Date: Tue, 22 Jul 2008 14:44:42 +0200 From: =?utf-8?Q?Dag-Erling_Sm=C3=B8rgrav?= <des@des.no> To: Pawel Jakub Dawidek <pjd@FreeBSD.org> Cc: Peter Jeremy <peterjeremy@optushome.com.au>, Remko Lodder <remko@freebsd.org>, src-committers@freebsd.org, "current@freebsd.org" <current@freebsd.org> Subject: Re: geom_mirror silently upgrading metadata Message-ID: <86fxq2ozph.fsf@ds4.des.no> In-Reply-To: <20080718070624.GC1976@garage.freebsd.pl> (Pawel Jakub Dawidek's message of "Fri\, 18 Jul 2008 09\:06\:24 %2B0200") References: <200807131153.m6DBrDkX067657@repoman.freebsd.org> <487C6A86.20508@FreeBSD.org> <20080715095139.GA62764@server.vk2pj.dyndns.org> <20080718070624.GC1976@garage.freebsd.pl>
next in thread | previous in thread | raw e-mail | index | archive | help
Pawel Jakub Dawidek <pjd@FreeBSD.org> writes: > Just to be clear. I fully agree with you guys. What I could do about > that when I was working on gmirror (starting from the simplest > solution): > > 1. Skip disks which have version lower then what we have in the kernel. > > 2. Upgrade the on-disk metadata automatically. > > 3. Make gmirror kernel module to work with all the previous versions and > add 'gmirror upgrade' command, so one can upgrade on-disk metadata. 4. Allow an older mirror to be accessed r/o by a newer kernel, side- stepping the issue of converting metadata back to the old format. Require an explicit 'gmirror upgrade' to upgrade the metadata and allow r/w access. IIRC, this is what ZFS does. I believe it would be a good compromise between 2 and 3. DES --=20 Dag-Erling Sm=C3=B8rgrav - des@des.no
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?86fxq2ozph.fsf>