Accessing regular VxFS files as Quick I/O files
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Accessing regular VxFS files as Quick I/O files

You can access regular VxFS files as Quick I/O files using the ::cdev:vxfs: name extension.

While symbolic links are recommended because they provide easy file system management and location transparency of database files, the drawback of using symbolic links is that you must manage two sets of files (for instance, during database backup and restore).

Usage notes

  • If possible, use relative path names instead of absolute path names when creating symbolic links to access regular files as Quick I/O files. Using relative path names prevents copies of the symbolic link from referring to the original file when the directory is copied. This is important if you are backing up or moving database files with a command that preserves the symbolic link.

    However, some applications require absolute path names. If a file is then relocated to another directory, you must change the symbolic link to use the new absolute path. Alternatively, you can put all the symbolic links in a directory separate from the data directories. For example, you can create a directory named /database and put all the symbolic links there, with the symbolic links pointing to absolute path names.

To access an existing regular file as a Quick I/O file on a VxFS file system

  1. Access the VxFS file system mount point containing the regular files:
    $ cd /mount_point
  2. Create the symbolic link:
    $ mv filename .filename
$ ln -s .filename::cdev:vxfs: filename

    This example shows how to access the VxFS file dbfile as a Quick I/O file:

    $ cd /db01
$ mv dbfile .dbfile
$ ln -s .dbfile::cdev:vxfs: dbfile

    This example shows how to confirm the symbolic link was created:

    $ ls -lo .dbfile dbfile

    For DB2:

    -rw-r--r--	 1 db2inst1	104890368	Oct 2 13:42	 .dbfile
    lrwxrwxrwx		1 db2inst1		  19		   Oct 2 13:42		 dbfile -> 	
.dbfile::vxcdev:vxfs:

    For Sybase:

    $ ls -lo .dbfile dbfile
    -rw-r--r--	 1 sybase		104890368		Oct 2 13:42		.dbfile
    lrwxrwxrwx		1 sybase						19		   Oct 2 13:42			dbfile -> 	
.dbfile::cdev:vxfs:
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