The SL8500 and SL3000 support partitioning of their libraries.
One ACSLS server can manage multiple partitions in the same library.
SL8500 partitioning
SL8500 Complex Partitioning
The SL8500 8.3 and later firmware supports partitioning across a library complex. Up to 16 partitions can be created in a library complex of SL8500s connected by pass-thru ports.
ACSLS 8.3 and later releases support up to 16 partitions. ACSLS 8.2 and earlier releases support up to 8 partitions.
Enhanced SL8500 Partitioning (available with the SL8500 7.0x firmware)
With Enhanced SL8500 partitioning, only a single stand-alone SL8500 can be partitioned.
Enhanced SL8500 partitioning can support up to eight physical partitions.
Enhanced SL8500 partitioning is at the drive and cell array level.
Legacy SL8500 Partitioning
With Legacy SL8500 partitioning, only a single stand-alone SL8500 can be partitioned.
Legacy SL8500 partitioning can support up to four physical partitions.
Legacy SL8500 partitioning is at the rail (LSM) level, and a rail includes all licensed tape drives and cartridges on the rail.
A legacy SL8500 partition can include from one to four rails. The rails in a legacy SL8500 partition must be contiguous. For example, a partition can include rails 2, 3 and 4, but a partition cannot be just rails 2 and 4.
For more information on partitioning, refer to the SL8500 documentation set.
SL3000 partitioning
The SL3000 can support up to eight physical partitions.
The SL3000 can partition down to the drive and cell level.
For more information, refer to the SL3000 User's Guide.
Partitioning the SL8500 or SL3000 library provides the following capabilities:
ACSLS can manage open systems drives and cartridges, and HSC can manage mainframe drives and cartridges sharing the library.
More than one instance of ACSLS can access the library.
One instance of ACSLS can manage multiple partitions in the same library.
Provides protection and isolation of data cartridges in separate partitions.
A higher level of data organization.
An increase in user efficiency.
Caution:
You mustaudit a partitioned library after it is configured or reconfigured to ACSLS. The library reports the potential cell locations that are not accessible to ACSLS when ACSLS audits it. Inaccessible cell locations include: locations where CAPs, drives, and operator panels are installed; cell locations that the robots cannot access; cell locations that are not activated; and cell locations that are not in this partition.Caution:
If cells are reassigned from one partition to another, the cartridges in those cells will be orphaned, and will no longer be accessible by the partition that they were in before. The host managing the other partition could write over the data on the cartridges.Note:
Although the SL500 can be partitioned, ACSLS does not support partitioned SL500s.There are several steps that you must follow when you are partitioning a library. They are:
Plan your new configuration.
Schedule an outage to partition or re-partition a library.
When a library is re-partitioned, the library drops its communication to all hosts managing all partitions, even if their partitions are not affected by the change.
Note:
ACSAPI clients cannot be assigned to a physical partition of a library, just as they cannot be assigned to an ACS.Have your service representative license and enable partitioning on the SL8500 or SL3000.
Move cartridges from locations where they would not be accessible to locations that will still be in a partition managed by ACSLS.
Create your partitions using the SL Console.
Refer to the SL Console help for instructions.
Activate partitioning using ACSLS as described in "Partitioning a Library or Changing Partition IDs".
You must configure ACSLS to a partitioned library using acsss_config by specifying that the library is partitioned and entering the partition number.
Plan your new partitioned configuration ahead of time.
Organize the cartridges and drives for performance.
If you will do a lot of enters into and ejects from a partition, an SL8500 partition should include at least one of the bottom three rails. Partitions with few enters and ejects can be on the top rail.
When an SL8500 or SL3000 is partitioned or the partitions in an SL8500 or SL3000 are modified, access to your data is affected. Tape drives and cartridges that were managed by one host server may be managed by a different host.
Changes in configuration occur when a:
Library configuration has changed
Library has been re-partitioned and the partition managed by ACSLS has changed (a message is displayed)
Library capacity has changed and the cells reported as available to ACSLS have changed
When LSM Configuration or capacity have changed
When the configuration may have changed, you are notified by ACSLS Event Log and Event Notification messages.
The following procedures provided below ensure that outages are minimized, with continued access to your data. These procedures explain how to:
Partition an un-partitioned SL8500 or SL3000 into two or more partitions.
Modify the partitions in an SL8500 or SL3000 that is already partitioned.
Merge a partitioned SL8500 or SL3000 so it is a single, un-partitioned ACS.
The biggest challenges arise when: LSMs (SL8500 rails) are removed from a legacy SL8500 partition; or cells and drives are removed from an SL3000 or enhanced SL8500 partition.
Refer to the procedures for "Moving Cartridges Before Removing Cells from a Partition" for details.
These procedures describe how to partition an un-partitioned library or to change partition IDs on an existing partitioned library.
Move the cartridges before removing an SL8500 LSM or SL3000 or SL8500 cells from an ACS.
If ACSLS manages one of the partitions in the new library configuration, follow the procedures for "Creating the Volume List File" or "Moving Cartridges Before Removing Cells from a Partition" to move the cartridges off of LSMs that will be assigned to another partition.
Quiesce the library before re-partitioning it, and vary the ACS(s) and port(s) offline.
Partition the library using the SL Console.
The following occurs after you press <Apply>. The library:
Rejects any new requests from ACSLS.
Drops all host connections.
Applies partitioning changes.
