I'm planning on installing OpenSolaris on my home server (right now it has Linux) and I would like to know how to prepare for upgrading the server to have larger hard drives in the future. Now the server has 4x 400GB SATA drives and I would install OpenSolaris with ZFS RAID-Z on them. Some time later this or next year I'm going to upgrade the drives to maybe 4x 1TB SATA drives.
How can I do the upgrading and increasing of the partition size with ZFS? Is it a simple and painless operation (e.g. replace one drive at a time and ZFS will automatically resize itself to use the full space), or are some special steps required? Can it be done without shutting down the system?