0 December 2005
"NFSv4 News and Views" with Dr. Peter Honeyman Brief History of NFVv4 -------------------------------------------- v4 adds things naming and security to NFS It tosses the mount protocol in favor of security at a much lower layer. Security -------------------------------------------- RPCSEC_GSS: GSS security flavor for ONC/RPC Mandatory mechanisms: K5, LIPKEY ACLs no mount protocol Locking and delegation -------------------------------------------- Lease-based mandatory byte-range locks CIFS-like "shares" Deny bits on open Delegation, modeled after "op locks", grants control to client Never mandatory to offer or accept Delegation is offered in response to open Makes locks fast, reduces network traffic Callback path Minor version numbers -------------------------------------------- Regular (annual?) extension mechanism NFSv4.1 will have neat stuff in it -- stay tuned Compound RPC -------------------------------------------- IMHO mostly to clean up the protocol spec Tacit GETATTR is now an explicit optimization Possibly other optimizations At mount time On first access NFVv4 features -------------------------------------------- Name space, migration, replication -------------------------------------------- /nfs/citi.umich.edu/user/honey/ Use DNS to find NFS server(s) mount one Extend FS_LOCATIONS to directories Lazy primary server for replication Migration -------------------------------------------- Is a special case of replication ... I guess ... isn't it? Wanted, dead or alive: administrative clue Parallel access -------------------------------------------- Cluster File System -------------------------------------------- Every node is a fully capable client, data server, and metadata server Examples: IBM GPFS, Redhat GFS, Polyserve Matrix Server Parallel file systems -------------------------------------------- Clietns access storage directly Separate metadata server(s) Object Based: Lustre, Panasas ActiveScale Block Baed: EMC High Road, IBM SAN FS NFS and HPC File Systems -------------------------------------------- Single server bottle neck Extra level of indirection pNFS -------------------------------------------- [nice diagrams] RDMA (Remote DMA) -------------------------------------------- Direct I/O -- true zero copy "Chunks direct data transfer between client memory and server buffers ONC/RPC over RDMA New transport type and frame Bindings for NFSv2/v3/v4 GridNFS NFSv4 and the Grid are simultaneously poised for exponential growth in influence. . . . -------------------------------------------- Directory delegation -------------------------------------------- NFVv4 futures --------------------------------------------