Changed cable modem - now having LAN DHCP problems
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Their switches could be capable of running dhcpd I guess - but most of them are layer 2 so it would be a bit odd. Again look on a client - what does it show for the dhcp server?
They normally run their dhcp server on say one of their USGs Or their egdgerouter - what switch switch model exactly?
https://community.ubnt.com/t5/UniFi-Routing-Switching/DHCP-Server-in-US24-Switch/td-p/2103272
According to this there is no dhcpd on their switches... As I thought.. Again what does one of your clients that got this 192.168.10 address show you as its dhcp server?
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@johnpoz said in Changed cable modem - now having LAN DHCP problems:
Their switches could be capable of running dhcpd I guess - but most of them are layer 2 so it would be a bit odd. Again look on a client - what does it show for the dhcp server?
They normally run their dhcp server on say one of their USGs Or their egdgerouter - what switch switch model exactly?
https://community.ubnt.com/t5/UniFi-Routing-Switching/DHCP-Server-in-US24-Switch/td-p/2103272
According to this there is no dhcpd on their switches... As I thought.. Again what does one of your clients that got this 192.168.10 address show you as its dhcp server?
It is a model 'Switch 24'. Right now the only things latching onto .10 are the Unifi switch, a Nest thermosat, that I am aware of. The Unifi WAP went back to .1 after a hard reset. I tried the same reset on the switch, multiple times with no change.
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dude the switch can not run a dhcpd... So it aint the freaking switch!!!
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@johnpoz said in Changed cable modem - now having LAN DHCP problems:
dude the switch can not run a dhcpd... So it aint the freaking switch!!!
I am not saying that it is the switch, just that it is the only device that has not let go of the .10 address.
The ONLY thing that changed in this equation is the CABLE MODEM ... this setup has been stable for a couple of years until the modem was swapped, that's when the .10 showed up sporadically on the LAN. Most of the affected devices have been able to grab a .1 address after a reset of some sort, EXCEPT THE FREAKIN SWITCH.
geez -
Diagnostics > ARP Table
What MAC address is ARPing for the .10 address? Look up the OUI? What manufacturer is it? Find the device. Unplug it.
If that doesn't help, look at the switch mac-address-table. What port is that MAC address connecting through. Trace the cable. Unplug the device. (If the unifi switch lets you do such black magic)
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@derelict said in Changed cable modem - now having LAN DHCP problems:
Diagnostics > ARP Table
What MAC address is ARPing for the .10 address? Look up the OUI? What manufacturer is it? Find the device. Unplug it.
If that doesn't help, look at the switch mac-address-table. What port is that MAC address connecting through. Trace the cable. Unplug the device. (If the unifi switch lets you do such black magic)
I do not see the MAC address (of the switch) in the ARP table. When I run the Unifi Controller software the switch still shows to be at the .10 address. I cannot ping the switch at that address. The Unifi WAP had previously shown to be at another .10 address in the controller software... after a hard reset of the WAP it is showing to be at a .1 address and I can ping it etc, etc. The same is true for a handful of other IoT gadgets around the house that showed (through their own menus and displays) to be grabbing a .10 address... a reset/reboot managed to get them back on the .1 address.
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@nadeemabasa said in Changed cable modem - now having LAN DHCP problems:
I have same issue but now i got the solution from here.
What was the solution?
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There is not - he is just a spammer..
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You have a dhcpd running!! Find it... Run dhcpdump or sniff for the traffic.. Pfsense can do a packet capture on its lan and you will see the broadcast traffic..
And your cable modem is on a different layer 2.. Is it not??? Do you have your cable modem connected to your switch? Normally you would set your infrastructure devices to be static IP.