German railway seeks IT admin to manage MS-DOS and Windows 3.11 systems

[Ben Myers]

DOS/3.1 has a perfect advantage over later operating systems. It's naturally air gapped and has very few security concerns not having internet access. And IMHO that's really your biggest concern with a infrastructure system, keeping the system secure. It's easy enough to plan for maintenance down time if your smart about it.

DOS 6.1 is even better. And do not forget various DOS extensions like LFNs and the entire FreeDOS.