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Similar Monitored External Domain=false; Custom External Domain=false; Mimecast External Domain=false; Newly Observed Domain=false; Internal User Name=false; Custom Display Name List=false; Reply-to Address Mismatch=false; Targeted Threat Dictionary=false; Mimecast Threat Dictionary=false; Custom Threat Dictionary=false X-Scanned-By: MIMEDefang 2.79 on 10.11.54.5 X-loop: linux-lvm@redhat.com Subject: [linux-lvm] logical volume usage type code, equivalent to GPT partition type GUID X-BeenThere: linux-lvm@redhat.com X-Mailman-Version: 2.1.12 Precedence: junk Reply-To: LVM general discussion and development List-Id: LVM general discussion and development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linux-lvm-bounces@redhat.com Errors-To: linux-lvm-bounces@redhat.com X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=linux-lvm-bounces@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Hi, I'm wondering to what degree the current LVM metadata format(s) can support additional or even arbitrary metadata. The UEFI spec defines the GPT, and GPT defines a "partition type GUID" for each partition to define it's usage/purpose, in rather open ended fashion. I'm wondering about an equivalent for this with LVM, whether it's useful and how difficult it would be to implement. This is all very hypothetical right now, so a high level discussion is preferred. The starting point is the Discoverable Partitions Spec: http://systemd.io/DISCOVERABLE_PARTITIONS/ Where GPT partition type codes are used to discover file systems, and their intended use without having to explicitly place them into /etc/fstab for startup time discovery and mounting. But LVM doesn't have an equivalent for exposing such a capability, because it implies many volumes within the larger pool and also the pool might comprise many devices. The same problem exists for Btrfs subvolumes, and ZFS datasets. What might be possible and what is definitely not possible, is what I'm interested in understanding for now. Thanks, -- Chris Murphy _______________________________________________ linux-lvm mailing list linux-lvm@redhat.com https://listman.redhat.com/mailman/listinfo/linux-lvm read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/