By Jeff Victor on Apr 03, 2007
Here is Yet Another Creative Use of Zones:
Overcoming some obstacles that developers face when using Solaris Containers (aka Zones), Doug Scott documented a method of building a zone which will never be patched from the global zone. In other words, when a patch is applied to the global zone, it will not be applied to a zone built using this method, even if the patch is for a package which is marked ALLZONES=true.
Normally, a package with that parameter setting will require that the package be installed in all zones, and patched consistently in all zones. Branded zones, also called 'non-native zones,' are exempt from that rule. Branded zones allow you to create a zone which will run applications meant for another operating system or operating system version. The first official brand is 'lx'. An lx-branded zone can run most Linux applications.
Note that this method would not be supported by Sun for the following reasons:
- It uses the BrandZ framework, which is available via OpenSolaris, but not yet supported by Sun.
- It requires you to edit system files which you shouldn't edit; the syntax of those files can change.
- Eventually, a patch will modify the kernel and libc (or other kernel-dependent libs) in such a way that they will be incompatible with the cbe-branded zone. Some patches must be applied manually to keep this cbe-branded zone synchronized with the global zone.
Also, note that a zone built like that will no longer benefit from one of the key advantages of zones: management simplicity. You must figure out which patches must be applied to a cbe-branded zone.
However, if those don't bother you, or if you want to learn more about how zones really work, take a look: http://www.opensolaris.org/os/project/xfce/building_xfce/brandzbuild/