Re: CM1150V and AC1600 connection problems

smgillespie28 · ‎2022-08-05

Been using an AC1600 with wifi disabled as a wired router for my CM1150V for a while now with no troubles. Big storm last night (yes, plenty of surge protection). When power came back on, the AC1600 no longer sees the internet when connected to the CM1150V but when I connect my desktop computer (windows 10) to the CM1150V, it has no problem and I have full internet access. Computer can log into the AC1600 when plugged into it and the ac1600 seems to thinks it's not plugged into anything and I did try to use different network cables - even the one that works fine when the computer is directly connected to the CM1150V. Tried a factory reset on the AC1600 with no change. Haven't gone as far as a factory reset with the CM1150V.

Yes, I know one possibility is that the AC1600 died. But the problem is I also have an AC1750 and I'm seeing the exact same problem if I try to replace the AC1600 with the AC1750. And I know it's possible but I have a hard time believing both routers died at the same time. So it seems to me that for some reason a computer can connect to the cable modem but a router can not.

Appreciate any ideas or suggestions.

Thanks,
Stuart

FURRYe38 · ‎2022-08-05

AC1600 isn't a model number of a router.

Please post a copy and paste of the modems connection status page.

Be sure your using a good quality LAN cable between the modem and router. CAT6 is recommended.
What is the brand and model of the host wifi router connected to the modem?

Have the ISP check the signal and line quality UP to the modem. Be sure the ISP provisions the modem correctly.
Be sure there are no coax cable line splitters in the between the modem and ISP service box.
Be sure your using good quality RG6 coax cable up to the modem.
Be sure to power OFF the modem for 1 minute then back ON.
https://community.netgear.com/t5/Cable-Modems-Routers/General-info-and-Troubleshooting-for-Cable-Mod...
https://kb.netgear.com/24311/Power-level-guidelines-for-a-NETGEAR-cable-modem-router?article=24311
https://www.duckware.com/tech/solving-intermittent-cable-modem-issues.html

smgillespie28 · ‎2022-08-05

AC1600 isn't a model number of a router.

It's the name, not the model number. Model number is R6260

In house cabling and coax is the same that's been working well for several years.

Be sure to power OFF the modem for 1 minute then back ON.

Did that but will do it again.

Please post a copy and paste of the modems connection status page.

Is this what you're looking for?

FURRYe38 · ‎2022-08-05

Select the Cable Connection button you see on the modems web page. Copy and paste what you see on that page here.

smgillespie28 · ‎2022-08-05

Cable Connection

Frequency start Value

This field below allows you to modify the frequency the cable modem start with its scan during initialization and registration. Enter the new start frequency and restart the cable modem for it to take effect.

Starting Frequency

Starting Frequency: 0

Startup Procedure

Procedure	Status	Comment
Acquire Downstream Channel	651000000 Hz	Locked
Connectivity State	OK	Operational
Boot State	OK	Operational
Security	Enabled	BPI+
IP Provisioning Mode	Honor MDD	honorMdd(4)

Downstream Bonded Channels

Channel	Lock Status	Modulation	Channel ID	Frequency	Power	SNR	Correctables	Uncorrectables
1	Locked	QAM256	37	651000000 Hz	-6.7 dBmV	39.6 dB	12	0
2	Locked	QAM256	13	507000000 Hz	-3.3 dBmV	41.3 dB	8	0
3	Locked	QAM256	14	513000000 Hz	-3.3 dBmV	41.4 dB	3	0
4	Locked	QAM256	15	519000000 Hz	-3.6 dBmV	41.3 dB	2	0
5	Locked	QAM256	16	525000000 Hz	-3.8 dBmV	41.2 dB	7	0
6	Locked	QAM256	17	531000000 Hz	-4 dBmV	41.1 dB	2	0
7	Locked	QAM256	18	537000000 Hz	-4.3 dBmV	41 dB	2	0
8	Locked	QAM256	19	543000000 Hz	-4.5 dBmV	41 dB	7	0
9	Locked	QAM256	20	549000000 Hz	-4.8 dBmV	40.8 dB	4	0
10	Locked	QAM256	21	555000000 Hz	-5 dBmV	40.6 dB	3	0
11	Locked	QAM256	22	561000000 Hz	-5.2 dBmV	40.6 dB	7	0
12	Locked	QAM256	23	567000000 Hz	-5.6 dBmV	40.3 dB	6	0
13	Locked	QAM256	24	573000000 Hz	-6 dBmV	40.1 dB	10	0
14	Locked	QAM256	25	579000000 Hz	-5.7 dBmV	40.3 dB	6	0
15	Locked	QAM256	26	585000000 Hz	-5.2 dBmV	40.4 dB	9	0
16	Locked	QAM256	27	591000000 Hz	-5.1 dBmV	40.5 dB	5	0
17	Locked	QAM256	28	597000000 Hz	-5 dBmV	40.5 dB	7	0
18	Locked	QAM256	29	603000000 Hz	-5 dBmV	40.5 dB	9	0
19	Locked	QAM256	30	609000000 Hz	-5.3 dBmV	40.4 dB	5	0
20	Locked	QAM256	31	615000000 Hz	-5.5 dBmV	40.2 dB	10	0
21	Locked	QAM256	32	621000000 Hz	-5.7 dBmV	40.1 dB	6	0
22	Locked	QAM256	33	627000000 Hz	-5.9 dBmV	40 dB	7	0
23	Locked	QAM256	34	633000000 Hz	-6.1 dBmV	40 dB	13	0
24	Locked	QAM256	35	639000000 Hz	-6.3 dBmV	39.7 dB	6	0
25	Locked	QAM256	36	645000000 Hz	-6.6 dBmV	39.6 dB	13	0
26	Locked	QAM256	38	657000000 Hz	-6.8 dBmV	39.6 dB	11	0
27	Locked	QAM256	39	663000000 Hz	-6.6 dBmV	39.7 dB	12	0
28	Locked	QAM256	40	669000000 Hz	-6.5 dBmV	39.8 dB	11	0
29	Locked	QAM256	41	675000000 Hz	-6.6 dBmV	38.5 dB	17	0
30	Locked	QAM256	42	681000000 Hz	-6.5 dBmV	39.8 dB	19	0
31	Locked	QAM256	43	687000000 Hz	-6.5 dBmV	39.7 dB	11	0
32	Locked	QAM256	44	693000000 Hz	-6.6 dBmV	39.6 dB	18	0

