HP StorageWorks XP Provisioning Manager User Guide (December 2005)

Working With OS-Based Constraints 71
Initial setting: Not specified (does not check file systems during system startup)
Other than the above setting, Provisioning Manager uses the default performance-related settings in Linux. To
improve performance, adjust the settings manually.
4-5-5-2 Notes on Managing Volumes in Small Units
For Provisioning Manager, LUs or volume groupsare management units. If smaller units are necessary, such
as for specifying volumes and physical partitions and setting a usage order, then you must manually create,
expand, or delete applicable file systems and device files by using such methods as OS and volume manager
commands.
4-5-5-3 Notes on Using the RAID Functions
If you want to use the You cannot configure RAID by using Provisioning Manager. Use either of the following
methods to configure RAID:
• Configure RAID by using the functionality of the storage subsystem.
• Configure such RAID software as stripe volume and mirror volume software by manually executing
commands such as the ones for the volume manager.
4-5-5-4 Notes on Creating Many Small Files
When creating many small files with sizes of only a few tens of kilobytes each, you can save disk space by
setting a small value for the file system fragment size. However, the time required to manipulate the file system
will increase.
The following initial values have been set for the file system fragment size:
• ext2: 4,096 bytes
• ext3: 4,096 bytes
To create a file system with a different fragment size, manually change the setting for the fragment size and
then create the file system.
4-5-5-5 Notes on Creating a Journal Log Area for ext3 File Systems
A journal log for an ext3 file system is created with the initial settings in the root directory of the file system by
the file system creation command. If you want to create a journal log on an external device so that it can be
shared, you must set the journal log manually. You can specify the log size as a command option.
4-5-5-6 Notes on Creating and Expanding File Systems in Partitions
Provisioning Manager uses the entire disk to create and expand file systems. If you specify a disk that already
has partitions, Provisioning Manager creates a new label. If you want to create or expand a file system in
partitions, you must specify the settings manually.
4-5-5-7 Notes on the Procedure for Recognizing the Device After Deleting an LU
For a host running on Linux, if an LU is deleted, the OS-managed device name might be changed. If you have
deleted an LU, make sure that you perform the following actions:
1. If the device name is directly specified in /etc/fstab, change it to the new device name.
2. Update the host information.
4-5-5-8 Reason for Unmatched Volume and LU Sizes
In Linux, when an ext2 or ext3 file system is created, the size of the file system is smaller than that of the
volume (LU).
In an ext2 or ext3 file system, 5 percent of the whole area is reserved for use of the superuser only. Therefore,
the created file system is smaller than the volume (LU).
4-6 Restrictions When the Host OS is HP-UX
The following sections describe restrictions and notes when the host OS is HP-UX.
For details about the maximum setting values for manual configuration, see
Table 4-1. in 4-7 .
4-6-1 Prerequisites for the Host
• The Device Manager agent