topic ISE will not let me add a switch in the same subnet in Network Access Control

ISE will not let me add a switch in the same subnet

Nick O — Thu, 24 Aug 2023 18:34:57 GMT

I am trying to add a switch to add another switch to my network devices on ISE. I have the switches in a x.x.254.0/24 subnet. ISE will not let me add a device in the same subnet.

Re: ISE will not let me add a switch in the same subnet

Mark Elsen — Fri, 25 Aug 2023 05:48:36 GMT

- What do you mean by that ? You can only add one NAD at a time ,

Re: ISE will not let me add a switch in the same subnet

Damien Miller — Fri, 25 Aug 2023 06:30:24 GMT

You should Ideally be adding your NADs as /32. ISE treats them as individual devices that way.

If you add a NAD as a /24 then all addresses in that subnet are treated as one device. There are use cases for using subnets but you can avoid your issue by changing the way you add them.

Re: ISE will not let me add a switch in the same subnet

balaji.bandi — Fri, 25 Aug 2023 06:46:13 GMT

Agreed @Damien Miller - try single IP rather subnet - that should fix the issue.

Re: ISE will not let me add a switch in the same subnet

Nick O — Fri, 25 Aug 2023 14:56:09 GMT

and that would not affect the way I have them set up on the switch? because I have them set up as a x.x.x.30/24. And if I am understanding what we are saying is that ISE will treat it as a single device with a /32. do I need to make the change on the switch as well?

Re: ISE will not let me add a switch in the same subnet

balaji.bandi — Fri, 25 Aug 2023 15:16:06 GMT

Not on the switch - Only ISE Side good enough.