Administrator's Guide

Technical Overview

VxFS Functionality on Cluster File Systems

Chapter 1

VxFS Functionality on Cluster File Systems

The HP Serviceguard Storage Management Suite uses the Veritas File System (VxFS).

Most of the major features of VxFS local file systems are available on cluster file

systems, including:

• Extent-based space management that maps files up to 1 terabyte in size

• Fast recovery from system crashes using the intent log to track recent file system

metadata updates

• Online administration that allows file systems to be extended and defragmented

while they are in use

Supported Features

The following table lists the features and commands that are available and supported

with CFS. Every VxFS online manual page has a Cluster File System Issues section that

informs you if the command functions on cluster-mounted file systems, and indicates any

difference in behavior from how the command functions on local mounted file systems.

Table 1-1 CFS Supported Features

Features and Commands Supported on CFS

Quick I/O The clusterized Oracle Disk Manager (ODM) is supported with CFS

using the Quick I/O for Databases feature in the following HP

Serviceguard Storage Management Suite CFS bundles for Oracle:

For HP-UX 11i v2 - T2776CA, T2777CA, T2796CA, and T2797CA

For HP-UX 11i v3 - T2776CB, T2777CB, T8686CB, T8687CB,

T8696CB, and T8697CB

Storage

Checkpoints

Storage Checkpoints are supported with CFS.

Freeze and

Thaw

Synchronizing operations, which require freezing and thawing file

systems, are done on a cluster-wide basis.

Snapshots Snapshots are supported with CFS.

Quotas Quotas are supported with CFS.

NFS Mounts You can mount cluster file systems to NFS.

Memory

Mapping

Shared memory mapping established by the map() function is

supported on CFS. See the mmap(2) manual page.

Concurrent

I/O

This feature extends current support for concurrent I/O to cluster file

systems. Semantics for concurrent read/write access on a file in a

cluster file system matches those for a local mount.

Delaylog The -o delaylog mount option is supported with cluster mounts.

This is the default state for CFS.