So, in previous posts, I've talked about the fact that SoylentNews currently is powered on Ubuntu 14.04 + a single CentOS 6 box. Right now, the sysops have been somewhat deadlocked on what we should do going forward for our underlying operating system, and I am hoping to get community advice. Right now, the "obvious" choice of what to do is simply do-release-upgrade to Ubuntu 16.04. We've done in-place upgrades before without major issue, and I'm relatively certain we could upgrade without breaking the world. However, from my personal experience, 16.04 introduces systemd support into the stack and is not easily removable. Furthermore, at least in my personal experience, working with journalctl and such has caused me considerable headaches which I detailed in a comment awhile ago.
Discounting systemd itself, I've also found that Ubuntu 16.04 seems less "polished", for want of a better word. I've found I've had to do considerably more fiddling and tweaking to get it to work as a server distro than I had to do with previous releases, as well as had weird issues with LDAP. The same was also true when I worked with recent versions with Debian. As such, there's been a general feeling with the sysops that it's time to go somewhere else.
Below the fold are basically the options as we see them, and I hope if the community can provide some interesting insight or guidance.
Right now, we have about three years before security updates for 14.04 stop, and we are absolutely forced to migrate or upgrade. However, we're already hitting pain due to outdated software; I managed to briefly hose the DNS setup over the weekend trying to deploy CAA records for SN due to our version of BIND being outdated. When TLS 1.3 gets standardized, we're going to have a similar problem with our frontend load balancers. As such, I want to get a plan in place for migration so we can start upgrading over the next year instead of panicking and having to do something at the last moment
As with any discussion for server operating system, knowing what our workloads and such is an important consideration. In short, this is what we use for SN, and the software we have to support
In addition, we use mandatory application controls (AppArmor) to limit the amount of stuff a given process can access for critical services to try and help harden security. We'd like to maintain support for this feature to whatever we migrate, either continuing with AppArmor, switching to SELinux, or using jails/zones if we switch operating systems entirely.
Right now, we've floated a few options, but we're willing to hear more.
The first choice is simply migrate over to a distribution where systemd is not present or completely optional. As of writing, Arch Linux, Gentoo, and Slackware are three such options. Our requirements for a Linux distribution is a good record of updates and security support as I don't wish to be upgrading the system once a week to a new release.
I'm aware of the Devuan project, and at first glance, it would seem like an obvious choice; Debian without systemd is the de-facto tagline. However, I've got concerns about the long-term suitability of the distribution, as well as an intentional choice to replace much of the time-tested Debian infrastructure such as the testing archive with a git-powered Jenkins instance in it's place. Another option would be slackware, but Slackware has made no indication that they won't adapt systemd, and is historically very weak with in-place upgrading and package management in general. Most of the other distributions on without-systemd.org are either LiveCDs, or are very small minority distros that I would be hesitant to bet the farm on with.
On the other side of the coin, and an option favored by at least some of the staff is to migrate to Gentoo or Arch, which are rolling-release. For those unaware, a rolling release distribution basically always has the latest version of everything. Security updates are handled simply by updating to the latest upstream package for the most part. I'm not a huge fan of this option, as we're dependent on self-built software, and it's not unheard of for "emerge world" to break things during upgrades due to feature changes and such. It would essentially require us to manually be checking release notes, and crossing our fingers every time we did a major upgrade. We could reduce some of this pain by simply migrating all our infrastructure to the form of ebuilds so that at least they would get rebuild as part of upgrading, but I'm very very hesitant about this option as a whole, especially for multiple machines.
Another way we could handle the problem is simply jump off the Linux ship entirely. From a personal perspective, I'm not exactly thrilled on the way Linux as a collective whole has gone for several years, and I see the situation only getting worse with time. As an additional benefit, switching off Linux gives us the possiblity of using real containers and ZFS, which would allow us to further isolate components of the stack, and give us the option to do rollbacks if ever necessary on a blocked upgrade; something that is difficult to impossible with most Linux distributions. As such, I've been favoring this option personally, though I'm not sold enough to make the jump. Two major options attract me of these two:
FreeBSD has been around a long time, and has both considerable developer support, and support for a lot of features we'd like such as ZFS, jails, and a sane upstream. FreeBSD is split into two components, the core stack which is what constitutes a release, and the ports collection which is add-on software. Both can be upgraded (somewhat) independently of each other, so we won't have as much pain with outdated server components. We'd also have the ability to easy create jails for things like rehash, MySQL, and such and easily isolate these components from each other in a way that's more iron-clad than AppArmor or SELinux.
illumos is descended from OpenSolaris, and forked after Oracle closed up the source code for Solaris 11. Development has continued on it (at a, granted, slower place). Being the originator of ZFS, it has class A support for it, as well as zones which are functionally equivalent to FreeBSD jails. illumos also has support for SMF, which is essentially advanced service management and tracking without all the baggage systemd creates and tendrils throughout the stack. Zones can also be branded to run Linux binaries to some extent so we can handle migrating the core system over by simply installing illumos, restoring a backup into a branded zone, and then piecemeal decommissioning of said zone. As such, as an upgrade choice, this is fairly attractive. If we migrate to illumos, we'll either use the SmartOS distribution, or OpenIndiana.
