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The New Configuration option enables you to customize the logical drive
configuration to meet the specific needs of your environment. You can configure one or more logical drives with varying RAID levels. You can then add two or more logical drives (unpartitioned) to a logical volume and divide the logical volume into a maximum of 32 partitions.
NOTE: On UNIX systems, if the console locks up during use, you can stop Sun StorEdge Configuration Service by typing ssconsole stop. Then close and reopen the window. The window is displayed again without affecting the agent. Before You Use New Configuration Before you use New Configuration to create a logical drive or a logical volume for the first time, it is useful to familiarize yourself with the information contained in the following steps. Knowing this information ahead of time will ease the process of creating a logical drive or volume.
The optimization mode you select determines the maximum number of disks you can include
in an array and the maximum usable capacity of a logical drive, total array capacity, and stripe size.
Optimization is set in the Cache tab of the Change Controller Parameters window and is set to Sequential by default. For more information on
Sequential I/O and Random I/O, and for steps on how to change the optimization mode, see Changing
Controller Parameters - Cache tab.
If the security of your data is important, leave remaining disks
for standby drives. NOTE: On systems running the Solaris OS,
if the logical drive is going to be larger than 253 Gbyte, see Preparing
for Logical Drives Larger Than 253 Gbyte.
A standby drive is a drive that is marked as a spare to support automatic
data rebuilding after a physical drive associated with a logical drive
fails. For a standby drive to take the place of another drive, it
must be at least equal in size to the failed drive. Also, the failed
drive itself must be from a RAID 1, 3, or 5. A local spare drive is a standby drive assigned to serve one specified
logical drive. When a member drive of this specified logical drive
fails, the local spare drive becomes a member drive and automatically
starts to rebuild. A global spare drive does not only serve one specified logical drive.
When a member drive from any of the logical drives fail, the global
spare drive joins that logical drive and automatically starts to rebuild. Global spares
are used in the order in which they are created.
A partition is a division of the logical drive (or logical
volume). Partitions enable you to create the appearance of having
separate logical drives (or logical volumes) for file management,
multiple users, or other purposes. NOTE: Partitioning can be done during the initial configuration
or after the logical drive has been created. NOTE: Logical drives that have been partitioned cannot be
added to a logical volume.
A smaller logical drive can be created by decreasing this value.
The remainder can be used later by expanding the drive (as explained
in Expanding the Capacity
of a Logical Drive or Logical Volume).
NOTE: The maximum usable capacity for a logical drive is
equal to the smallest physical size disk. For example, if you add
an 18-Gbyte disk and then add a 70-Gbyte disk to be part of the
logical drive, the maximum usable capacity is 18 Gbyte per drive. NOTE: Disk capacity is displayed in powers of 1024. See Device Capacities for specific device capacities.
NOTE: Logical volumes are unsuited to some modern configurations
such as Sun Cluster environments, and do not work in those configurations.
Use logical drives instead. NOTE: Logical drives that have been partitioned cannot be
added to a logical volume.
NOTE: Partitioning can be done during the initial configuration
or after the logical volume has been created.
To Create and Partition a Logical Drive Using New Configuration The following steps provide a working example of creating a new configuration for a new logical drive. Three drives are selected and configured into a RAID 5 logical drive. A small logical drive is then created and partitioned. CAUTION: Back up any existing data to an external device before using the New Configuration command. Sun StorEdge Configuration Service automatically initializes new logical drives defined on the array controller.
Optimization is set in the Cache tab of the Change Controller
Parameters window. For steps on how to set the Optimization
mode, see Changing
Controller Parameters - Cache tab.
The New Configuration Warning message box is displayed.
If the server and the controller displayed are not correct, click
Cancel to exit the New Configuration window and return
to the main window. Select the appropriate disk controller and reselect
New Configuration.
Proceed to add the next two disks so that three disks are displayed
in the lower list box. If you make a mistake or change your mind, select the drive from
the drives list and click Remove Disk.
NOTE: Because the logical drive has not been partitioned yet,
the Part Size (MB) and the Available Size (MB) are equal.
A single logical drive is considered to be a single partition. Note: Mixing SATA and FC disks to create a logical drive is
not supported.
This applies to all disks in this logical drive. In this example, the new logical drive is composed of three physical
disks, totaling 103428 Mbyte, as indicated in the Available Size
(MB) field. The maximum number of drives per logical drive for each RAID level
is: For RAID 1, note that if you select four or more drives, a logical
drive with a RAID 1+0 is created.
The Max Drive Size displays the total capacity of each disk.
A smaller logical drive can be created by decreasing this value. NOTE: If you do not change the Max Drive Size but you
do change the Partition Size, Sun StorEdge Configuration Service
creates a new partition at the specified partition size. The remaining
logical drive size capacity moves to the last partition. Remaining
capacity can be used later by expanding the drive (as explained in
Expanding a Logical Drive or Logical Volume). The drive capacity
is no longer editable after a partition is created.
Host channel connect to host computers either directly or indirectly
through switches or other devices. Select the appropriate host channel
based on the physical connection from the server to the array.
The ID is a unique address that identifies the logical drive to
the host.
NOTE: If you do not want to map the logical drive at this
time, select Do Not Map from the Channel list box.
