I think having a native cephfs driver without nfs in the cloud is a very compelling feature. nfs is nearly impossible to make both HA and Scalable without adding really expensive dedicated hardware. Ceph on the other hand scales very nicely and its very fault tollerent out of the box.
Thanks, Kevin ________________________________________ From: Shinobu Kinjo [ski...@redhat.com] Sent: Friday, September 25, 2015 12:04 AM To: OpenStack Development Mailing List (not for usage questions); John Spray Cc: Ceph Development; openstack-dev@lists.openstack.org Subject: Re: [openstack-dev] [Manila] CephFS native driver So here are questions from my side. Just question. 1.What is the biggest advantage comparing others such as RDB? We should be able to implement what you are going to do in existing module, shouldn't we? 2.What are you going to focus on with a new implementation? It seems to be to use NFS in front of that implementation with more transparently. 3.What are you thinking of integration with OpenStack using a new implementation? Since it's going to be new kind of, there should be differ- ent architecture. 4.Is this implementation intended for OneStack integration mainly? Since velocity of OpenStack feature expansion is much more than it used to be, it's much more important to think of performance. Is a new implementation also going to improve Ceph integration with OpenStack system? Thank you so much for your explanation in advance. Shinobu ----- Original Message ----- From: "John Spray" <jsp...@redhat.com> To: openstack-dev@lists.openstack.org, "Ceph Development" <ceph-de...@vger.kernel.org> Sent: Thursday, September 24, 2015 10:49:17 PM Subject: [openstack-dev] [Manila] CephFS native driver Hi all, I've recently started work on a CephFS driver for Manila. The (early) code is here: https://github.com/openstack/manila/compare/master...jcsp:ceph It requires a special branch of ceph which is here: https://github.com/ceph/ceph/compare/master...jcsp:wip-manila This isn't done yet (hence this email rather than a gerrit review), but I wanted to give everyone a heads up that this work is going on, and a brief status update. This is the 'native' driver in the sense that clients use the CephFS client to access the share, rather than re-exporting it over NFS. The idea is that this driver will be useful for anyone who has such clients, as well as acting as the basis for a later NFS-enabled driver. The export location returned by the driver gives the client the Ceph mon IP addresses, the share path, and an authentication token. This authentication token is what permits the clients access (Ceph does not do access control based on IP addresses). It's just capable of the minimal functionality of creating and deleting shares so far, but I will shortly be looking into hooking up snapshots/consistency groups, albeit for read-only snapshots only (cephfs does not have writeable shapshots). Currently deletion is just a move into a 'trash' directory, the idea is to add something later that cleans this up in the background: the downside to the "shares are just directories" approach is that clearing them up has a "rm -rf" cost! A note on the implementation: cephfs recently got the ability (not yet in master) to restrict client metadata access based on path, so this driver is simply creating shares by creating directories within a cluster-wide filesystem, and issuing credentials to clients that restrict them to their own directory. They then mount that subpath, so that from the client's point of view it's like having their own filesystem. We also have a quota mechanism that I'll hook in later to enforce the share size. Currently the security here requires clients (i.e. the ceph-fuse code on client hosts, not the userspace applications) to be trusted, as quotas are enforced on the client side. The OSD access control operates on a per-pool basis, and creating a separate pool for each share is inefficient. In the future it is expected that CephFS will be extended to support file layouts that use RADOS namespaces, which are cheap, such that we can issue a new namespace to each share and enforce the separation between shares on the OSD side. However, for many people the ultimate access control solution will be to use a NFS gateway in front of their CephFS filesystem: it is expected that an NFS-enabled cephfs driver will follow this native driver in the not-too-distant future. This will be my first openstack contribution, so please bear with me while I come up to speed with the submission process. I'll also be in Tokyo for the summit next month, so I hope to meet other interested parties there. All the best, John __________________________________________________________________________ OpenStack Development Mailing List (not for usage questions) Unsubscribe: openstack-dev-requ...@lists.openstack.org?subject:unsubscribe http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev __________________________________________________________________________ OpenStack Development Mailing List (not for usage questions) Unsubscribe: openstack-dev-requ...@lists.openstack.org?subject:unsubscribe http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev __________________________________________________________________________ OpenStack Development Mailing List (not for usage questions) Unsubscribe: openstack-dev-requ...@lists.openstack.org?subject:unsubscribe http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev
