ISE HA pair ( between small and medium size vm)

[Nasir.Niazi]

I have two virtual ISE nodes (PAN or MNT), one has a small VM license (12g ram, 12 core)  the other one has a medium VM license (16g ram, 16 core). Can I configure HA pair? ( I know best practice is to have equivalent hardware resource)

[Damien Miller · Accepted solution]

Mixing node sizes like this will work fine, you just need to use the smaller of the two nodes as far as scaling numbers are concerned. 

I'm not sure the node sizes you reported are correct though, there is no ISE node hardware/vm profile with 12 GB of memory. The smallest nodes supported for production today are all at least 16 GB in 2.x/3.0, and 3.1 requires at least 32 GB of memory. 

[Nasir.Niazi]

Lets say I want to upgrade from small to medium, but I cant afford two Medium ISE. I just can afford one, so I want to deregister secondary PAN or MNT increase RAM, CPU, install fresh medium VM, then reregister, and promote to primary. 

Yeah the ram and CPU is just an example, 

[Marcelo Morais · Accepted solution]

Hi @Nasir.Niazi ,

 as @Damien Miller already said, the answer is Yes. Please take a look at: Performance and Scalability Guide for Cisco Identity Services Engine. (for Hardware Platforms and ISE Deployment).

Hope this helps !!!