Open System Services Management and Operations Guide (G06.30+, H06.08+, J06.03+)

3 Understanding the OSS File System
To manage the Open System Services (OSS) environment effectively, you must understand the OSS
file system.
The OSS file system works in the same way as a UNIX file system from the point of view of the
user. Files in the OSS environment are organized in a hierarchical tree structure. For further
information about using the tree structure, see the Open System Services User’s Guide. For
information about the content of the tree structure as released by HP, see the hier(5) reference
page either online or in the Open System Services System Calls Reference Manual.
The OSS file system consists of one or more filesets. Each fileset is a hierarchy of files: a set of
directories, subdirectories, and files themselves.
A fileset can have other filesets mounted on directories in it. In fact, the collection of directories
and files under the root directory is part of one fileset. Every file belongs to a fileset. You control
the operation of filesets as described in “Managing Filesets” (page 140).
Every file has an OSS pathname. The OSS pathname consists of one or more OSS filenames and
helps locate the file within the tree structure.
The following subsections provide a brief overview of the relationships between OSS pathnames
and Guardian filenames and an overview of the tree structure. Later subsections describe how the
OSS name servers maintain and use these relationships for access to the filesets they manage.
OSS Pathnames
An OSS pathname describes a path through the OSS directory tree to a file. The length of OSS
pathnames is limited:
• Each OSS directory name or OSS filename in an OSS pathname can contain up to 248
characters.
• OSS pathnames can contain up to 1024 characters.
An OSS file can have more than one pathname, using either hard or symbolic links:
• An OSS file can have as many as 128 links (128 OSS pathnames can point to the same file).
• As many as 20 symbolic links can be followed when resolving an OSS pathname.
For further information about OSS files and pathnames, see the Open System Services User’s Guide
and to the filename(5) reference page either online or in the Open System Services System
Calls Reference Manual.
OSS pathnames are logical names; they have no connection to storage devices. The relationship
of OSS files to disk volumes is illustrated in Figure 8.
80 Understanding the OSS File System