Mirror Upgrade - Step by Step, the Right Way

The last time I tried to upgrade the mirror I messed up.  I ended up with the following:

Disk	Size (MB)	Description	Device model	Virtual device	Pool
da0	1907730	Seagate Barracuda Green (AF)	ST2000DL003-9VT166	tank_mirror_0	tank
da1	1907730	Seagate Barracuda Green (AF)	ST2000DL003-9VT166
da2	2861589	Seagate Barracuda 7200.14 (AF)	ST3000DM001-1E6166	vault_mirror_1	vault
da3	2861589	Seagate Barracuda 7200.14 (AF)	ST3000DM001-1E6166
da4	3815448	Seagate NAS HD	ST4000VN000-1H4168	vault_disk_2
da5	3815448	WD Red	WDC WD40EFRX-68WT0N0	VeryTemp	VeryTemp

da4 ended up being added in serial not in parallel fashion.  I then added da5 and copied the content of the pool vault to it.  I am about to add another drive in parallel with da5 (thus making VeryTemp a mirror) and remove da2, da3 and da4.


Here is what I did step-by-step:

• Power NAS down
• Remove 3 disks da2, da3 and da4.  Do not erase anything in case something goes wrong with this procedure.
• Install new WD Red.
• Diagnostics\Information\Disks - now has new drive!
• Disks\Management - Clear Config and Import disks
• Change for every disk:
  Description - Western Digital Red
  Hard disk standby time - 30min
  APM - 127
  Acoustic level - disabled
  SMART - activated
• Disks\Format - new disk unavailable ;-(
  restart
• Disks\Format - new disk unavailable ;-(
• Disks\ZFS\Pools\Management - remove old pool
• Disks\ZFS\Configuration - Synch
• Disks\Format - new disk available!
      File System - ZFS, no option for 4K sectors - should I be woried?
• Disks\ZFS\Pools\Tools
   attach device VeryTemp da2 da3
• Disks\ZFS\Pools\Information - you can see resilvering in process!
• Finally rename the pool VeryTemp to vault - this is the only step which requires access to command line:
zpool export VeryTemp
zpool import VeryTemp vault

And here is what I ended up with:

Disk	Size (MB)	Description	Device model	RPM	Virtual device	Pool
da0	1907730	Seagate Barracuda Green	ST2000DL003-9VT166	5900	tank_mirror_0	tank
da1	1907730	Seagate Barracuda Green	ST2000DL003-9VT166	5900
da2	3815448	Western Digital Red	WDC WD40EFRX-68WT0N0	5400	vault_mirror_1	vault
da3	3815448	Western Digital Red	WDC WD40EFRX-68WT0N0	5400

Dada!
Isn't ZFS awesome for its ability to reconfigure things on the fly?