC=2c:0b:e9:14:b0:e9;CM-QOS=1.1;CM-VER=3.1;Fri Jan 22 11:28:24 2021Notice (6)DS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1 2 3.;CM-MAC=08:36:c9:a4:46:d8;CMTS-MAC=2c:0b:e9:14:b0:e9;CM-QOS=1.1;CM-VER=3.1;Fri Jan 22 11:28:19 2021Notice (6)TLV-11 - unrecognized OID;CM-MAC=08:36:c9:a4:46:d8;CMTS-MAC=2c:0b:e9:14:b0:e9;CM-QOS=1.1;CM-VER=3.1;Fri Jan 22 11:28:19 2021Error (4)Missing BP Configuration Setting TLV Type: 17.9;CM-MAC=08:36:c9:a4:46:d8;CMTS-MAC=2c:0b:e9:14:b0:e9;CM-QOS=1.1;CM-VER=3.1;Fri Jan 22 11:28:19 2021Error (4)Missing BP Configuration Setting TLV Type: 17.8;CM-MAC=08:36:c9:a4:46:d8;CMTS-MAC=2c:0b:e9:14:b0:e9;CM-QOS=1.1;CM-VER=3.1;Fri Jan 22 11:28:19 2021Error (4)Missing BP Configuration Setting TLV Type: 17.7;CM-MAC=08:36:c9:a4:46:d8;CMTS-MAC=2c:0b:e9:14:b0:e9;CM-QOS=1.1;CM-VER=3.1;Fri Jan 22 11:28:19 2021Error (4)Missing BP Configuration Setting TLV Type: 17.6;CM-MAC=08:36:c9:a4:46:d8;CMTS-MAC=2c:0b:e9:14:b0:e9;CM-QOS=1.1;CM-VER=3.1;Fri Jan 22 11:28:19 2021Error (4)Missing BP Configuration Setting TLV Type: 17.5;CM-MAC=08:36:c9:a4:46:d8;CMTS-MAC=2c:0b:e9:14:b0:e9;CM-QOS=1.1;CM-VER=3.1;Fri Jan 22 11:28:19 2021Error (4)Missing BP Configuration Setting TLV Type: 17.4;CM-MAC=08:36:c9:a4:46:d8;CMTS-MAC=2c:0b:e9:14:b0:e9;CM-QOS=1.1;CM-VER=3.1;Fri Jan 22 11:28:19 2021Error (4)Missing BP Configuration Setting TLV Type: 17.3;CM-MAC=08:36:c9:a4:46:d8;CMTS-MAC=2c:0b:e9:14:b0:e9;CM-QOS=1.1;CM-VER=3.1;Fri Jan 22 11:28:19 2021Error (4)Missing BP Configuration Setting TLV Type: 17.2;CM-MAC=08:36:c9:a4:46:d8;CMTS-MAC=2c:0b:e9:14:b0:e9;CM-QOS=1.1;CM-VER=3.1;Fri Jan 22 11:28:19 2021Error (4)Missing BP Configuration Setting TLV Type: 17.1;CM-MAC=08:36:c9:a4:46:d8;CMTS-MAC=2c:0b:e9:14:b0:e9;CM-QOS=1.1;CM-VER=3.1;Fri Jan 22 11:28:18 2021Warning (5)DHCP WARNING - Non-critical field invalid in response ;CM-MAC=08:36:c9:a4:46:d8;CMTS-MAC=2c:0b:e9:14:b0:e9;CM-QOS=1.1;CM-VER=3.1;Time Not EstablishedNotice (6)Honoring MDD; IP provisioning mode = IPv4

The frustration dealing with RCN saying their side ws fine and continued drops on the CM1200 (not one, but TWO CM1200's with the same issue) forced me to try a different modem. I fully believe the issue is firmware/software related between RCN's network and the modem, but I don't have time for them to figure it out. That being said, the other night I went out and purchased an Arris SB8200 (which I believe is the same modem RCN would install if you lease/rent it from them) and it's worked flawlessly for the past week. I'm a Netgear guy but my patience on these issues just wore thin. I still have my RAX70 Nighthawk on the other end and that works great, but unfortunately we had to go in a different direction on the modem side. Appreciate everyone's help. Sorry it didn't work out with the CM1200.

