From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mx1.redhat.com (ext-mx05.extmail.prod.ext.phx2.redhat.com [10.5.110.29]) by int-mx14.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id u5C0b5sZ021245 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO) for ; Sat, 11 Jun 2016 20:37:05 -0400 Received: from mail-pf0-f173.google.com (mail-pf0-f173.google.com [209.85.192.173]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id BA7033BF557 for ; Sun, 12 Jun 2016 00:37:04 +0000 (UTC) Received: by mail-pf0-f173.google.com with SMTP id c2so34428446pfa.2 for ; Sat, 11 Jun 2016 17:37:04 -0700 (PDT) Received: from [192.168.1.2] ([121.99.178.58]) by smtp.googlemail.com with ESMTPSA id p1sm27134991pfb.73.2016.06.11.17.37.02 for (version=TLSv1/SSLv3 cipher=OTHER); Sat, 11 Jun 2016 17:37:03 -0700 (PDT) From: sergei Message-ID: <575CAE9A.1060001@gmail.com> Date: Sun, 12 Jun 2016 12:36:42 +1200 MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: [linux-lvm] LVM cache/dm-cache questions. Reply-To: LVM general discussion and development List-Id: LVM general discussion and development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , List-Id: Content-Type: text/plain; charset="us-ascii"; format="flowed" To: linux-lvm@redhat.com Hi, I have a few simple questions regarding relatively new feature LVM cache/dm-cache. From second hand information on internet, it appears that you cannot resize cached volume. Please correct me if I am wrong: to resize a cached volume, one needs to lvremove the cache, resize and recreate the cache? In scenario where cache device fails, how safe is the data on the cached LVM? Is it possible to make snapshots of the cached device? Before I test these things I will need to upgrade distribution (as the release I am on does not have the LVM cache), which means switching to systemd (I would rather avoid, if LVM cache does not fail gracefully). Thank you very much! Sergei.