In light of my recent entries, people might wonder how we've fared with operating systems here and which specific OSes have succeeded or failed. The necessary disclaimer is that this is all from my personal perspective; my co-workers might have a somewhat different view of things.

OSes that we've actively done things with while I've been here:

• OpenBSD: clear success within its domain.

  OpenBSD is our automatic choice for anything to do with firewalls (PF just works) and pretty much the default choice for related networking things like VPN servers, routers, and so on. We have a number of OpenBSD machines running additional simple network-related services and they just go and go without problems.

• Ubuntu LTS: a success but I'm not enchanted with it.

  Ubuntu LTS is our default Linux and thus our default Unix. Its combination of a long 'support' period and a wide vendor-supplied package collection continue to be unmatched (and be what we need), but it has various flaws and rough edges that leave me not really happy with it. Ubuntu LTS is more something that I put up with than something I actually like.

• Solaris: failed, as discussed.

  (We continue to build new fileservers with Solaris to match the current ones.)

• RHEL/CentOS: failed in practice.

  The short summary is that RHEL is not enough better than Ubuntu LTS and it has worse package availability (from Red Hat; we don't entirely trust EPEL, since it's a third party source). We've used RHEL on a few servers but the minor improvements (if any) haven't really been worth running another Linux distribution; the servers could as well run Ubuntu LTS and simplify our lives. I keenly regret this because I like RHEL better than Ubuntu LTS, but I have to face reality here; it's not enough better (and it has its own issues even apart from package availability).

  Our iSCSI backends run RHEL 5 and in theory the long support period is a great advantage for this. In practice they're appliances and we never update them anyways, so it's not clear how much this matters. We might stay with RHEL or CentOS in this specific situation even if we were redoing them from scratch today, just in case.

  (We continue to build new iSCSI backends with RHEL 5 to match the current ones.)

• Windows: TILT. Not applicable in our environment.

  We have one Windows terminal server for a specific, narrow purpose; to give our non-Windows users a way to run Windows programs (especially the Office suite). There's no interest in using Windows servers for anything else; as far as servers go, we're a Unix shop.

Worth mentioning:

• FreeBSD: never been seriously considered, would likely fail.

  I don't think we've ever seriously looked at running FreeBSD based servers. FreeBSD kind of fall into the 'RHEL zone', where it's different but without any solidly compelling advantage we've thought of. I've used FreeBSD enough in another environment to feel that it's nothing particularly special as Unixes go.

  It's possible that we'll wind up using FreeBSD as our next generation ZFS platform, but even then I don't think it would spread beyond that unless it turns out to be unbelievably cool.

  (In general, unless Linux somehow gets real native ZFS support I expect that any next generation ZFS platform would end up like Solaris is for us today, ie used as a special purpose appliance and no more. The most I'm hoping for is that the next generation platform is more pleasant than our current Solaris one.)

OSes that were pretty much before my time here:

• Debian: failed due to being supplanted by Ubuntu LTS.

  The problem with Debian in practice is that the support period is too short unless Debian does releases only very slowly. Beyond that, my impression is that Debian wound up being considered an inferior version of Ubuntu LTS; the few Debian based servers we used to have were replaced with ones based on Ubuntu LTS when we focused on the latter.

  (I actually built a Debian-based server here at one point (before we focused on Ubuntu LTS) but it never made it into production.)

• Red Hat Linux (now Fedora): failed, I believe in part because the support period is too short. Supplanted by Ubuntu LTS.

I don't think we've ever really looked at other Linux distributions; in general it seems unlikely that they have enough of an advantage over Ubuntu LTS to be attractive.

None of the other commercial Unixes are even on the radar (nor any of the other *BSDs; if we're not considering FreeBSD, they're even further down the list). Mac OS X is not something we run on servers, although we have some Macs and Windows machines around as test clients (since our users need our services to work with both).