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Reference Manual: Commands |
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| Chapter 1 Commands |
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| disk reinit |
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| Usage |
disk reinit ensures that master..sysdevices is correct if the master database has been damaged or if devices have been added since the last dump of master.
disk reinit is similar to disk init, but does not initialize the database device.
You can specify the size as a float, but the size is rounded down to the nearest multiple of 2K.
If you do not use a unit specifier for size, disk reinit uses the virtual page size of 2K.
For complete information on restoring the master database, see the System Administration Guide.
Do not set dsync to false for any device that stores critical data. The only exception is tempdb, which can safely be stored on devices for which dsync is set to false.
When dsync is on, writes to the database device are guaranteed to take place on the physical storage media, and Adaptive Server can recover data on the device in the event of a system failure.
When dsync is off, writes to the database device may be buffered by the UNIX file system. The UNIX file system may mark an update as being completed, even though the physical media has not yet been modified. In the event of a system failure, there is no guarantee that data updates have ever taken place on the physical media, and Adaptive Server may be unable to recover the database.
dsync is always on for the master device file.
The dsync value should be turned off only when databases on the device need not be recovered after a system failure. For example, you may consider turning dsync off for a device that stores only the tempdb database.
Adaptive Server ignores the dsync setting for devices stored on raw partitions--writes to those device are guaranteed to take place on the physical storage media, regardless of the dsync setting.
The dsync setting is not used on the Windows NT platform.
disk reinit ensures that master..sysdevices is correct if the master database has been damaged or if devices have been added since the last dump of master.
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