vSAN1

I want to install vsan. Do I have to add a switch when installing 2 node vsan. Can't I directly connect the nodes? Also, is it necessary to install vCenter Server for VSAN?

You can review the guide below for 2 node vsan. He will answer all your questions.

vSAN 2 Node Guide | VMware

You can also connect VSAN nodes and use them without a switch. Therefore, it is a cost-effective solution. You need to have vCenter Server for VSAN. Yes, when you search from the internet, you will see that VSAN can be installed without a vCenter Server, but it is recommended by VMware to have a vCenter Server.

thank you man. Do you recommend 2 node vsan? Is it problematic?

2 node vsan is actively used and preferred. Just note that the hardware you will use is vsan ready. For VSAN, it is recommended to use VSAN Ready hardware.

Thank you very much! I will do my tests on nested esxi first.

You can create vsan using nested esxi. This is quite simple and there are a lot of resources.