From owner-freebsd-stable@FreeBSD.ORG Fri Sep 12 05:18:09 2014 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 348F87D6 for ; Fri, 12 Sep 2014 05:18:09 +0000 (UTC) Received: from ipmail05.adl6.internode.on.net (ipmail05.adl6.internode.on.net [150.101.137.143]) by mx1.freebsd.org (Postfix) with ESMTP id B029591A for ; Fri, 12 Sep 2014 05:18:08 +0000 (UTC) Received: from ppp118-210-249-247.lns20.adl6.internode.on.net (HELO leader.local) ([118.210.249.247]) by ipmail05.adl6.internode.on.net with ESMTP; 12 Sep 2014 14:42:57 +0930 Message-ID: <541280D8.9090500@ShaneWare.Biz> Date: Fri, 12 Sep 2014 14:42:56 +0930 From: Shane Ambler User-Agent: Mozilla/5.0 (X11; FreeBSD amd64; rv:24.0) Gecko/20100101 Thunderbird/24.6.0 MIME-Version: 1.0 To: freebsd-stable@freebsd.org Subject: Re: Snapshots that won't delete [was: Re: ZFS on root booting...] References: <7F008C560B48412AB66A1EBD9382DDAE@multiplay.co.uk> <9315C209-701A-49EF-85D3-ACCCD1513EC3@icloud.com> <959C54D2C8EB4AC8983DC1DA3CE042E3@multiplay.co.uk> <9F24DD48FBEA46C39F98DF600D46DA1A@multiplay.co.uk> <4450778127F4407EB6566A0FE11CD651@multiplay.co.uk> <090135D4-8B1F-42B4-82FC-6FD2F1DBDDA8@icloud.com> <20140911071233.GA50585@anubis.morrow.me.uk> In-Reply-To: <20140911071233.GA50585@anubis.morrow.me.uk> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 12 Sep 2014 05:18:09 -0000 On 11/09/2014 16:42, Ben Morrow wrote: > Quoth Adam McDougall : >> >> Were you running a newer kernel with an older format zpool? I heard >> ixsystems had customers doing that and ran into corruption when they >> tried to modify the zpool in some way (expand? I don't remember). >> http://www.bsdnow.tv/episodes/2014_07_09-zfs_war_stories > > Oh! Might this be what's causing a problem I've been meaning to ask > about? > > My desktop at home is running (a patched, but not anywhere to do with > ZFS) 10-STABLE from a while ago, with a zpool that was created under > 8.2-R and is still at version 15. I have been deliberately not upgrading > it, because I saw no reason to and it seemed safer to leave things as > they were. > > Recently, though, my dump script has started having occasional problems > with snapshots that won't delete. Pending further investigation I have > been renaming them to allow the recursive delete to succeed, and (so > far) rebooting has always made it possible to get rid of them. I have seen that issue with 9.2 and at least one other person mentioned it as well. I currently have a snapshot that I accessed at least 3 weeks ago and renamed to keep rotations working and have not accessed since, it still won't delete as it is busy. I can only delete these snapshots after a reboot. The only cause I know is accessing the snapshot. I can simply ls .zfs/snapshot/daily.01/somefolder to prevent it being deleted. With a manual zfs destroy I get "dataset is busy" and have not found a way to find any process that has hold of it. It seems that some aging of the snapshot needs to happen. Testing a rotate, access, rotate keeps working ok, but access last nights snapshot and then rotate and it blocks. I'm fairly sure that I was running 9.1 when I created this zpool and then later upgraded to 9.2. zpool upgrade says "This system supports ZFS pool feature flags" and "Pool 'zrpleader' already has all supported features enabled". -- FreeBSD - the place to B...Serving Data Shane Ambler