Main Deco staying solid red after rebooting when working with Zmodo devices

Main Deco staying solid red after rebooting when working with Zmodo devices

Main Deco staying solid red after rebooting when working with Zmodo devices
Main Deco staying solid red after rebooting when working with Zmodo devices
2021-07-09 10:00:12 - last edited 2022-09-28 02:16:20
Tags: #Official #Highlighted Thread #WAN/LAN auto sensing
Model: Deco  
Hardware Version:
Firmware Version:

This Article Applies to:

All Deco models

 

Issue Description/Phenomenon:

In very rare cases, customer may find that the main Deco stays solid red after a power outage or firmware upgrade, or a simple reboot of the main Deco, the client devices in the Deco network won't be able to access the internet, despite the fact that the modem’s Internet was already back.

 

This issue occurs and ONLY occurs when the network meets 2 conditions:

1. Main Deco works in Router mode

2. The network onnection type is “Dynamic IP

 

And here is a typical network topology for the situation:

 

Background:

When debugging with the customer, we found out the IPv4 address on Deco has been changed to a new range when the issue happens. For example, it was a public IP assigned by ISP before, but it changes to 192.168.1.100/gateway 192.168.1.52. Based on the ARP checking, the gateway is the IP address of the Zmodo NVR.

Upon further checking, when the Smart DHCP device (like Zmodo NVR) loses internet, and it discovers that no DHCP Server is available in the network, because the main Deco is not up yet, it will turn on its own DHCP Server, starting to assign IP address all over the local network. In this case, the main Deco turns red, as port 2 doesn’t have internet.

 

The behavior of this Zmodo device is actually called “DHCP spoofing”, which will possibly bring the whole local network down. Moreover, when the Zmodo device was assigning IP addresses to other devices, the “lease time” option was set to 7 DAYS, whatever device got this kind of IP address, it will have to use this IP address at least for 7 days (unless you manually disconnect the Ethernet cable or Wi-Fi).

 

Available Solutions:

Actually, not only Zmodo NVR devices have a mechanism of Smart DHCP, which we also have an article about, but most Access Points or Range Extenders have this feature, so if you happened to have the same issue, please leave the model of the device in the comment below.

 

Here are two possible solutions for your reference:

1. Contact the Smart DHCP device manufacturer and request for disabling the Smart DHCP feature.

2. After a power outage, unplug the cable from port 2 first, only allowing the main Deco to connect through port 1, connect the cable of port 2 after the main Deco turns green.

  0      
  0      
#1
Options
2 Reply
Re:[Solution] Main Deco staying solid red after rebooting when working with Zmodo devices
2022-02-03 20:06:04

@TP-Link I have exactly the same problem

 

I have an M9+ as router and connected to my ISP modem in port 1. Port 2 is connected to a TL-SG108E switch. A Dahua NVR/CCTV is connected to the router and I suspect that it has Smart DHCP. I also have an Apple Airport Time Capsule connected to the switch.

 

Please see attached screenshot of the Dahua settings if you can determine if it has Smart DHCP.

 

Thanks.

  5  
  5  
#2
Options
Re:Main Deco staying solid red after rebooting
2022-10-19 11:06:51

  @TP-Link Recently my E4 in the office stops working when there is a power interruption. My main router will work but the rest of the decos won't have internet. I also have an M5 at home but it doesn't act up like this one. Let me know a work around because we are an ecommerce company and it's such a hassle that it takes days to reconnect to the internet. I'm so close to smashing the product and throwing it away.

  0  
  0  
#3
Options