From owner-freebsd-virtualization@freebsd.org Wed Aug 26 21:25:54 2015 Return-Path: Delivered-To: freebsd-virtualization@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id B3F149C2B2D for ; Wed, 26 Aug 2015 21:25:54 +0000 (UTC) (envelope-from vivek@khera.org) Received: from mail-wi0-x229.google.com (mail-wi0-x229.google.com [IPv6:2a00:1450:400c:c05::229]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4C7AB1451 for ; Wed, 26 Aug 2015 21:25:54 +0000 (UTC) (envelope-from vivek@khera.org) Received: by wicja10 with SMTP id ja10so56458186wic.1 for ; Wed, 26 Aug 2015 14:25:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=khera.org; s=google11; h=mime-version:date:message-id:subject:from:to:content-type; bh=QJQkTJVCRj18givgZtOqSU+0qxLHTOmqUJ+ti6mjnUQ=; b=OD1r8Iy0Zan0ChwNxMlZ1qj2/fRDqiRGg6W+7Tgm2SaIHP72B6MrmkEeisjsY1Jkm/ f9P+6kfzuY6T0SskKAmVURwMUgk7JuZpAXTqlkjCQ8Ji/3cpJPR0JvtAjVqkhQMUfvo+ 0UJor6q1SZ8O9maN8xtJUhd1itusRjWDEtMjc= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:date:message-id:subject:from:to :content-type; bh=QJQkTJVCRj18givgZtOqSU+0qxLHTOmqUJ+ti6mjnUQ=; b=Kmbom/G5Pg8Mq157XnuFX8E3qHN4u//kzW+Lg0cc39EGCNcv2a4JaROdd/FY+g7WIZ sQ/c3k6CaNc+xj7sG49hxY6epbqhbINPGP3HFt7HS1XwBfKGR4EaAuYOHGCgFSfIChFi PsdMiO3eF5DcgXPpjCEDCCiXtgqARpP6z5tiHL34xBfdI1RULe3MFy0LNUaUSEILcpeS STQxPXxI/5EODYs4r8D4TiZ0ztT4YRhKFydOEmgL0PVpxqqs768vC58Hiw2xD3gIrSeG NknskL4hLHLpKAT9YvFmW5lPkYwMcjg/hbPkypa5m5nfImsHqi2SSgBH1hYAIh1y1Pck QshQ== X-Gm-Message-State: ALoCoQl7u8B64Eb61hL8WjnfuBmCeB0RGRSBIVoEI5rgyKX9ddrbVBprI4Ld3OtQagji9wugXTRp MIME-Version: 1.0 X-Received: by 10.180.187.137 with SMTP id fs9mr15662728wic.10.1440624352805; Wed, 26 Aug 2015 14:25:52 -0700 (PDT) Received: by 10.28.188.132 with HTTP; Wed, 26 Aug 2015 14:25:52 -0700 (PDT) Date: Wed, 26 Aug 2015 17:25:52 -0400 Message-ID: Subject: Options for zfs inside a VM backed by zfs on the host From: Vick Khera To: freebsd-virtualization@freebsd.org Content-Type: text/plain; charset=UTF-8 X-Content-Filtered-By: Mailman/MimeDel 2.1.20 X-BeenThere: freebsd-virtualization@freebsd.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: "Discussion of various virtualization techniques FreeBSD supports." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 26 Aug 2015 21:25:54 -0000 I'm running FreeBSD inside a VM that is providing the virtual disks backed by several ZFS zvols on the host. I want to run ZFS on the VM itself too for simplified management and backup purposes. The question I have is on the VM guest, do I really need to run a raid-z or mirror or can I just use a single virtual disk (or even a stripe)? Given that the underlying storage for the virtual disk is a zvol on a raid-z there should not really be too much worry for data corruption, I would think. It would be equivalent to using a hardware raid for each component of my zfs pool. Opinions? Preferably well-reasoned ones. :)