From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Teigland Date: Tue, 31 Jan 2023 09:55:29 -0600 Subject: Need assistance In-Reply-To: References: Message-ID: <20230131155529.GA16839@redhat.com> List-Id: To: lvm-devel@redhat.com MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit On Mon, Jan 30, 2023 at 06:07:03PM +0530, Gk Gk wrote: > Hi All, > > > I have two nvme disks with different sector sizes of 512 and 4096 > respectively. When I try > to use them in creating a volume group, it is complaining to set the > 'allow_mixed_block_sizes' option in lvm.conf file. But I read elsewhere > that doing this would corrupt data. > > Can anyone explain to me under what specific case/cases will I loose data > if I allow mixed blocked sizes ? If an LV is using one disk, then there is clearly no problem. If an LV is using both disks, then we don't know all the issues that might appear -- linear/striped will be fine, but we've seen problems with cache, writecache, snapshot. Avoid pvmove or something where the disk under a logical block might change.