[Users] HA: Show stopper while trying out Openvz 7 beta 1

Scott Dowdle dowdle at montanalinux.org
Tue Aug 4 08:11:55 PDT 2015


Greetings,

----- Original Message -----
> You don’t need to download ez-template before caching – vzctl/vzpkg
> could do that job. Note also that if your node has an internet
> access and standard repositories configured:
> 
> vzpkg list –O –available
> will display list of available EZ OS templates.

Just to clarify...

There are some "meta-data" packages (from the package manager repos).  They have ez in the name.  So for example:

#  rpm -qa | grep ez | grep -v bluez | sort
centos-5-x86-ez-7.0.0-2.vz7.noarch
centos-6-x86_64-ez-7.0.0-1.vz7.noarch
centos-7-x86_64-ez-7.0.0-5.vz7.noarch
debian-8.0-x86_64-ez-7.0.0-2.vz7.noarch
ubuntu-14.04-x86_64-ez-7.0.0-2.vz7.noarch

I filtered out bluez because there was one stock distro package that was unrelated that matched named bluez-libs.  Anyway... those packages are OS Template meta-data packages that define what the OS Template is, what packages it should contain, what the URLs are for the packages, etc.

By default on the most recent bare-metal installer I believe all of the centos meta-data packages are pre-installed.  The debian and ubuntu meta-data packages are not... so if you want to make those containers, you should probably:

yum install debian-8.0-x86_64-ez-7.0.0-2.vz7.noarch ubuntu-14.04-x86_64-ez-7.0.0-2.vz7.noarch

With all of those "ez" packages installed, vzpkg can do its thing and assemble OS Templates and cache them.  And you can refresh them whenever you want so you can keep your OS Templates current with all of the updates.  In the past, the OpenVZ Project built a lot of OS Templates and updated them every 3 months or so.  Now with the ez packages you can build them whenever you want and update them yourself.  Again, in the early days of OpenVZ, it was very similar.

Now the question remains... will the pool of ez meta-data packages continue to grow?  Will we get ez meta-data packages for Fedora, openSUSE, and others?

The format of the OS Template seems to have changed as the end result of a OS Template construction has the following naming convention:

# ls -lh /vz/template/cache/
total 1.2G
-rw-r--r-- 1 root root 337M Jul 28 10:59 centos-6-x86_64.plain.ploopv2.tar.lz4
-rw------- 1 root root    0 Jul 28 10:54 centos-6-x86_64.plain.ploopv2.tar.lz4.lock
-rw-r--r-- 1 root root 291M Jul 27 17:32 centos-7-x86_64.plain.ploopv2.tar.lz4
-rw------- 1 root root    0 Jul 27 17:30 centos-7-x86_64.plain.ploopv2.tar.lz4.lock
-rw-r--r-- 1 root root 312M Jul 28 14:59 debian-8.0-x86_64.plain.ploopv2.tar.lz4
-rw------- 1 root root    0 Jul 28 14:39 debian-8.0-x86_64.plain.ploopv2.tar.lz4.lock
-rw-r--r-- 1 root root 237M Jul 28 16:51 ubuntu-14.04-x86_64.plain.ploopv2.tar.lz4
-rw------- 1 root root    0 Jul 28 16:45 ubuntu-14.04-x86_64.plain.ploopv2.tar.lz4.lock

I wonder what is meant by "plain" and ploopv2?  Is the flavor of ploop different between OpenVZ Legacy and V7?

OpenVZ Legacy has ploop-1.13.2-1.x86_64
V7 has ploop-7.0.10-1.vz7.x86_64

lz4 is used rather than gz or xz.

OpenVZ Legacy OS Templates contain a big directory structure but V7's OS Templates have ploop disk images in them.

We understand that containers and their filesystems from OpenVZ Legacy aren't compatible with V7... and they must undergo some conversion process.  Could we see some examples of that?  I think I sorta saw some mention in an openvz-devel mailing list post but the vast majority of that stuff is over my head so I haven't paid that much attention.

Anyway, it would be nice to figure out how to make a blank OS Template disk image on a V7 host, mount it, and then rsync into it the contents of any one of the many OpenVZ Legacy OS Templates that currently aren't available for V7.  While that might be sloppy... and multi-step... it at least expands the pool and helps us better understand how the underlying components work... and opens the door to contributed OS Templates.  Ideally though, the number of ez meta-data packages will grow but given the current complexity of vztt and the ez meta-data packaging... I see much less potential for contributed ez OS Templates.

TYL,
-- 
Scott Dowdle
704 Church Street
Belgrade, MT 59714
(406)388-0827 [home]
(406)994-3931 [work]



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