I've been wanting to set up a cheaper home virtual environment. basically similar to what most businesses run but cheaper, less power hungry, and wont consume a corner of my apartment. I understand one way is buy used but that requires some social engineering and luck. The fact is i don't really need need much performance. probably 2 virtual hosts, some switches, and some storage. i'll probably set up some domain controllers, different network services, some application servers to practice stuff like setup and dealing with migration. i might even just pull the plug on one host s simulate a outage situation.
What are some features to look out for on the hardware i will be getting to try a bunch of different stuff.
First off, if you are talking just a virtual lab to experiment with, and not run any meaningful workloads you really don't need that much. The beauty of it is, with nested virtualisation you don't even need two hosts. You can create VM's inside VM's or run VM's as container hosts.
Going this route means that even with a modest i5 and 16GB setup you can learn a lot e.g. how to build clusters etc.
For a half decent single workstation lab set up going for something with 8 threads and 32GB a couple of SSD's and a couple of HDD would be ideal.
So creating virtual networks and mapping physical NIC's to a VM is definitely possible depending on which hyper-visor you are using. Unless you are trying to learn about a certain brand of switch/router this can be effective if you are trying to learn how to create a firewall that can run on a VM (pfsense for example).
If you can't emulate a particular model of switch (or run it's OS in a VM) you could use one to connect two NIC's that are mapped to different VM's on the same host.
iSCSI can be done with VM's, again it largely depends on the Hyper-Visor and guests but since it runs on Ethernet isn't too difficult to set up. Virtual Fibre Channel is also possible with some Hyper-Visors.
Probably best for you to concentrate on a single area first, think about what it is you want to learn and which OS's you would need to use. Some Hyper-Visors are fine for learning with and simpler to pick up, but might not be the most widely used in Production Environments.
IDK what kind of virtual lab are to trying to build (commercially/business or experiments) But if your going down the experiments route then any old computer will do as long as it has the ram and SSD (depending) and at least quad core. For example I bought a crappy HP laptop for 170 on black friday 2016 and I had a quad core AMD and a 5400rpm hard drive and 4GB of ram I slapped a Samsung ssd and 8gb of ram and a version of windows with hyper on it and bam I got my self a test lab. Works great with, especially with windows server labs because the integration with hyper is great and if you have a ssd that means its even faster/better. As for hyper visors I prefer hyper for experiments and esxi for the real world.
So one suggestion I have is to get your hands some inexpensive, second hand NUCs that have hardware support for VT-x (most modern intel CPUs do). They sip power and make great homelabs. If you have access to a license, ESXi is a good place to start, and has great documentation for running on a NUC in a homelab. The community surrounding ESXi is typically great at documenting specific configurations you might find yourself experimenting with at home. I personally prefer XenServer. One feature that stands out in XenServer is easy button VGA passthough. This allows you to setup a VM with hardware level access to PCIe GPU for 3D accelerated applications, similarly to Remote FX capabilities built into Hyper-V, but different in the respect that XenServer does not pool passthough GPU resources for distribution across multiple VMs as Hyper-V does.