The distributed NFS solution

Network latency and remote connectivity

Network attached storage (NAS) appliances are used to consolidate data and provide shared access to files over wide area networks (WANs). Large, geographically distributed organizations have high-speed local area networks (LANs) where data for each site is consolidated and administered from a central data repository.

Although data management at a central location is efficient, low bandwidth and high latency complicate long-distance connectivity for remote or branch offices. For example, remote offices experience delays in transferring large files for certain applications, and the WAN must be shared for all remote-office needs.

Maintaining network performance and connectivity to support distributed file systems is a fundamental challenge that administrators face every day. For example, remote offices often have no resident IT staff, and backup of remote office storage can be problematic.

What is a distributed NFS appliance?

A distributed NFS appliance is a device that supports remote data distribution within NFS client and NFS server configurations.

The appliance is an NFS proxy file server that

Can interface with applications as if the applications were in direct communication with an NFS source filer
Provides cached access to data originating from file servers in geographically distributed locations

Supported origin servers

A distributed NFS appliance supports the following NFS server operating systems:

NetApp Filers
Solaris 5.7/5.8 TCP/UDP V2/V3
Red Hat Linux 7.1/7.2 UDP V2/V3. TCP is not supported when using Linux file servers. The reason is that these Linux versions do not have TCP server functionality built in.

Protocols and NFS versions supported

Currently, the distributed NFS appliance offers support for certain protocols and NFS versions. Specifically, the appliance

Supports NFS in TCP and UDP mode
Supports both NFS version 2 and NFS version 3
Supports NLM
Supports NIS
Does not support HTTP, streaming, NNTP, or FTP
Does not support the Solaris nfs_acl protocol

File sharing solutions

The appliance offers the following solutions for issues inherent to file sharing:

Increases performance
The appliance consolidates data closer to the end user where cached access improves response time for users in remote locations.
Reduces load on network infrastructure
The appliance assists NFS file servers by acting as a proxy to maintain and serve data.
Reduces bandwidth consumption
The appliance eliminates the requirement to maintain and administer full dataset replication to service remote locations.
Simplifies remote administration
Administrative functions for the appliance are performed from the central data location.
Ensures data consistency
The appliance verifies object maturity at periodic intervals (set by an administrator) to ensure that data is consistent with the source storage device at the data center.