Zones will change Solaris forever

Of all the new features planned for Solaris 10, I think zones (sometimes called “N1 Grid Containers” in Sun’s marketing literature) will see the most widespread, rapid adoption early on in the release cycle. In fact, some people are already moving to Solaris 10 via the Solaris Express program, perhaps a full *year* ahead of it’s general release, just to get zones. They’re that powerful. To understand just how revolutionary zones will be for Solaris sysadmins, all you need to do is read Dennis Clarke’s intro, Get in the Zone.

The first thing I’ve used zones for is to provide remote collaborator access at the GSC. Each collaborator gets a zone which they can FTP/SCP into to retrieve data, get a shell to run our tools, submit jobs to the cluster, and so on. From the global zone I can place all sort of wonderful resource limits on a per-zone basis, including seperate IP Filter rules to restrict network access, CPU and memory limits, and of course I can quickly and easily shutdown/startup zones as collaborators come and go.

The next logical step is to implement each “service” inside a zone. Got a bunch of convoluted apache configurations with different modules and dependencies that won’t play nicely together on one server? Don’t want to buy dedicated servers for each scripting/app server technology? Just bring up different apache instances inside isolated zones. Run one “master” apache zone if you want that just proxy_rewrite’s different URLs and file types (.php, .html, .pl, etc.) to special-purpose apaches in each zone transparently. Need to update to the latest PHP? No problem. Just bring up a test zone, and when it’s configured properly swap it in for the current PHP zone.

Combine “service zones” with, say, a reliable central NFS server for the zone roots, and you’ve got a brilliant way to move big complex service installations from machine to machine in a snap. Buy one hot-backup server to serve as a standby for a dozen different zones running on half a dozen different servers. Server fails? Just bring up its zones on the standby. Need a faster box? No problem, just pop it in, stop the zone on the old box and bring it up on the new box.

The possibilities are endless. Sysadmins are going to love zones.