Smart home devices disconnect after a week

Help
1

Expected Behaviour:

Using Pi Hole as DNS and DHCP server

Actual Behaviour:

We have several smart home devices that get knocked off our networks about once a week. They cannot connect and the only remedy is for the devices to be reconfigured from scratch, or to reset the router.

Certain items are not affected (Philips Hue, Arlo) as their hubs are physically connected to the router. Other devices that connect purely wirelessly (Yi Home Cameras, Amazon Smart Plugs, Ecobee, TP-Link Kasa Smart Plugs) are all affected within 24 hours of one dropping off.

I tried adding these devices based on their MAC address to have static DHCP lease. It still booted these off the network after a week.

Please advise! Sure, we can reset the router once a week but I'm wondering if it's a simple setting I'm overlooking?

Thanks,

Thomas

Debug Token:

https://tricorder.pi-hole.net/ctg67j28xa

2

You have two DHCP servers on your network. It is likely that you experience network issues on the clients when there lease expires

*** [ DIAGNOSING ]: Discovering active DHCP servers (takes 10 seconds)
   Scanning all your interfaces for DHCP servers
   Timeout: 10 seconds
   
   * Received 300 bytes from wlan0:192.168.1.246
     Offered IP address: 192.168.1.233
     Server IP address: 192.168.1.246
     Relay-agent IP address: N/A
     BOOTP server: (empty)
     BOOTP file: (empty)
     DHCP options:
      Message type: DHCPOFFER (2)
      server-identifier: 192.168.1.246
      lease-time: 120 ( 2m )
      renewal-time: 60 ( 1m )
      rebinding-time: 105 ( 1m 45s )
      netmask: 255.255.255.0
      broadcast: 192.168.1.255
      dns-server: 192.168.1.246
      domain-name: "lan"
      router: 192.168.1.1
      --- end of options ---
    
   * Received 300 bytes from eth0:192.168.1.180
     Offered IP address: 192.168.1.233
     Server IP address: 192.168.1.180
     Relay-agent IP address: N/A
     BOOTP server: (empty)
     BOOTP file: (empty)
     DHCP options:
      Message type: DHCPOFFER (2)
      server-identifier: 192.168.1.180
      lease-time: 120 ( 2m )
      renewal-time: 60 ( 1m )
      rebinding-time: 105 ( 1m 45s )
      netmask: 255.255.255.0
      broadcast: 192.168.1.255
      dns-server: 192.168.1.180
      domain-name: "lan"
      router: 192.168.1.1
      --- end of options ---
    
   DHCP packets received on interface lo: 0
   DHCP packets received on interface wlan0: 1
   DHCP packets received on interface eth0: 1

Solution would be to disable one of the DHCP servers.

3

That's strange, I turned off the DHCP on my router (see attached). Is there another place to do it? How do I track down where this second DHCP server is to turn it off?

Actually it looks like both of those IPs are for my Raspberry Pi. How is that possible?

Thank you for your help!!

Screenshot_20210126-073726|576x500

4

You're right. It appears as if both leases come from the Pi, one from eth0 and one from wlan0.
The lease-time offered seems quite short with 2 minutes, because you configured Pi-hole to hand out leases with 30 days

DHCP_LEASETIME=744

I'm not if the issue is related to Pi-hole, because your workaround is to restart the router and not Pi-hole. Does it get better, if you switch off Pi-hole's DHCP and switch on DHCP at your router again?

5

Thank you Yubi, I'm going to change the DHCP back to my router to see if this resolves the issue.

Moving forward, is fact that my Raspberry Pi is giving off two IPs a problem? How do I deactivate it as a DHCP if a I've already deactivated it through PiHole?

Thank you for your help!

6

If you disabled DHCP in Pi-hole your Pi should not give any DHCP leases anymore. Pi-hole is/was the DHCP server. There should not be any other DHCP server running on your Pi.

But let's check - please generate another debug log.

7

https://tricorder.pi-hole.net/mj6rup2cxg

Here you go!

8

Now there is only your router sending DHCP offers

*** [ DIAGNOSING ]: Discovering active DHCP servers (takes 10 seconds)
   Scanning all your interfaces for DHCP servers
   Timeout: 10 seconds
   
   * Received 300 bytes from eth0:192.168.1.1
     Offered IP address: 192.168.1.29
     Server IP address: N/A
     Relay-agent IP address: N/A
     BOOTP server: (empty)
     BOOTP file: (empty)
     DHCP options:
      Message type: DHCPOFFER (2)
      server-identifier: 192.168.1.1
      lease-time: 86400 ( 1d )
      netmask: 255.255.255.0
      router: 192.168.1.1
      dns-server: 192.168.1.1
      --- end of options ---
    
   * Received 300 bytes from wlan0:192.168.1.1
     Offered IP address: 192.168.1.30
     Server IP address: N/A
     Relay-agent IP address: N/A
     BOOTP server: (empty)
     BOOTP file: (empty)
     DHCP options:
      Message type: DHCPOFFER (2)
      server-identifier: 192.168.1.1
      lease-time: 86400 ( 1d )
      netmask: 255.255.255.0
      router: 192.168.1.1
      dns-server: 192.168.1.1
      --- end of options ---
    
   DHCP packets received on interface lo: 0
   DHCP packets received on interface eth0: 1
   DHCP packets received on interface wlan0: 1
9

Hopefully this resolves the issue! Are there any benefits to using my PiHole as the DHCP server over my router? If not, I will just leave it to my router to do it's thing.

Thank you Yubiuser!

10

It depends. Most routers will be fine working as DHCP servers. Pi-holes integrated a DHCP server as a workaround for those, who can not change the DNS server advertised by there router's DHCP server. So they had the ability to switch off the router's DHCP completely and use Pi-hole's instead. If everything is working with your router's DHCP, there is no need to switch.

11

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