All disk backups write to the file system; raw disk backup is not supported. All disks on a redundant array of independent devices (RAID) device are treated as a single device.
BACKUP appends a suffix to the archive_device name to assign file names to disk backup files. The suffix consists of "." followed by a number that increases by one for each new file. For example, if you specify /iqback/mondayinc as the archive_device, the backup files are /iqback/mondayinc.1, /iqback/mondayinc.2, and so on. This convention allows you to store as large a backup as you need, while allowing you control over the file size; see the SIZE option for details. To accommodate this convention, your file system must support long file names.
BACKUP does not create missing directories. If you try to start a backup in a directory that does not exist, the backup fails.
Do not use relative path names for disk file locations. BACKUP interprets the path name as relative to the location where the server was started, which you may not be able to identify with certainty when you do a backup. If there is data in other directories along the path, you may not have enough disk space to perform the backup.
BACKUP determines how much disk space is required to back up your database. If there is not enough disk space available, the backup fails before writing any data.
Use the optional SIZE parameter to define backup file sizes. The SIZE value can be less than or greater than the default disk size. Backups that do not include SIZE parameters proceed until the backup is complete (backup is less than disk capacity) or the disk is full.
The SIZE value is expressed kilobytes (KB). SIZE does not limit the number of bytes per device. SIZE limits the file size.
During backup, when the amount of information written to a given file exceeds the default disk size, or reaches the value specified by the SIZE parameter, BACKUP closes the current file and creates another file of the same name, with the next ascending number appended to the file name. For example, bkup1.dat1.1, bkup1.dat1.2, bkup1.dat1.3.
An unattended backup that runs out disk space fails. An attended backup closes all open backup files and prompts you to free up additional disk space (8KB minimum). When the additional space becomes available, the backup resumes with new backup files.
BACKUP overwrites existing disk files of the same name. To retain a previous backup, use different file or path names for the archive devices, or move the old backup to another location.
If you back up to disk, then move the backups to tape, move the backups back to disk with the same file names you used when you created the tape backup. SAP Sybase IQ cannot restore disk backups from the tapes where you moved the tape backups. When you restore from disk, you must specify the same number of archive devices (disk files) for the restore as were used to create the backup.