Andrew Lentvorski wrote: > Gus Wirth wrote: >> I think what you want is VMware. Do all your computing in a virtual >> machine and when you break something roll back to the last known good >> snapshot. You can keep lots of snapshots and even branch them for >> different tasks. > > OpenSolaris also has a nice feature which takes a ZFS snapshot of your > system before upgrading, upgrades it, and then switches over to the new > system. You can revert back to the old snapshot, however, if you want. >
How expensive are these snapshots -- are they COW? Presumably you need to quiesce the fs (and things like databases) before the snapshot, eh? If so, is that much of a burden? Anybody got a real life feel for these things? I assume VMware snapshots are a different animal -- do their snapshots require a restart, maybe? I remember that lvm snapshots had noticeable performance costs for multiple snapshots -- and at the time I was messing with it (~3 years ago), there were some nasty bugs (quiesce didn't work or hung, memory allocation problems) that crashed stuff! Haven't kept up so I have no idea about current versions. Regards, ..jim -- [email protected] http://www.kernel-panic.org/cgi-bin/mailman/listinfo/kplug-list
