Chapter 12: Backing Up and Restoring User Databases

Specifying tape density, block size, and capacity

In most cases, the Backup Server uses a default tape density and block size that are optimal for your operating system; Sybase recommends that you use them.

You can specify a density, block size, and capacity for each dump device. You can also specify the density, blocksize, and capacity options in the with clause for all dump devices. Characteristics that are specified for an individual tape device take precedence over those that you specify using the with clause.

Table 12-8 shows the syntax for specifying the tape density, block size, and capacity.

**Table 12-8: Specifying tape density, block size, and capacity**
	Backing up a database or log	Loading a database or log
	`dump {database \| tran} database_name to [compress::[compression_level::]] stripe_device [at backup_server_name]`	`load {database \| tran} database_name from [compress::]stripe_device [at backup_server_name]`
Characteristics of a single tape device	`[density = density, blocksize = number_bytes, capacity = number_kilobytes,`	`[density = density,`
	`dumpvolume = volume_name, file = file_name] [stripe on [compress::[compression_level::]] stripe_device [at backup_server_name] [density = density, blocksize = number_bytes, capacity = number_kilobytes, dumpvolume = volume_name, file = file_name] ...]`	`dumpvolume = volume_name, file = file_name] [stripe on [compress::]stripe_device [at backup_server_name] [density = density, dumpvolume = volume_name, file = file_name] ...]`
Characteristics of all dump devices	`[with{ density = density, blocksize = number_bytes, capacity = number_kilobytes,`	`[with{ density = density,`
	`dumpvolume = volume_name, file = file_name, [nodismount \| dismount], [nounload \| unload], retaindays = number_days, [noinit \| init], [notify = {client \| operator_console}] standby_access}]`	`dumpvolume = volume_name, file = file_name, [nodismount \| dismount], [nounload \| unload], [notify = {client \| operator_console}]`

The following sections provide greater detail about the density, blocksize, and capacity options.

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