Score:0

change ZFS mirrored drive set to SMALLER drives

cn flag

I have a ZFS mirror setup and one of the drives has failed completely. These are WD reds at 4tb. This drive set has had much of its content moved and is much smaller and I do NOT need the space there. This complicated by my home directory and virtual box systems defined there - but no other data. I am using less then 500gb now. I have previously removed a 2tb mirror with older enterprise/golds. I would like to replace the bad 4tb with a good 2tb gold drive, resilver the drive - then replace the OTHER WD Red with the other 2tb gold - reducing the mirror set from 4tb to 2tb. Is this even possible without losing my home directory?

Score:0
cn flag

You could create a new pool with the smaller drive and then zfs send/zfs receive the original pool into it. When that is complete, take the original pool offline and move the new pool into its place. Finally, add a second smaller drive to the new smaller mirror.

This is fairly low risk because you will always have the other large drive available if there is an error building the mirror on the smaller array. I have done this many times and it works well, always nerve-racking until the new drive has all the data if you only have one drive in the original mirror.

Note: Swapping the pools can be done using another user with a home directory which is not on the pool, the swap can be performed quickly so your pms and user won't be offline for very long.

cn flag
all home directories are on the drive/pool that I want to replace.
cn flag
additional complications - all my virtual machines are defined on that disk as well - this is a headless machine and if my virtual machines don't run - I cannot connect - at least easily - needing a monitor/keyboard/mouse - at the actual machine - not simple
SEWTGIYWTKHNTDS avatar
cn flag
So you cannot ssh into the vm host machine at all?
cn flag
I can ONLY SSH into the host machine from my local network - remote is where I usually connect. I might just get a WD red to replace my bad one, resilver into the mirror and work on the migration of home directories at another time.
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