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New Asus ZenWiFi BE5000 Router will not get IP from new S34 Modem

  • August 7, 2025
  • 4 replies
  • 110 views
I
The Many
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Today I replaced my Spectrum Modem with a new S34. and had Spectrum activate it. Hooked to my laptop I get an IP and all works well, but hooked to the new Asus ZenWiFi BE5000 I get no IP. Hooked to an old Ubiquity UDM it works perfect so for the moment my client lives with the UDM. Took the ZenWiFi home and plug it in my network and it comes up and works perfectly so I know the router can accept an IP and the Modem can supply an IP, but why can’t the two new boxes work together.  The Spectrum Tech claimed that the modem was not showing that the ZenWiFi was showing as plugged in when I plugged it in. 

Background, the Spectrum modem had been with fine with a TPLink WIFI 5 modem for a couple of years but apparently also stopped getting IPs yesterday, Which is why we started replacing stuff.

Best answer by SURFboard Moderator

Since you confirmed that your laptop gets a connection when directly connected to the modem, please make sure to use only an Ethernet connection to the modem.

Also, whenever you switch Ethernet cables or devices connected to the modem, be sure to restart the cable modem.
This helps ensure the modem assigns a proper IP address to your router or device.

 

This topic has been closed for replies.

4 replies

S
Wi-Fi Warriors
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Since you confirmed that your laptop gets a connection when directly connected to the modem, please make sure to use only an Ethernet connection to the modem.

Also, whenever you switch Ethernet cables or devices connected to the modem, be sure to restart the cable modem.
This helps ensure the modem assigns a proper IP address to your router or device.

 

SURFboard Community Moderator Team
I
The Many
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  • iraThe Many
  • Author
  • The Many
  • August 11, 2025

Did you think any of what you said was helpful?

plemans
Juggernaut
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  • plemansJuggernaut
  • Juggernaut
  • August 13, 2025

If the laptop worked, the device works. 

the problem with most ISP’s is that they only provide a single public ip address for residential setups. 

So even though the modem has 2x ethernet ports, only 1 gets that IP address. 

Meaning only 1 connects to the internet. If the laptop worked while connected, the modem works and is assigning it to the laptop. 

so power off the router and the modem. Make sure nothing is connected to the modem and power it on. give it a couple minutes to boot. then connect the router to it. Boot up the router and run its internet setup. 

Don’t connect anything else to the S34 other than the router. 

Current setup: Netgear CM3000-->Netgear RBE973S-->2.5gig tp-link switch, Xfinity 2.4gig/350mbps
I
The Many
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  • iraThe Many
  • Author
  • The Many
  • August 13, 2025

So I only plugged the laptop into the modem when the router didn’t work and I wanted to see if the modem would assign anything an IP. I always power off the modem when switching devices and never plug more than one cable at a time into the modem. 

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