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user_lgkvkk
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2 Messages

Thursday, July 10th, 2025

router arp table

My xfinity router will not recognize devices for up to several minutes, even after giving them IP addresses via dhcp. This in turn affects software which is trying to use these devices. Example is Tidal using Tidal Connect to a Wiim streaming device. The devices also just disappear for no good reason and it usually takes a router restart to see them again, but it still take up to several minutes to see them after restart. I'm told by tech support this is normal for "Consumer" grade appliances. What's the firmware problem with these routers? Please understand I know what I'm doing. I've been building, configuring, troubleshooting, and maintaining networks since before microsoft windows was invented. I want a real answer from someone with knowledge. The techs I've talked to either have no clue what I'm talking about, or the upper tier support people won't call me back after I'm told they'll call within an hour. Been waiting 2 days for that call!

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1 month ago

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XfinityGabriel

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2.5K Messages

1 month ago

 

user_lgkvkk, Hi there! Thanks for taking the time out of your day to reach out. As an internet subscriber myself, I can understand the inconvenience caused by those devices not being recognized or disappearing. I am sorry to learn about this experience with never recieving those follow up calls. You are awesome for your business and expertise in this. You've reached the right place. Our team of experts is happy to help in any way we can over social media. These issues can happen due to a few potential reasons. These include issues with the device's network adapter, DHCP server configuration, or physical connection problems. Additionally, the router's DHCP lease time, the time it holds an IP address assignment, can cause delays if it's set too short or if the device is attempting to reconnect after a long period of inactivity. 
 
Here's a more detailed breakdown of the possible causes:
1. Device-Side Issues:
  • A faulty network interface card (NIC) or outdated drivers on the device can interfere with the DHCP process. 
     
  • Incorrect settings on the device or the router's DHCP server can prevent proper communication and IP address assignment. 
     
  • Ensure the device is properly connected to the WiFi network and that WiFi is enabled. 
     
2. Router-Side Issues:
  • DHCP Lease Time:
    The router's DHCP lease time determines how long it holds an IP address assignment. If the lease time is short, the device may need to renew its IP more frequently, potentially causing delays. 
     
  • Restarting the router can sometimes resolve temporary issues with the DHCP server. 
     
  • If a device is assigned a reserved IP address that was previously assigned to another device, it could cause delays or prevent the device from connecting. 
     
  • Outdated router firmware can sometimes cause connectivity issues. Check for firmware updates from Xfinity. 
     
3. Network Infrastructure Issues:
  • Poor connections, damaged cables, or excessive splitters can disrupt the signal and affect the DHCP process. 
     
  • Other devices or neighboring WiFi networks can cause interference and slow down the network, including the DHCP process. 
     
Troubleshooting Steps:
  • Restart the Device:
    Power cycling the device can clear any temporary issues with the network adapter. 
     
  • Restart the Router:
    Restarting the router can help resolve temporary issues with the DHCP server. 
     
  • Check Physical Connections:
    Ensure all cables are securely connected to the router, modem, and wall outlet. 
     
  • Verify WiFi Settings:
    Confirm that the device is connected to the correct WiFi network and that WiFi is enabled. 
     
  • Check for Firmware Updates:
    Check for and install any available firmware updates for your Xfinity router. 
     
  • Review DHCP Settings:
    Review the router's DHCP settings and lease time, if available. 
     
  • Consider DHCP Reservations:
    If you consistently have issues with specific devices, consider setting up DHCP reservations in the router's settings. 
     
    If the issue persists, please feel free to send us a direct message with your first/last name and full address so we can ensure we pull up the correct account to take a look at what's going on. You can start by clicking the "direct message" icon in the upper right page of our forum page. Once you click on that, input our shared handle Xfinity Support to send us a direct message.

 

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user_lgkvkk

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2 Messages

None of the above has anything to do with this issue. The issue is not related to the WIFI. It's the way the router deals with ALL the devices connected to my network. I have many device hard wired, and many of these are configured as static IP. Those are the ones that always have the problem. The Xfinity Router and phone app says these static IP devices are offline all the time. Occasionally they show up, then if I do a refresh of the app they disappear. They may come back later on, maybe not. The router is not keeping track of all the devices on the network as it should. THAT is the real problem!

I'm looking at the router live right now. I have 2 Wiim devices (I have 3) powered up with static IP and they don't show up as a connected device in the router. My 2 hardwired laptops currently running as DHCP show up just fine. I think you've assumed everything is going to be DHCP and that is NOT how a router is supposed to work. It needs to deal with ALL the devices correctly or stuff doesn't work. As is the case in my home. Please fix this issue ASAP!

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1 month ago

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XfinityEva

Official Employee

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1.9K Messages

Thank you for getting back to us. Since you are still experiencing issues at tis time, can you please send us a direct message with your full name and service address for further assistance? We can circle back here once resolved to update the community with the resolution. 

 

  • Make sure you are signed in here in the Xfinity Forum. Click "Sign In" if necessary
  • Click the "Direct Message" icon (square chat icon in the upper right corner of your screen next to the bell icon)
  • Click the "New message" (pencil and paper) icon
  • Type "Xfinity Support" in the "To:" line and select "Xfinity Support" from the drop-down list which appears. The "Xfinity Support" graphic replaces the "To:" line
  • Type your message in the text area near the bottom of the window
  • Press Enter to send it
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1 month ago

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