Correct Use of Raw Partitions

If you choose to use raw partitions, examine your operating system's use of partitions carefully. Otherwise, you may overwrite valuable data. In particular, avoid the following situations:

The following sections describe these situations in detail.


Partition Is Already In Use

Ask your UNIX system administrator what the partition was originally configured for and make sure that it was not designated to serve for any other purpose except for the use of your Adaptive Server. If your partition is used for any other purpose, most of the information it stores might be corrupted or destroyed.


Partition Overlaps with Another Partition

Verify that the partition you intend to use does not share cylinders with another partition. In particular, watch for the following scenarios:


Operating System Is Using Partition for Swap Space

Refer to your operating system administration guide for steps to determine whether a partition is being used for swap space.

For example, on AT&T SVR4 and HP, determine whether your partition is included in the output that is generated, using the following commands:

On AT&T SVR4:

% /etc/swap -l 

On HP-UX:

% /etc/swapinfo
 or 
% /usr/sam/bin/swapinfo

These commands report information on swap partitions only if the entries are found in the file system table.

If the output of these commands includes the device name associated with your database partition, then the device is being used for swap space. Ask your operating system administrator which partition you may use for your database. For more information on how to choose raw partitions, refer to your Adaptive Server installation and configuration guides.


A File System Is Mounted on the Partition

Determine whether your partition is included in the output generated by the following command(s):

% df 

% /etc/mount 

If the output from these commands includes the device name associated with your database partition, ask your operating system administrator to unmount the file system from the partition or to help you choose another disk partition. Note that using the partition as a raw database partition will destroy all file system information that was there.