MX64 DHCP Issue handing out incorrect addresses

[AEgirSys]

I have just started having problems after my last update (MX 13.33). I have define a 10.10.1.X range but periodically i get a 10.139.29.X address assigned to my devices. this is some of the issues

1) hands out a 10.139 address and shows it in the dashboard->clients

2) hands out a 10.139 address but shows a 10.10 in the Dashboard->clients (tracked by MAC address)

Neither address is accessible - This has just started happening since the update. 

any help will be greatly appreciated. 

roger...

[Adam]

Do you have the 10.139.x subnet as a vlan?  Are the ports attached to the clients in question just access ports with a data vlan or do you also have a voice vlan?  I've had some luck using the DHCPExplorer tool.  It is a free download that can help troubleshoot DHCP stuff.  I wouldn't initially worry about how stuff shows up in dashboard since that can be delayed and inaccurate.  If you can get your hands on a client or two having the issue it would be most ideal.  From that client see if you can ping the gateway etc...

[AEgirSys]

Adam, 

Thank you for the reply- the 10.139 is not defined anywhere in the network - the other subnet is a 172 subnet - this network is data only so no voice traffic. i currently have three tablets i am developing software on that are experiencing this issue, as well as 1 amazon echo, the google home has not been affected (yet). this has happened on both WiFi and lan based devices - will download DHCPExplorer and see what it shows. 

roger...

[PhilipDAth]

It is almost certain you have another DHCP server on your network.

Use "ipconfig" and find out your default gateway.  Then use "arp -a" to find out the MAC address of the default gateway.  If this device plugs into directly to the MX you will be able to put the MAC address into the clients list to find out what it is.

Otherwise you will need a managed switch to track it down.