Tape is a nice option, but it makes sense if you need to backup a lot of data. I personally have a local NAS, which is used as a backup target, and another one for offsite. You will need a library, tape drives, SAS HBAs. You should plan first and then buy all the equipment you need, As mentioned, you might consider m-disc as an alternative. In case you want to play with Tape, you can test Starwinds VTL. https://www.starwindsoftware.com/starwind-virtual-tape-library
I prefer using separate subnets for different network adapters. In any case, create vswitch and vmkernel for each network port and configure IPs.