2024-07-28
Our slowly growing Unix monoculture
Once upon a time, we ran Ubuntu Linux machines, OpenBSD machines, x86 Solaris machines, and what was then RHEL machines (in the days of our first generation ZFS fileservers). Over time, Solaris changed to OmniOS (and RHEL to CentOS), but even at the time it was clear that both of those hadn't caught on here and after a while we replaced the OmniOS fileservers and CentOS iSCSI backends with our third generation Ubuntu-based fileservers. Then recently, the final pieces of CentOS have been getting removed, such as our central syslog servers because CentOS as it originally was is dead (the current 'CentOS Stream' doesn't meet our needs).
Our OpenBSD usage has also been dwindling. Originally we used OpenBSD for firewalls, most DNS service, a DHCP server, and several VPN servers (for different VPN protocols). Our internal DNS resolvers now run Bind on Ubuntu and we've been expecting to some day have to move our VPN servers away from OpenBSD in order to get more up to date versions of the various VPNs (although this hasn't happened yet). The OpenBSD DHCP server is fine so far, but we have three DHCP servers and two of them are Ubuntu machines, so I wouldn't be surprised if we switch the third to Ubuntu as well when we next rebuild it.
(There's basically no prospect of us switching away from OpenBSD on the firewalls, but the firewalls are effectively appliances.)
It's probably been plural decades since our users logged in to anything other than x86 Ubuntu machines, and at least a decade since any of them were 32-bit x86 instead of 64-bit x86. It seems unlikely that we'll get ARM-based machines, especially ones that we expose to people to log in to and use. I expect we'll have to switch away from Ubuntu someday, but that will be a switch, not a long term plan of running Ubuntu as well as something else, and the most likely candidate (Debian) won't look particularly different to most people.
The old multi-Unix, multi-architecture days had their significant drawbacks, but sometimes I wonder what we're losing by increasingly becoming a monoculture that runs Ubuntu Linux and (almost) nothing else. I feel that as system administrators, there's something we gain by having exposure to different Unixes that make different choices and have different tools than Ubuntu Linux. To put it one way, I think we get a wider perspective and wind up with more ideas and approaches in our mental toolkit. We have that today because of our history, so hopefully it won't atrophy too badly when we really narrow down to being a monoculture.