topic Re: IP Confict Alarms in Cloud Networking Platform

IP Confict Alarms

bxdobs — Fri, 17 May 2024 00:32:23 GMT

Z3 stand alone network being used for a club has been experiencing a number of IP Conflict alarms by seemingly one device ... the MAC within the Client list suggests this is some kind of android device ... the logs suggest it is requesting DHCP services to assign its IP Address ... The issue is it is using addresses already assigned/in use ... fairly certain Meraki would NOT issue an address that it has already assigned. Added a blocking policy to this device but it keeps moving to another in use IP ... used arp -a to try and track this device but every time I ping this device it disappears from the arp list

are there any network/wifi tools that could help track this device down?

Re: IP Confict Alarms

aleabrahao — Fri, 17 May 2024 01:23:49 GMT

Look, the Meraki will not assign the same IP to different Macs, the probability is that some device has a fixed IP.

To identify devices you can use the client list and the ARP table, there is not much secret.

Re: IP Confict Alarms

VictorYang — Fri, 17 May 2024 04:28:25 GMT

Agreed that the Z3 will not assign the same IP to a different mac address. But if the android device could use the IP it like even if it's duplicated with others.
You cannot block a device to connect to an SSID. The block policy only applied after it connected. If you select those issue is created by the same device with the same Mac address. You may assign a fixed IP to it then assign the block policy. But if the device doesn't take DHCP and insist to user its' own static IP. You would need to find the device and correct the settings.

Re: IP Confict Alarms

Philip D'Ath — Sun, 19 May 2024 21:31:42 GMT

What's the bet it is something to do with MAC randomisation.

The Android starts off using a private MAC address, gets a DHCP address, and then changes to a non-private MAC. That would make it look like two different MAC addresses where trying to use the same IP address.