One other bit of info from RCN. I reached out to them via Twitter and they sent the question about the 32-channels to their technical group. Here's their answer: "We use whatever channels we need to use to accomplish the needed speed. If pressed, for RCN, we usually shift into OFDM channels after 16, though this can vary."

Ok, glad they seem to have got it working better. I guess some ISPs maybe using 16 channels vs 32. If that works for them then I guess it works. Possible there compressing signals into 16 channels. Sounds like it maybe mosty a connection issue since they reported finding bad connections on there side. Also I would chreck the modems FW as well. v1s seem to have more problems. I'm on v2. I believe there is a v3 aswell. Hope it keeps working. bcooper27 wrote:RCN Technician came by today. He initially checked the signal on the cable in my office to check for errors and all looked good...no issues. He checked the connections outside my home and found the connection at the pole and the connections on either side of the underground cable were 'bad.' He also said there was a splitter on the outside of the home that didn't need to be there. She he replaced all the connections and took out the splitter and he did say that the signal was improved (he said it went from a +2 to a +7 whatever that meant. He still thinks that, although he fixed some things to bring it up to spec, the issues we're having are equipment related. He said IF it continues to happen, then 99% sure it's the modem. So I'm going to monitor this for a day or two and see what happens. And regarding the question about the 16 locked channels vs. 32 channels, he said that some ISP's do 32 channels but RCN is different and they do not. As soon as I started to ask about it, he started shaking his head NO (like he knew I what I was going to ask) so it sounds like an RCN-thing. Bottom line is I'm showing ~900M speed on the download side off my router so I'm getting the bandwidth. Guess I don't care if it's 32 or 16 channels....as long as it stays UP and I fix this possible modem issue. We'll see

So today I took the CM1200 back to Best Buy and told them we've checked everything and the RCN tech even made connection replacements on the cable and sees everything running perfect on their side, but the modem continued to have Internet dropping issues. I told them that after talking with RCN, we figured that if it continued dropping after they made sure everything was fine on the network side, it would HAVE to be equipment issues so I wanted to replace it. Best Buy swapped it out for another CM1200 and I installed that today about 3:30pm ET. About 10mins ago (10:10pm or so) the new one did the SAME thing. Internet dropped, the download light was flashing again and I had to reboot to get it back up and running. SAME problem. Checking the logs it showed same errors as previously shown in posts above. I can't believe I had two bad modems. I got them from two different Best Buy stores, not that that makes a difference, but it could. I guess there's a possibility of me getting two bad ones but the odds have to be astronomical. I fully believe there's a config issue of some sort, quite possibly the firmware. Right now the modem shows Firmware version V2.02.05 which I think is the latest. If I had to bet money, this is the issue. So this begs the question, how do I get the modem on a different version to test it out? Is this driven by the ISP RCN? Again, appreciate the help as I continue trying to troubleshoot this problem. I don't want to give up on the Netgear Modem....I've had good luck with all of my Netgear equipment over the years and I want to exhaust every effort before I throw in the towel.

It is driven by the ISP in terms of firmware. Maybe DarrenM could help out with ISP specifics on modems

bcooper27

Star

Jan 22, 2021

CM1200 Modem Dropping Connection

Just recently installed the Netgear CM1200 modem to support the 1G Internet service I upgraded to from my ISP "RCN" here in Pennsylvania. I also have an RAX70 Netgear Nighthawk (also new) attached and both are brand new. I've had 2-3 instances of dropped connections on my CM1200 over the last week since I installed it. Both times the DOWNSTREAM light on the modem was just flashing green and we had no service in the house. Both times I turned off the modem by using the power button, kept it off for a minute, turned it back on. And both times within a minute or so the modem would eventually go all green solid lights and we'd hear the pings on our equipment that the Internet service was back on.

I did read other posts that some people have had the same issue. I read some said to check wiring, splitters, etc. Note that this is an upgrade from our previous setup which was a CM600 Netgear Modem with a Netgear Nighthawk X8 R8500 which both worked flawlessly when we had the 250M Internet service from RCN. So the wiring is not an issue.

