[gentoo-user] Re: Problem with detecting ZFS HDD

[gevisz <gevisz@gmail.com>]

The small correction: the penultimate sentence
of my previous email should read:
"The situation remained the same even after swapping the
undetected 500GB WD HDD with the spare one."

чт, 30 янв. 2025 г. в 18:55, gevisz <gevisz@gmail.com>:
>
> About half a year ago my old 1.5TB SATA Green WD HDD
> tapped me on the shoulder and said: "Hi, very soon you won't
> be able to read any data from me."
>
> As I have not made my backups regularly, I took this warning
> seriously and decided to finally realize my old idea of moving
> from ext4 to ZFS.
>
> So, I have bought a 500GB SATA Green WD HDD.
> Based on its price, I suspected it was refurbished,
> but I didn't have much choice since the Green WD HDDs
> were apparently no longer in production, and
> the 2TB Gold WD HDD was incomparably more expensive.
>
> After installing ZFS on it, it turned out that everything works well.
> So, I decided to buy two other WD HDD of the same model,
> to set one of them as a ZFS mirror and leave the third WD HDD
> for the time when one of its twin brothers fails.
>
> This time the seller warned me that these WD HDDs
> are refurbished but assured me that they were refurbished
> by WD itself. Taking into account that the previous such HDD
> behaved quite well, I decided to proceed with my purchase.
>
> After setting up one of them as a ZFS mirror, I immediately
> got the problem that if I boot my system with additional HDD
> connected to my computer, one of these ZFS mirror disks
> is not detected and the corresponding zpool appears to be degraded.
>
> I have realized that it was my fault to use /dev/sdb and /dev/sdc
> notations when setting up the ZFS mirror because with more disks
> at the boot time these notations may change.
>
> I should have used /dev/disk/by-id/ata-WDC_WD5000* notations instead!
>
> Unfortunately, I have not found the way to change these notations
> other than deleting the whole zpool and re-creating it anew with
> the notations /dev/disk/by-id/ata-WDC_WD5000*, which took quite
> a lot of time.
>
> Presumably, the problem with detecting my ZFS mirror HDDs
> should have disappeared after that because now the disks were
> referred to by their ids but unfortunately it was not the case.
>
> When I boot my computer with an additional external HDD
> attached to the computer via USB, one of my ZFS mirror HDDs
> is not detected by the system and the corresponding zpool again
> appears to be degraded until I restart my computer in the usual
> setup, that is, without any additional HDD attached to it.
>
> I have looked into my /dev/disk/by-id/ directory and found out
> that this happens because one of these ZFS mirror HDDs
> does not appear in this directory at all!
>
> The situation remained the same even after swapping the
> undetected 500GB WD HDD with the spare one.
>
> So, I wonder if it is a fault of
> 1) refurbished WD HDDs
> 2) my almost 20 years old Ultra-Durable Gigabyte motherboard
> 3) the Linux system itself.