SOLVED Hard Drive In RAIDZ2 - Pool Upgrade /Bad HDD Replacement

[NASbox]

I'm hoping one of the ZFS ninjas on this board can help me with the following questions:

I've got a ZPOOL with 4 x 3TB Seagate drives (lousy drives, but at the time there was no reasonably priced alternative). One of the drives is showing a few bad sectors, so I want to replace it. I was thinking about upgrading the pool to 4 x 6TB WD Red drives. My questions are:

1. Can I increase the size of the pool by swapping the drives 1 at a time and letting the pool re-silver?
2. What is the impact on the pool of only replacing 1 drive? Does this do any harm/degrade the pool?
(Is my understanding correct that: the pool will use the drive, but limit it to the size of the other drives - i.e.3TB)? I was thinking of replacing the drives 1/month for both cash flow reasons and also giving me time to find out how the WD Red drives perform (and make sure I have drives from different batches to decrease the odds of multiple simultaneous failures). Any problem with this strategy?

Thanks in advance for any help you can provide.

 

[SweetAndLow]

You are correct on your assumptions and you replacing strategy seems good.

 

[Ericloewe]

Just make sure your backups are in working order and all original drives are in good health, since you'll be in a degraded state each time you swap drives.

And follow the manual to the letter - FreeNAS can be slightly unintuitive at times.

 

[NASbox]

Thanks that helps to know I'm on the right track... I've done a replacement before when I first built the box. I loaded the pool up with junk, took a disk out, wiped GPT and resilvered just to see how things worked.

 

[SirMaster]

Just make sure your backups are in working order and all original drives are in good health, since you'll be in a degraded state each time you swap drives.

And follow the manual to the letter - FreeNAS can be slightly unintuitive at times.

Apparently the FreeNAS GUI does allow for swapping/replacing disks without ever taking the zpool into a DEGRADED state.

https://forums.freenas.org/index.ph...-without-losing-redundancy.24724/#post-153906