Because logical drive initialization can take up to several hours,
you can choose to initialize a logical drive on-line. On-line initialization
enables you to begin configuring and using the logical drive before
initialization is complete. However, because the controller is building
the logical drive while performing I/O operations, initializing
a logical drive on-line requires more time than off-line initialization.
If you do not select On-line initialization, you can configure
and use the drive only after initialization is complete. Because
the controller is building the logical drive without having to also
perform I/O operations, off-line initialization requires less time
than on-line initialization.
NOTE:On-line Initialization does not apply to logical
volumes.
Select Default to assign the stripe size per Optimization
mode as specified in the default stripe size table shown in Changing
Controller Parameters - Cache tab, or select a different stripe
size.
Once the stripe size is selected and data is written to logical drives,
the only way to change the stripe size of an individual logical drive is
to back up all its data to another location, delete the logical drive, and
create a logical drive with the stripe size that you want.
CAUTION: Only change the stripe size after you have tested
the effects on your application.
The write policy determines when cached data is written to the
disk drives. The ability to hold data in cache while it is being
written to disk can increase storage device speed during sequential
reads. Write policy options include write-through and write-back.
Using write-through cache, the controller writes the data to the
disk drive before signaling the host OS that the process is complete.
Write-through cache has lower write operation and throughput performance
than write-back cache, but it is the safer strategy, with minimum
risk of data loss on power failure. Because a battery module is
installed, power is supplied to the data cached in memory and the
data can be written to disk when power is restored.
Using write-back cache, the controller receives the data to write
to disk, stores it in the memory buffer, and immediately sends the
host OS a signal that the write operation is complete, before the
data is actually written to the disk drive. Write-back caching improves
the performance of write operations and the throughput of the controller
card. Write-back cache is enabled by default.
NOTE: The setting you specify you specify in the Write Back
field on the Cache tab of the Change Controller Parameters window
is the default global cache setting for all logical drives. (See
Changing Controller
Parameters - Cache tab).
The array can be configured to dynamically switch write policy
from write-back cache to write-through cache if specified events
occur. Write policy is only automatically switched for logical
drives with write policy configured to “Default.” See
Peripheral Tab for more information about event trigger
operations.
NOTE: In this example, a total of 4000 Mbyte is shown for
the logical drive size as opposed to 6000 Mbyte; because this is a
RAID 5 level, you lose the capacity equal to 1 drive (2000
Mbyte) for parity.
NOTE: Do not partition a logical drive if you plan on adding
it to a logical volume. Once a logical drive is partitioned, it
cannot be added to a logical volume. To create multiple partitions of the same size, click Add Partition
as many times as partitions you want to create. You can also type
the partition size in the Part Size field and multiple (*)
it by the number of partitions you want to create, for example 100*128.
Any remaining Mbyte is added to the last partition. As you add partitions, the remaining capacity displayed in Available
Size (MB) decreases by the amount of the partition size.
When you click New LD, any available disks that haven't been
used are displayed. When the logical drive configuration for this array is complete,
click Commit, and then click OK. The completed configuration
is displayed. NOTE: You cannot change a logical drive configuration after
you click OK. NOTE: During initialization LD/LV size is displayed as 0 Mbyte.
NOTE: If you used System Administrator Manager (sam) to
unmount the file system, make sure it is closed before running the
ioscan command. To Create and Partition a Logical Volume A logical volume is composed of two or more logical drives. The logical volume can
be divided into a maximum of 32 partitions. During operation, the host sees a nonpartitioned logical volume or a partition of a logical volume as one single physical drive. NOTE: Logical volumes are unsuited to some modern configurations such as Sun Cluster environments, and do not work in those configurations. Use logical drives instead. NOTE: Do not partition the logical drive that you are adding
to the logical volume. A logical drive that has been partitioned cannot
be added to a logical volume.
The logical drive is added to the LV Definition box. The total
size of the logical volume is displayed in the Available Size (MB)
field. NOTE: Because the logical volume has not been partitioned
yet, the Part Size (MB) and the Available Size (MB)
are equal. A single logical volume is considered to be a single partition.
NOTE: Mixing SATA and FC logical drives to create a logical volume is not supported.
Repeat this step for every logical drive you want to ad to the logical
volume.
To create multiple partitions of the same size, click Add Partition
as many times as partitions you want to create. You can also type
he partition size in the Part Size field and multiply (*)
it by the number of partitions you want to create, for example 100*
128.
As you add partitions, the remaining capacity displayed in Available
Size (MB) decreases by the amount of the partition size.
When you have finished creating logical volumes and do not want to
create an individual logical drive, click Commit. NOTE: When you have finished creating logical volumes and
want to exit the New Configuration window, if you accidentally
click Commit LV instead of Commit, you still have to
create another logical drive; otherwise, you have to click Cancel
and configure the logical volume again.
NOTE: If you used System Administrator Manager (sam) to
unmount the file system, make sure it is closed before running the
ioscan command. To Clear a Configuration If at any time during the configuration process in the New Configuration window you are dissatisfied with the configuration, you can clear it. Sun StorEdge Configuration Service initializes the entire configuration on the selected array controller. NOTE: Host LUNs are automatically mapped after logical drives have completed the initialization process. |