Upstream Bonded Channels

Channel	Lock Status	US Channel Type	Channel ID	Symbol Rate	Frequency	Power
1	Locked	ATDMA	2	5120 Ksym/sec	16400000 Hz	38.5 dBmV
2	Locked	ATDMA	3	5120 Ksym/sec	22800000 Hz	39 dBmV
3	Locked	ATDMA	4	5120 Ksym/sec	29200000 Hz	39.5 dBmV
4	Locked	ATDMA	5	5120 Ksym/sec	35600000 Hz	40 dBmV
5	Not Locked	Unknown	0	0 Ksym/sec	0 Hz	0.0 dBmV
6	Not Locked	Unknown	0	0 Ksym/sec	0 Hz	0.0 dBmV
7	Not Locked	Unknown	0	0 Ksym/sec	0 Hz	0.0 dBmV
8	Not Locked	Unknown	0	0 Ksym/sec	0 Hz	0.0 dBmV

Downstream OFDM Channels

Channel	Lock Status	Modulation / Profile ID	Channel ID	Frequency	Power	SNR / MER	Active Subcarrier Number Range	Unerrored Codewords	Correctable Codewords	Uncorrectable Codewords
1	Locked	0 ,1 ,2 ,3	159	702000000 Hz	-5.9 dBmV	39.3 dB	1126 ~ 2969	120536736	20747665	0
2	Not Locked	0	0	0 Hz	0 dBmV	0.0 dB	0 ~ 4095	0	0	0

Upstream OFDMA Channels

Channel	Lock Status	Modulation / Profile ID	Channel ID	Frequency	Power
1	Not Locked	0	0	0 Hz	0 dBmV
2	Not Locked	0	0	0 Hz	0 dBmV

Current System Time:Fri Aug 05 16:02:37 2022
System Up Time:01:02:13

smgillespie28 · ‎2022-08-06

So one basic question is - for devices plugged into the CM1150V e-net ports - does the modem act at the DHCP server or is that managed upstream somewhere controlled by xfinity? That's my guess as to where things are failing.

Kitsap · ‎2022-08-06

You should have only one Ethernet connection to your CM1050V and that is your router. Your router provides DHCP services for the devices connected to your LAN. That includes both via Wi-Fi and Ethernet connections. Your router should be configured to enable "Use Router as DHCP Server."

smgillespie28 · ‎2022-08-06

You should have only one Ethernet connection to your CM1050V and that is your router. Your router provides DHCP services for the devices connected to your LAN.

Yes I know that's how it should work and that the modem only supports one device connected directly. But the router is not getting connected when it's that one device. While the computer when attached directly to the modem is connecting fine. Which brings me back to the last question. Where is the router supposed to get it's IP address from when it's the one device connected to the modem. From the modem - or somewhere further upstream?

If memory serves, I don't think this is new (the router not getting an IP address through some upstream DHCP server). I think I previously had the router setup to use a static IP address as a work around. Xfinity doesn't really support static IP addresses so maybe something about the storm made the old static ip invalid.

Kitsap · ‎2022-08-06

@smgillespie28 wrote:
Which brings me back to the last question. Where is the router supposed to get it's IP address from when it's the one device connected to the modem. From the modem - or somewhere further upstream?

Further upstream, in my R7800 configuration, Advanced -> Setup -> Internet Setup it shows Internet IP Address - Get Dynamically from ISP. See attached. I have IPv6 enabled and configured as Pass Through.

If you have not done so, power down your modem and disconnect both the coax and power cord. Then power down your router and disconnect the power cord. Wait several minutes, connect the coax to the modem, then the power cord and allow it start and stabilize. You can see when the leds are stable. Now connect the power cord to the router and allow it to boot up and stabilize. The servers at the ISP that assign IP addresses are not always fast and they vary from area to area. I have seen them take ten to fifteen minutes to assign the IP address to a router.

Connecting different devices to the modem via an Ethernet connection without rebooting the modem will not often result in an instant change. The same for making changes with the GUI, you may need to restart your system from scratch (see above) for the changes to take effect.

smgillespie28 · ‎2022-08-07

Thanks I appreciate the help - but I've "restarted from scratch" more times than I can count. The R6260 never worked well with the CM1150V (or maybe never worked well with the xfinity service). I decided it's time for it to go away. I don't want to fight with it any more.

And since it's pretty much impossible to get a non-wireless router on short notice, and I didn't want to risk getting another wireless router that couldn't connect through the CM1150V, I decided to replace the CM1150V with a Moto MT7711. I don't need the wireless router included in the modem - but I do need the built in router capability which the CM1150V didn't have. Not sure what the point was of having 4 ports if only one device could be connected. If nothing else, it certainly was misleading when I initially bought it.

Funny thing is, since I was curious - the R6260 couldn't connect to the MT7711 either. Fortunately, the R6400 could even though it also couldn't connect to the xfinity service through the CM1150V.

Again, thanks for trying.