Re: ZFS on a shared iSCSI

From: Julien Cigar <julien_at_perdition.city>
Date: Wed, 07 Feb 2024 12:24:29 UTC
On Wed, Feb 07, 2024 at 11:55:54AM +0100, Andrea Brancatelli wrote:
> Hello guys, I'm not 100% this is the correct list to ask this question, if
> not please feel free to point me in the right direction.
> 
> I was wondering what could be the best recipe to have an HA cluster sharing
> an external ZFS storage.
> 
> Let's say I have two servers running a bunch of Jails and, thus, I'd like
> to use ZFS as the underlying storage layer and I have an external (iSCSI)
> storage connected.
> 
> Would it be "easily possible" to have some (2?) iSCSI LUN exposed to both
> servers and then activate the pool on one or the other server?
> 
> The idea would be to reactivate the filesystem from server A on server B if
> the server A fails.
> 
> Would it be "easier" to replicate everything and zfs send datas back and
> forth? Clearly that would mean doubling datas and havin a scheduled replica
> with a possible delay in data replication, so I'd like to avoid this.
> 
> Any thoughts?

I asked something similar a few years ago, the whole thread may be an interesting
read: https://lists.freebsd.org/pipermail/freebsd-fs/2016-June/023456.html

Just to say that I tried a lot of different things, and came up to the
conclusion that for critical production usage all those things are
fragile and with hidden dragons everywhere.

I love FreeBSD (I use it exclusively everywhere, also at work), but
there aren't any supported open-source solution for something like an
"highly available ZFS cluster". On the commercial side there is RSF-1
and beasts like Pure storage ($$$) but ...

I would really like to see CEPH ported to FreeBSD, that would be
extremely useful

Julien

> 
> Thanks a lot.
> 
> -- 
> *Andrea Brancatelli*

-- 
Julien Cigar
Belgian Biodiversity Platform (http://www.biodiversity.be)
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