Three Conductors and Twenty-five Sacks of Mail
By comay on Sep 12, 2005
I would like to thank everyone that came out to the Silicon Valley OpenSolaris Users Group (SVOSUG) meeting on August 31st and for bearing with me as we struggled with getting the laptop and projector to play nice with one another. The slides for the presentation are now available.
The questions and feedback on Zones were excellent and it was great to see the level of interest in OpenSolaris. Special thanks to Dan and Allan of the Zones project team for taking notes and lending support and of course, to the other Alan for all his work in organizing the meetings.
One frequently asked question which came up at the meeting is how can a zone support a writable directory under /usr, such as /usr/local, when the former is usually mounted read-only from the global zone.
The easiest way to support such a directory is to add a lofs(7FS) file system for the zone using zonecfg(1M). One simply needs to specify a directory in the global zone to serve as backing store for the zone's /usr/local directory and then edit the zone's configuration as follows:
global# mkdir -p /usr/local global# mkdir -p /path/to/some/storage/local/twilight global# zonecfg -z twilight zonecfg:twilight> add fs zonecfg:twilight:fs> set dir=/usr/local zonecfg:twilight:fs> set special=/path/to/some/storage/local/twilight zonecfg:twilight:fs> set type=lofs zonecfg:twilight:fs> end zonecfg:twilight> commit zonecfg:twilight> exit global#
The next time the zone boots, it will have its own writable /usr/local directory.
Speaking of frequently asked questions, Jeff has compiled a Zones and Containers FAQ which provides a list of the common questions that have been asked since Zones were introduced along with their answers. The FAQ along with a great deal of other information can also be found on the redesigned OpenSolaris Zones Community page, which was recently given a well needed makeover by Dan.