Yep, I'm a big OpenVZ guy. OpenVZ 7 just came out at the end of July. It added KVM virtual machines in addition to OpenVZ containers. That was a big change considering the commercial product OpenVZ came from (PCS - Parallels Cloud Server v6) used a proprietary hypervisor. Den Lunev, who has worked on this stuff for 15+ years (SWsoft, Parallels, and now Virtuozzo) spoke about everything that went into moving to KVM in Virtuozzo 7 / OpenVZ 7 at the KVM Forum last week. Enjoy! (PDF Slide Deck)
I recently encountered an Alpine Linux developer in the #openvz Freenode IRC channel who was working on an Alpine Linux-based LiveCD that uses the OpenVZ Legacy stable kernel and tools. If you aren't familiar with Alpine Linux (and I wasn't prior), it is a very minimal Linux distro that uses BusyBox. The LiveCD shafire (his IRC nick) created is ~ 100MB in size. Since I know OpenVZ very well, shafire asked me to lend a hand with testing.
I recorded a screencast that shows using the LiveCD from start to finish. Being very small, and needing storage space for containers, besides the LiveCD you really need a disk partition for permanent storage. The video shows booting the CD, a few manual steps that are needed to get a proper environment established, creating two containers, starting them, entering them and running some simple commands, shutting them down, and shutting down the host. I did all of the testing using a KVM virtual machine which made it easy for video capture. The video runtime is about 11 minutes and there was no editing of the video... everything is absolutely in real-time with no speedups. It is just THAT fast. :)
The embedded video is in webm/vp9 format and should play fine in contemporary versions of Firefox and Google Chrome. If you are using another browser and can't play the video, feel free to use the link under the video to download it and play with a recent version of the VLC media player. Looks like some video feeds that pick up my blog (planet.openvz.org for example) aren't embedding it properly so in that case, use the link under the video. That should work.
If you prefer to download and play in local media player, here's the direct URL:
For those interested in screencast creation and video conversion stuff, I used vokoscreen to capture my screen. It natively output a 175.9 MB .mkv file. I used ffmpeg to convert it to a webm file (vp9 video codec, no audio). The resolution is > 480p and the quality is very good... but amazingly, the filesize for the 11 minute video is only 1.7 MB. I guess ffmpeg / vp9 are awesome at comrpession of this genre of video. I set an upper limit of 200 Kbit for the video bitrate but using a variable bitrate it was able to greatly reduce the bitrate for the bulk of the video.
Odin and the OpenVZ Project announced the beta release of a new version of Virtuozzo today. This is also the next version of OpenVZ as the two are merging closer together. See their release announcement.
There will eventually be two distinct versions... a free version and a commercial version. So far as I can tell they currently call it Virtuozzo 7 but in a comparison wiki page they use the column names Virtuozzo 7 OpenVZ (V7O) and Virtuozzo 7 Commercial (V7C). The original OpenVZ, which is still considered the stable OpenVZ release at this time based on the EL6-based OpenVZ kernel, appears to be called OpenVZ Legacy.
Odin had previously released the source code to a number of the Virtuozzo tools (mailing list post) and followed that up with the release of spec-like source files used by Virtuozzo's vztt OS Template build system. The plan is to migrate away from the OpenVZ specific tools (like vzctl, vzlist, vzquota, and vzmigrate) to the Virtuozzo specific tools although there will probably be some overlap for a while.
The release includes source code, binary packages and a bare-metal distro installer DVD iso.
Bare Metal Installer
I got a chance to check out the bare-metal installer today inside of a KVM virtual machine. I must admit that I'm not very familiar with previous Virtuozzo releases but I am a semi-expert when it comes to OpenVZ. Getting used to the new system is taking some effort but will all be for the better.
I didn't make any screenshots yet of the installer... I may do that later... but it is very similar to that of RHEL7 (and clones) because it is built by and based on CloudLinux... which is based on EL7.
What is CloudLinux? CloudLinux is a company that makes a commercial multi-tenant hosting product... that appears to provide container (or container-like) isolation as well as Apache and PHP enhancements specifically for multi-tenant hosting needs. CloudLinux also offers KernelCare-based reboot-less kernel updates. CloudLinux's is definitely independent from Odin and the CloudLinux products are in no way related to Virtuozzo. Odin and CloudLinux are partners however.
Why is the distro based on CloudLinux and does one need a CloudLinux subscription to use it? Well it turns out that Odin really didn't want to put forth all of the effort and time required to produce a completely new EL7-clone. CloudLinux is already an expert at that... so Odin partnered with CloudLinux to produce a EL7-based distro for Virtuozzo 7. While CloudLinux built it and (I think) there are a few underlying CloudLinux packages, everything included is FOSS (Free and Open Source Software). It DOES NOT and WILL NOT require a CloudLinux subscription to use... because it is not related to CloudLinux's product line nor does it contain any of the CloudLinux product features.
The confusion was increased when I did a yum update post-install and if failed with a yum repo error asking me to register with CloudLinux. Turns out that is a bug in this initial release and registration is NOT needed. There is a manual fix of editing a repo file in /etc/yum.repos.ed/) and replacing the incorrect base and updates URLs with a working ones. This and and other bugs that are sure to crop up will be addressed in future iso builds which are currently slated for weekly release... as well as daily package builds and updates available via yum.
