From owner-freebsd-stable@FreeBSD.ORG Sun Sep 14 11:40:00 2014 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [8.8.178.115]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id C7FF689F for ; Sun, 14 Sep 2014 11:40:00 +0000 (UTC) Received: from smtp.digiware.nl (unknown [IPv6:2001:4cb8:90:ffff::3]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 5A6C2BF9 for ; Sun, 14 Sep 2014 11:39:59 +0000 (UTC) Received: from rack1.digiware.nl (unknown [127.0.0.1]) by smtp.digiware.nl (Postfix) with ESMTP id E8D4E1534D2; Sun, 14 Sep 2014 13:39:56 +0200 (CEST) X-Virus-Scanned: amavisd-new at digiware.nl Received: from smtp.digiware.nl ([127.0.0.1]) by rack1.digiware.nl (rack1.digiware.nl [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id I3_poFX4nv85; Sun, 14 Sep 2014 13:39:54 +0200 (CEST) Received: from [192.168.10.9] (vaio [192.168.10.9]) (using TLSv1 with cipher ECDHE-RSA-AES128-SHA (128/128 bits)) (No client certificate requested) by smtp.digiware.nl (Postfix) with ESMTPSA id 399001534C4; Sun, 14 Sep 2014 13:39:54 +0200 (CEST) Message-ID: <54157E8A.9060301@digiware.nl> Date: Sun, 14 Sep 2014 13:39:54 +0200 From: Willem Jan Withagen User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:24.0) Gecko/20100101 Thunderbird/24.6.0 MIME-Version: 1.0 To: Steven Hartland , Shane Ambler , 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> <541280D8.9090500@ShaneWare.Biz> In-Reply-To: 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: Sun, 14 Sep 2014 11:40:01 -0000 On 12-9-2014 10:19, Steven Hartland wrote: > Is there a hold on the snapshot? > > ----- Original Message ----- From: "Shane Ambler" > > >> 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". I've had more or less the same happen to me in a backup-with-snapshot script... The solution that worked from me uptill now is: zfs unmount -f For me that is easy to do, since this pool holds a remote backup, and is only written at nighttime. So at other times there is no harm if I unmount.... But if you normally "live" in the pool, that might be somewhat harder. --WjW