• Perform a system upgrade in a jail(8)
Create a new boot environment called jailed:
beadm create -e default jailed
Set mountpoint for new jail to /usr/jails/jailed:
beadm mount jailed /usr/jails/jailed
The currently active boot environment is now replicated into the
jailed system and ready for upgrade. Startup the jail, login and
perform the normal upgrade process. Once this is done, stop the jail
and disable it in /etc/rc.conf.
Now activate the boot environment for the next boot
beadm activate jailed
Reboot into the new environment
A HOWTO guide is posted at the FreeBSD forums:
For the record: I don't fully agree with Oko on this point but I do think he raises a fair concern...Why's that?
on a 32bit system 4GB is the theoretical maximum amount of memory you can address. In reality this number lies much lower. Add 4GB of memory to a 32bit system and you most likely only got 2 - 2.5GB at your disposal.