More Questions, Some Answers
So this is the first effort to merge Virtuozzo and OpenVZ together... and again... me being very Virtuozzo ignorant... there is a lot to learn. How does the new system differ from OpenVZ? What are the new features coming from Virtuozzo? I don't know if I can answer every conceivable question but I was able to publicly chat with Odin's sergeyb in the #openvz IRC channel on the Freenode IRC network. I also emailed the CloudLinux folks and got a reply back. Here's what I've been able to figure out so far.
Why CloudLinux? - I mentioned that already above, but Odin didn't want to engineer their own EL7 clone so they got CloudLinux to do it for them and it was built specifically for Virtuozzo and not related to any of the CloudLinux products... and you do not need a subscription from Odin nor CloudLinux to use it.
What virtualization does it support? - Previous Virtuozzo products supported not only containers but a proprietary virtual machine hypervisor made by Odin/Parallels. In Virtuozzo 7 (both OpenVZ and Commercial so far as I can tell) the proprietary hypervisor has been replaced with the Linux kernel built-in one... KVM. See: https://openvz.org/QEMU
How about libvirt support? - Anyone familiar with EL7's default libvirtd setup for KVM will be happy to know that it is maintained. libvirtd is running by default and the network interfaces you'd expect to be there, are. virsh and virt-manager should work as expected for KVM.
Odin has been doing some libvirt development and supposedly both virsh and virt-manager should work with VZ7 containers. They are working with upstream. libvirt has supposedly supported OpenVZ for some time but there weren't any client applications that supported OpenVZ. That is changing. See: https://openvz.org/LibVirt
Command line tools? - OpenVZ's vzctl is there as is Virtuozzo's prlctl.
How about GUIs or web-based management tools? - That seems to be unclear at this time. I believe V7C will offer web-based management but I'm not sure about V7O. As mentioned in the previous question, virt-manager... which is a GUI management tool... should be usable for both containers and KVM VMs. virsh / virt-manager VZ7 container support remains to be seen but it is definitely on the roadmap.
Any other new features? - Supposedly VZ7 has a fourth-generation resource management system that I don't know much about yet. Other than the most obvious stuff (EL7-based kernel, KVM, libvirt support, Virtuozzo tools, etc), I haven't had time to absorb much yet so unfortunately I can't speak to many of the new features. I'm sure there are tons.
About OS Templates
I created a CentOS 6 container on the new system... and rather than downloading a pre-created OS Template that is a big .tar.gz file (as with OpenVZ Legacy) it downloaded individual rpm packages. It appears to build OS Templates on demand from current packages on-demand BUT it uses a caching system whereby it will hold on to previously downloaded packages in a cache directory somewhere under /vz/template/. If the desired OS Template doesn't exist already in /vz/template/cache/ the required packages are downloaded, a temporary ploop image made, the packages installed, and then the ploop disk image is compressed and added to /vz/template/cache as a pre-created OS Template. So the end result for my CentOS 6 container created /vz/template/cache/centos-6-x86_64.plain.ploopv2.tar.lz4. I manually downloaded an OpenVZ Legacy OS Template and placed it in /vz/template/cache but it was ignored so at this time, I do not think they are compatible / usable.
The only OS Template available at time of writing was CentOS 6 but I assume they'll eventually have all of the various Linux distros available as in the past... both rpm and deb based ones. We'll just have to wait and see.
As previously mentioned, Odin has already released the source code to vztt (Virtuozzo's OS Template build system) as well as some source files for CentOS, Debian and Ubuntu template creation. They have also admitted that coming from closed source, vztt is a bit over-complicated and not easy-to-use. They plan on changing that ASAP but help from the community would definitely be appreciated.
How about KVM VMs?
I'm currently on vacation and only have access to a laptop running Fedora 22... that I'm typing this from... and didn't want to nuke it... so I installed the bare-metal distro inside of a KVM virtual machine. I didn't really want to try nested KVM. That would definitely not have been a legitimate test of the new system... but I expect libvirtd, virsh, and virt-manager to work and behave as expected.
Despite the lack of perfection in this initial release Virtuozzo 7 shows a lot of promise. While it is a bit jarring coming from OpenVZ Legacy... with all of the changes... the new features... especially KVM... really show promise and I'll be watching all of the updates as they happen. There certainly is a lot of work left to do but this is definitely a good start.
I'd love to hear from other users to find out what experiences they have.
Congrats Odin and OpenVZ! I only wish I had a glass of champagne and could offer up a respectable toast... and that there were others around me to clank glasses with. :)
If you didn't notice, Fedora 22 was released today. Today I refreshed the Fedora 22 OS Template I made for OpenVZ and uploaded it to contrib. For fun, I thought I'd build a MATE Desktop GUI container right in front of your eyes... and then connect to it via x2go.
Installing a desktop environment in a container can be fraught with danger for the uninitiated. The problem? Well, it always drags in NetworkManager, a graphical login manager, and various other packages / services that aren't really appropriate for a container. With a handful of systemd statements though, it is an easy fix. Watch and I'll show you how. Enjoy!
For those with iFrame issues, here's a direct link to the webm video:
You can pretty much use the same recipe for other desktop environments. The only thing you want to avoid are desktop environments that require accelerated 3D because those won't work over x2go. Which desktops use that? GNOME and Plasma 5... Cinnamon probably... and if you were on Ubuntu, Unity. XFCE, MATE, OpenBox, LXQT, etc work fine... although I haven't tried them all.