Oracle® Solaris Cluster Concepts Guide

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Updated: July 2014, E39575-01

Cluster File Systems

    Oracle Solaris Cluster software provides a cluster file system based on the Oracle Solaris Cluster Proxy File System (PxFS). The cluster file system has the following features:

  • File access locations are transparent. A process can open a file that is located anywhere in the system. Processes on all cluster nodes can use the same path name to locate a file.

    Note - When the cluster file system reads files, it does not update the access time on those files.
  • Coherency protocols are used to preserve the UNIX file access semantics even if the file is accessed concurrently from multiple nodes.

  • Extensive caching is used along with zero-copy bulk I/O movement to move file data efficiently.

  • The cluster file system provides highly available, advisory file-locking functionality by using the fcntl command interfaces. Applications that run on multiple cluster nodes can synchronize access to data by using advisory file locking on a cluster file system. File locks are recovered immediately from nodes that leave the cluster, and from applications that fail while holding locks.

  • Continuous access to data is ensured, even when failures occur. Applications are not affected by failures if a path to disks is still operational. This guarantee is maintained for raw disk access and all file system operations.

  • Cluster file systems are independent from the underlying file system and volume management software.

You can mount a file system on a global device globally with mount –g or locally with mount.

Programs can access a file in a cluster file system from any node in the cluster through the same file name (for example, /global/foo).

A cluster file system is mounted on all cluster members. You cannot mount a cluster file system on a subset of cluster members.

A cluster file system is not a distinct file system type. Clients verify the underlying file system (for example, UFS).