Re: [current-users] Re: Best practice for setting up disks for ZFS on NetBSD

[HIROSE yuuji <yuuji-netbsd%es.gentei.org@localhost>]

>> On Thu, 03 Dec 2020 18:19:05 +1100
>> mjch%mjch.net@localhost ("Malcolm Herbert") said:
> 
> As far as I understand it, ZFS vdevs have their own ID, so they can be laid out correctly no matter the OS device each are discovered on ... wouldn't that make a raidframe wrapper redundant?  it would also mean the zpool vdevs couldn't be used on other systems that understand ZFS because they're unlikely to understand raidframe ...

My knowledge about ZFS is the same.
I never care about device numbers for zpool disks on FreeBSD.

But I found that NetBSD-9.1 STABLE(23 Oct) couldn't find zpool after
reconnecting external SSD as sd1, which was connected as sd0.
In that case, "zpool import" never find last zpool elements anymore.

I tried:
# sed 's,dev/sd0,dev/sd1,g' zpool.cache > zpool.cache2
# zpool import -c zpool.cache2 -a
These operation were needed every time when sdX number moved.

I've not tested on newer kernel.
Recent kernel detect pool IDs smoothly??

Anyway I needed to get the host stable state at that time,
I constructed redundant raidframe and found working fine for me.

This should be a dirty workaround for a short term...

--yuuji

> 
> Regards,
> Malcolm
> 
> On Thu, 3 Dec 2020, at 12:00, HIROSE yuuji wrote:
> > >> On Thu, 3 Dec 2020 00:30:17 +0000
> > >> abs%absd.org@localhost (David Brownlee) said:
> > > 
> > > What would be the best practice for setting up disks to use under ZFS
> > > on NetBSD, with particular reference to handling renumbered devices?
> > > 
> > > The two obvious options seem to be:
> > > 
> > > - Wedges, setup as a single large gpt partition of type zfs (eg /dev/dk7)
> > > - Entire disk (eg: /dev/wd0 or /dev/sd4)
> > > 
> > 
> > Creating raidframe for thoset wedges or disks and "raidframe -A yes"
> > would be helpful to create stable device-name for zpool.
> > 
> > I prefer to use dummy raidframe even if the host has only single device
> > to make HDD/SSDs bootable when they attached to USB-SATA adapters.
> > 
> > --yuuji
> >
> 
> -- 
> Malcolm Herbert
> mjch%mjch.net@localhost