From owner-freebsd-fs@FreeBSD.ORG Fri Oct 30 22:00:21 2009 Return-Path: Delivered-To: freebsd-fs@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 60460106566B for ; Fri, 30 Oct 2009 22:00:21 +0000 (UTC) (envelope-from zbeeble@gmail.com) Received: from mail-ew0-f209.google.com (mail-ew0-f209.google.com [209.85.219.209]) by mx1.freebsd.org (Postfix) with ESMTP id EEE1F8FC14 for ; Fri, 30 Oct 2009 22:00:20 +0000 (UTC) Received: by ewy5 with SMTP id 5so63665ewy.36 for ; Fri, 30 Oct 2009 15:00:20 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:received:date:message-id:subject :from:to:content-type; bh=PLcfqdR4EM0JNdGz74+c/D9OkY3kNsW2Mb2vRJOL19k=; b=BTf6pVqNGkudwc9TxP3SQR9BC2cU/UD7CdaASzRFys+GRshKJ4/heI48hMorJoRoiU GdnlQ7vhZnzz1yO4DLsi/e+lipr3WtbOW7DXLX6SmVi2HKtwkcUzUFeKUS4LkRfCjwR8 OvcN7xcEJP0dWPmyv4dzDDZR+TKhGs39EzCIs= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:date:message-id:subject:from:to:content-type; b=gnpbSjPT3kR35QQHFB3RTybStyJlNcY+ETMDRQhHatwClMZD3+bcNVjni7v4A5tbHb 5SYn7PjkqdlfPkq2TZg/TMoH3q7nWAHuvk3tvFawI10fiLkXYJLwGzreGVbFFjMxPF+S +6BJm1d/wOvBV3CvS+kvlW9L3kfHOdoy00RKI= MIME-Version: 1.0 Received: by 10.216.85.137 with SMTP id u9mr783568wee.214.1256940019894; Fri, 30 Oct 2009 15:00:19 -0700 (PDT) Date: Fri, 30 Oct 2009 18:00:19 -0400 Message-ID: <5f67a8c40910301500t4b3d3434ha70cc32b66842795@mail.gmail.com> From: Zaphod Beeblebrox To: freebsd-fs@freebsd.org Content-Type: text/plain; charset=ISO-8859-1 X-Content-Filtered-By: Mailman/MimeDel 2.1.5 Subject: Reading allegedly bad ZFS blocks X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 30 Oct 2009 22:00:21 -0000 I have a system I suspect of not being entirely sane. It has accused some files in my ZFS RAIDZ1 array of being corrupt --- ie: not enough information to recover them. However, I suspect strongly that the data may be OK and simply the system itself (reading those blocks) was bad. Now... I attach the ZFS array to a new system ... and the new system refuses to check those files again --- they are "known" bad when I first import the filesystem. I would like the ability to read the underlying data again --- possibly re-check the checksum ... or just get the whole file. Current ZFS behaviour is to return EIO for any of the blocks it doesn't wish to read. Someone in the archives mentioned patching ZFS to ignore it's checksums. Strikes me this should be sysctl. Could someone post that patch?