MS120 handing out a random private address (192.168.45.0)

[peterwarwick]

Hi All,

Just wondering if anyone has seen this issue before?  I have a user who usually works off of the wireless which hands out an address on the LAN (192.168.1.0/24).  For one reason or another, he was not able to connect to the wireless so we have patched him temporarily.

Upon patching we found that he was getting a random private address not associated with any VLAN on the corporate network.  Initially, I thought that the issue could be local and had the user show me that there was no static IP's on the network adapters of the PC. Normal ipconfig/release && ipconfig/renew had no effect. 

I have assigned him a static IP temporarily so he can work, but I still see the switch trying to hand out a 192.168.45.0 address.

Any ideas?

MS120 switchport access config

thanks,

Pete

[peterwarwick · Accepted solution]

Found out someone had started a DHP server on the network using the tag of 1, which was causing the conflicts.

All sorted now.

[BlakeRichardson]

@peterwarwick  I suggest you setup the below alert within your dashboard.

[jdsilva]

You can also lock down your network to known authorized DHCP servers only, completely preventing rogues from ever happening.

https://documentation.meraki.com/MS/Monitoring_and_Reporting/MS_DHCP_Servers