Client IP address in different subnet

[goombawaho]

One of my customers has an Asus router. I was looking at the clients connected to the device. It's a 192.168.2.X network. And I see the following in the list of clients (see attached picture) 192.168.101.X devices. What is going on?

 

[spamjim]

A router could assign any number in the defined IP pool range. If we were limited to interacting with our own subnet, the internet would not work.

https://www.asus.com/us/support/FAQ/1011703/

 

[guitarzan]

Maybe a wifi guest network using a different subnet?

 

[goombawaho]

There's only one subnet and one dhcp server (as it should be) and it's on the ASUS router. Therefore all clients should be in that same subnet. No VLANS or anything fancy.

 

[xwb]

If you can get to the IPV4 alternative configuration tab, you might find that it has been added as an alternate address. Some PCs have a two addresses so they can access different subnets

 

[goombawaho]

I set up all of these computers. The ones that have static ip addresses are not among those with the odd subnet. And no device were set up with dual network cards. I'll just wait until I'm there and take a look at the config. Interestingly, these are all devices that are not the "core PCs". These are ipads or phones that people brought in and connected to the network on their own. I know - not a good idea. But the owner doesn't care.

 

[biglebowski]

check the subnet mask, a /16 would give you 192.168.0.1 through to 192.168.255.254

In the asus you may have got the 3rd octet wrong and put 255.255.0.0 instead of 255.255.255.0

 

[goombawaho]

No, it's correct and remember that I didn't show you the other 40 clients that have the correct IP address in the photo.