Below are the event logs from the issue last night. If anyone has any suggestions I would appreciate it. Obviously I want to make this work but I can't afford to continue manually resetting the modem to get things up and working every time. It shouldn't be that way. Thanks in advance. - Brian

Time	Priority	Description
Fri Jan 22 11:28:26 2021	Warning (5)	REG-RSP-MP Mismatch Between Calculated Value for P1.6hi Compared to CCAP Provided Value;CM-MAC=08:36:c9:a4:46:d8;CMTS-MAC=2c:0b:e9:14:b0:e9;CM-QOS=1.1;CM-VER=3.1;
Fri Jan 22 11:28:24 2021	Notice (6)	DS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1 2 3.;CM-MAC=08:36:c9:a4:46:d8;CMTS-MAC=2c:0b:e9:14:b0:e9;CM-QOS=1.1;CM-VER=3.1;
Fri Jan 22 11:28:19 2021	Notice (6)	TLV-11 - unrecognized OID;CM-MAC=08:36:c9:a4:46:d8;CMTS-MAC=2c:0b:e9:14:b0:e9;CM-QOS=1.1;CM-VER=3.1;
Fri Jan 22 11:28:19 2021	Error (4)	Missing BP Configuration Setting TLV Type: 17.9;CM-MAC=08:36:c9:a4:46:d8;CMTS-MAC=2c:0b:e9:14:b0:e9;CM-QOS=1.1;CM-VER=3.1;
Fri Jan 22 11:28:19 2021	Error (4)	Missing BP Configuration Setting TLV Type: 17.8;CM-MAC=08:36:c9:a4:46:d8;CMTS-MAC=2c:0b:e9:14:b0:e9;CM-QOS=1.1;CM-VER=3.1;
Fri Jan 22 11:28:19 2021	Error (4)	Missing BP Configuration Setting TLV Type: 17.7;CM-MAC=08:36:c9:a4:46:d8;CMTS-MAC=2c:0b:e9:14:b0:e9;CM-QOS=1.1;CM-VER=3.1;
Fri Jan 22 11:28:19 2021	Error (4)	Missing BP Configuration Setting TLV Type: 17.6;CM-MAC=08:36:c9:a4:46:d8;CMTS-MAC=2c:0b:e9:14:b0:e9;CM-QOS=1.1;CM-VER=3.1;
Fri Jan 22 11:28:19 2021	Error (4)	Missing BP Configuration Setting TLV Type: 17.5;CM-MAC=08:36:c9:a4:46:d8;CMTS-MAC=2c:0b:e9:14:b0:e9;CM-QOS=1.1;CM-VER=3.1;
Fri Jan 22 11:28:19 2021	Error (4)	Missing BP Configuration Setting TLV Type: 17.4;CM-MAC=08:36:c9:a4:46:d8;CMTS-MAC=2c:0b:e9:14:b0:e9;CM-QOS=1.1;CM-VER=3.1;
Fri Jan 22 11:28:19 2021	Error (4)	Missing BP Configuration Setting TLV Type: 17.3;CM-MAC=08:36:c9:a4:46:d8;CMTS-MAC=2c:0b:e9:14:b0:e9;CM-QOS=1.1;CM-VER=3.1;
Fri Jan 22 11:28:19 2021	Error (4)	Missing BP Configuration Setting TLV Type: 17.2;CM-MAC=08:36:c9:a4:46:d8;CMTS-MAC=2c:0b:e9:14:b0:e9;CM-QOS=1.1;CM-VER=3.1;
Fri Jan 22 11:28:19 2021	Error (4)	Missing BP Configuration Setting TLV Type: 17.1;CM-MAC=08:36:c9:a4:46:d8;CMTS-MAC=2c:0b:e9:14:b0:e9;CM-QOS=1.1;CM-VER=3.1;
Fri Jan 22 11:28:18 2021	Warning (5)	DHCP WARNING - Non-critical field invalid in response ;CM-MAC=08:36:c9:a4:46:d8;CMTS-MAC=2c:0b:e9:14:b0:e9;CM-QOS=1.1;CM-VER=3.1;
Time Not Established	Notice (6)	Honoring MDD; IP provisioning mode = IPv4

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CM1200 Modem Dropping Connection

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