I bought CAX30 from Costco 3 days ago and it is giving me nightmare.

[Exive]

I probably replying old tread but I am facing same issues.

I bought CAX30 from Costco 3 days ago and it is giving me nightmare. I recently upgraded my internet service that needs DOCSIS 3.1 so I replaced Netgear C7000v2 which was perfect, with CAX30.

I configured 99% same (99% because 802.11AX) as C7000v2 including DHCP settings. CAX30 is not allowing any change. I have network attached printer needed fix IP address. When I manually assign a printer to certain IP address, after few mins, entire devices connected to WiFi becomes "Connected, No Internet".

I changed 192.168.1.1 to 192.168.0.1. Changed range, updated latest firmware (1.4.10.10 that released few days ago), reset, hard reset, restore settings, contact ISP to re-provision my modem, check signal, and etc.

It seems faulty firmware ruining great hardware. DHCP is fail to assign IPv4 then assign IPv6. It tries to assign IPv4 (for 1-2 second successful) then lose connection. If you disable DHCP, and manually assign IP, Subnet, etc. It works. Unfortunately, not all devices can be set manually.

I saw last firmware release was 2021 and 1.4.10.10 released recently. Netgear should release another firmware to manage DHCP issue.

I read post from this community forum, and other forum and found this problem persist more than a year and Netgear isn't resolving the problem instead of replacing the model. Thus, I am done. I disconnected printer, IP cameras, and let CAX30 assign IP addresses to devices. Obviously, I am going to contact Costco to find out my option.

[FURRYe38]

What Ip address range did you set. I use 192.168.0.100 to .150 range. 

What browser are you using? 
For a printer, why not set a static IP address ON the printer that's out side of the above range. I do that for my 3 printers I have. 

[Exive]

I set 192.168.1.2 to 40 range. Does your CAX30 allow you to set IPs in 100 to 150 range? I changed as you described but no luck.

I use Firefox, Chrome, MS Edge, MS Edge Beta on macOS and Windows. Safari and Chrome on iOS and iPadOS.

There is no option to set a static IP address on my entry level HP Wireless Printer. Although it is possible to do for printer, I had been manually assigning IP addresses to my devices on Netgear routers that I owned in the past including C3000, and C7000v2. I wish I can do this on CAX30.

[FURRYe38]

I don't have a CAX30 however my CAX80 does. This is the range I always set and using on any modem or router I use. 

Had you tried a factory reset and setup from scratch and immediately go in and set 192.168.0.1 then set the IP address range to .100 to .200 apply and let the modem reboot. Then power ON the printer and let it connect, then set a IP address reservation for the printer. Save the setting then select the APPLY button after saving the setting. There should be a long pause or the modem might reboot. After the modem is back to ready, check the IP address on the printer. Try a reboot of the printer. It should have the reserved IP address. 

[Exive]

Yes, I did. And I got the replacement from Costco and new CAX30 (I updated with firmware 1.4.10.10) does same.

I lost hope. Switched back to C7000v2 and everything runs fine.

In the future, if someone find a way to fix CAX30 or Netgear provided new firmware that resolve the issue, please comment.

[FURRYe38]

I'll pass this on to NG for review. 

[Exive]

Thank you,

I just realized that my original post was actually mean to be a reply to other post.

https://community.netgear.com/t5/Cable-Modems-Routers/CAX30-DHCP-issues/m-p/2206204

And I see many post related to CAX30's DHCP issues, so I am not the only one. I hope Netgear can help us out.

[FURRYe38]

I recommend opening a support ticket with NG support:

https://my.netgear.com/support/contact.aspx

Can reference this thread link as well.