VERITAS Storage Foundation 4.1 Oracle Administrator's Guide

Using VERITAS NetBackup to Backup and Restore Quick I/O Files Prerelease 8 September 2005, 8:55am
262 VERITAS Storage Foundation for Oracle Administrator’s Guide
Using VERITAS NetBackup to Backup and Restore Quick I/O
Files
The information in this section assumes that you are not using NetBackup for Oracle to back up
and restore Quick I/O files. If you are using NetBackup for Oracle, instead refer to “Using Oracle
RMAN to Back Up and Restore Quick I/O Files” on page 497.
VERITAS NetBackup does not follow symbolic links when backing up files. Typical backup
management applications are designed this way to avoid backing up the same data twice. This
would happen if both the link and the file it points to were included in the list of files to be backed
up.
A Quick I/O file consists of two components: a hidden file with the space allocated for it, and a link
that points to the Quick I/O interface of the hidden file. Because NetBackup does not follow
symbolic links, you must specify both the Quick I/O link and its hidden file in the list of files to be
backed up.
Example
To view all files and their attributes in the db01 directory:
$ ls -la /db01
total 2192
drwxr-xr-x 2 root root 96 Oct 20 17:39 .
drwxr-xr-x 9 root root 8192 Oct 20 17:39 ..
-rw-r--r-- 1 oracle dba 1048576 Oct 20 17:39 .dbfile
lrwxrwxrwx 1 oracle dba 22 Oct 20 17:39 dbfile ->\
.dbfile::cdev:vxfs:
In the example above, you must include both the symbolic link dbfile and the hidden file
.dbfile in the file list of the backup class.
If you want to back up all Quick I/O files in a directory, you can simplify the process by just
specifying the directory to be backed up. In this case, both components of each Quick I/O file will
be properly backed up. In general, you should specify directories to be backed up unless you only
want to back up some, but not all files, in those directories.
Because VERITAS NetBackup is integrated with VERITAS Storage Foundation for Oracle,
VERITAS NetBackup backs up extent attributes of a Quick I/O file and restores them accordingly.
Quick I/O files can then be backed up and restored as regular files using VERITAS NetBackup,
while preserving the Quick I/O file’s extent reservation. Without this feature, restoring the file
could cause the loss of contiguous reservation, which can degrade performance.
When restoring a Quick I/O file, if both the symbolic link and the hidden file already exist,
VERITAS NetBackup will restore both components from the backup image. If either one or both of
the two components are missing, VERITAS NetBackup creates or overwrites as needed.