Right now, we're basically on the fence with all options, so hopefully the community can provide their own input, or suggest other options we're not aware of. I look forward to your comments below!
~ NCommander
(Score: 5, Insightful) by RedBear on Tuesday February 07 2017, @05:56PM
I've played around with a lot of non-Windows operating systems over the past 25 years. From that experience and research into all operating system platforms, I have trouble understanding why there is even a question of which direction to go with something like a server running a database-driven website. Linux may have "more stable" flavors available, but anyone who has paid any attention to the evolution of Linux should have noticed that it has spent its entire life (a quarter century now) being semi-experimental and bleeding edge. Great for people who like to tinker and get support for the latest desktop hardware and people playing with making Beowulf clusters. And now there is the Great SystemD Split, causing at least a third of even long-time Linux fans to see Linux as having lost the plot.
On the other hand, there is a community that has spent the last 30 or more years, in a very general sense, concentrating entirely on having a culture of long-term stability both in the community ideals and guiding principles, and in the software development. A community that has never spent much time and effort trying to be bleeding edge but rather on creating solid, stable, efficient code bases for many of the most important servers that need to remain stable for years while getting hammered with unimaginable amounts of traffic on the Internet. Of course this is the BSD community. Extremely impressive and popular security software such as OpenSSH and PF emanated from the OpenBSD community. Skills you may have learned using a BSD distribution 30 years ago are still applicable to FreeBSD today, and skills you learn today will still be applicable to FreeBSD or one of its variants 30 years from now. I have always seen the BSDs as a platform that it truly makes sense to spend the time to master if you have a real production server environment to run.
If you have enough faith to expect this site to still exist 30 years from now, I honestly don't get why there would even be a question of which direction to go. I'm sure the Solaris-based stuff is also magical and powerful, but think about the likelihood that any future volunteer maintainers will be familiar with it, and how stable the future development might be. For me, the best possible choice for this task is FreeBSD's stable branch. You lay out all the good reasons yourself in the quote above.
But, that's just my opinion, and as always I could be quite wrong.
¯\_ʕ◔.◔ʔ_/¯ LOL. I dunno. I'm just a bear.
... Peace out. Got bear stuff to do. 彡ʕ⌐■.■ʔ
(Score: 4, Informative) by TheRaven on Wednesday February 08 2017, @01:42AM
For me, the best possible choice for this task is FreeBSD's stable branch.
I hope this was a typo, and you meant release branch. The stable branch in FreeBSD is the middle branch in terms of stability. Unlike current (head) it is guaranteed to maintain a stable ABI (and KBI) over its lifetime, but it doesn't get any of the release testing - it's the branch from which the next minor stable release will be cut, after people who enjoy testing things have tested it. Please don't run it on production unless it's on an expendable machine (if you've built in fault tolerance at a higher level, please do run it on a few machines and report any issues though, because that's how we try to make sure bugs don't end up in the releases). In practice, it's probably fine, but it comes with absolutely no claims of reliability.
sudo mod me up
(Score: 2) by RedBear on Wednesday February 08 2017, @06:35AM
Ah, yes, I forgot FreeBSD has that odd naming where "stable" just means "it probably won't blow up too frequently". That's a bit of a confusing misnomer. Been too long since I've actually used FreeBSD in any meaningful way. I only meant that the most stable branch of FreeBSD should be used, obviously. Which I expect people like NCommander to already understand much better than I do.
¯\_ʕ◔.◔ʔ_/¯ LOL. I dunno. I'm just a bear.
... Peace out. Got bear stuff to do. 彡ʕ⌐■.■ʔ
(Score: 2) by TheRaven on Thursday February 09 2017, @12:00AM
Ah, yes, I forgot FreeBSD has that odd naming where "stable" just means "it probably won't blow up too frequently".
Stable doesn't mean anything about how frequently it will blow up. Stable means the ABI / KBI is stable. If you build a kernel module against any version of the stable branch, then it will work with any future version of the same stable branch. Similarly, any piece of userspace code compiled for a release of the stable branch will work with any future version of the stable branch.
sudo mod me up
(Score: 2) by RedBear on Thursday February 09 2017, @04:34AM
Somebody needs to take some things a little bit less seriously.
¯\_ʕ◔.◔ʔ_/¯ LOL. I dunno. I'm just a bear.
... Peace out. Got bear stuff to do. 彡ʕ⌐■.■ʔ