Accepts new host connections.
Reconfigure ACSLS to activate the partition changes.
Because the library was partitioned for the first time, or it was re-partitioned and the partition ID changed, ACSLS cannot reconnect to the library. In order to reconnect, follow the procedure below:
Bring down ACSLS: acsss disable.
Run acsss_config to configure the ACS and select Option 8.
Reply y (yes) when asked if the ACS is a partitioned library. After replying y (yes), enter the partition number. Refer to "Setting CSI Tuning Variables" for more information.
Start ACSLS with the new configuration: acsss enable
Vary the port(s) online and ACS(s) to diagnostic mode.
Audit the ACS(s).
Vary the ACS(s) online.
These procedures describe how to re-partition an existing partitioned library.
Move the cartridges before removing an LSM or cells from an ACS.
If ACSLS manages one of the partitions in the new library configuration, follow the procedures for "Creating the Volume List File" or "Moving Cartridges Before Removing Cells from a Partition" to move the cartridges off of LSMs that will be assigned to another partition.
Quiesce the library before re-partitioning it, and vary the ACS(s) and port(s) offline.
This causes ACSLS to reject new requests from clients while the ACS(s) remain available for dynamic reconfiguration (after the re-partition).
Re-partition the library using the SL Console.
The following then occurs after you press Apply. The library:
Rejects any new requests from ACSLS.
Drops all host connections.
Applies partitioning changes.
Accepts new host connections.
Reconfigure ACSLS to activate the partition changes.
Note:
There may be no changes to a specific partition. The changes may only affect other partitions. In this case, no ACSLS configuration changes are needed.Note:
Because the library was not partitioned the first time or it was re-partitioned and the partition ID did not change, ACSLS can reconnect to the library.Select one of the following:
Run Dynamic Config (config acs acs_id) while ACSLS is running. This updates the ACSLS configuration to match the new library configuration. Follow this procedure:
Vary the port(s) online.
Update the ACS(s) configuration with config acs acs_id.
Or, bring down ACSLS and run acsss_config (option 8) to update the partition configuration in ACSLS. Follow this procedure:
Bring down ACSLS: acsss disable
Update the configuration using acsss_config.
Restart ACSLS: acsss enable.
Vary the port(s) online.
Vary the ACS(s) to diagnostic mode.
Audit the ACS(s).
Vary the ACS(s) online.
Optionally, eject cartridges from the partition(s) managed by ACSLS.
If ACSLS will not be managing the non-partitioned library, you may want to eject cartridges from the partition(s) managed by ACSLS. This enables you to enter them into other ACS(s) that ACSLS manages.
You can use the ejecting.sh utility for ejecting multiple cartridges.
Quiesce the library before re-partitioning it, and vary the ACS(s) and port(s) offline.
Re-partition the library using the SL Console.
The following then occurs after you press Apply. The library:
Rejects any new requests from ACSLS.
Drops all host connections.
Applies partitioning changes.
Accepts new host connections.
Reconfigure ACSLS to change the ACS to an un-partitioned library or to remove this ACS (partition) from its configuration.
Because the library was changed from partitioned to un-partitioned, ACSLS cannot reconnect to the library. In order to reconnect, follow the procedure below:
Bring down ACSLS: acsss disable
Run acsss_config to configure the ACS.
Reply n (no) when asked if the ACS is a partitioned library. Refer to "Setting CSI Tuning Variables" for more information.
Start ACSLS with the new configuration: acsss enable.
Vary the port(s) and ACSs online.
To view the partition ID(s) for one or more ACSs, use one of the following commands:
query lmu all for all ACSs
query lmu acs_id for a single ACS
Output Example:
ACSSA> q lmu 0
2008-02-27 06:08:02
ACS: 0 Mode: Single LMU Active Status: Not Comm
Not Partitioned Standby Status: -
ACS State Desired State
offline online
Port Port State Desired State Role CL Port Name0, 0 offline online - 13 172.27.2.6
This section discusses CAP behavior.
WARNING:
All ACSs must have one CAP that is dedicated or is shared. Because all of the CAPs in an SL3000 can be dedicated to other partitions, this is a crucial restriction when configuring SL3000 partitions.
With an SL3000 library, a CAP can be dedicated to a partition. When CAPs are dedicated to a partition, ACSLS can set these CAPs to automatic mode.
In an SL8500 library with legacy partitioning, CAPs are always shared among all partitions.
In a partitioned SL3000, or SL8500 with enhanced partitioning, library CAPs can be shared between partitions. The process is as follows:
When a host uses a CAP to enter or eject cartridges, it reserves the CAP for its exclusive use.
The host must complete the enter or eject and leave the CAP empty and closed.
If you must terminate an enter on either of the following:
ACSLS - the canceled enter command must be issued
HSC - the drain command must be issued
The CAP is now available for use by any partition in the library.
If a host does not complete the enter or eject, the CAP may still contain cartridges for the affected partition. The CAP is still in a reserved status. This causes problems when other partitions need to use the CAP. To resolve this, the library must identity the host holding the reserve and terminate the enter or eject from that host.
In rare cases, you may not be able to access the host holding the reservation, either because the host crashed and cannot be restarted, or you lack physical access or the security authority to issue the commands needed. In these cases, the CAP reservation can be overridden using the SL Console.
Caution:
Overriding a CAP reservation using the SL Console should be done only as a last resort.ACSLS can manage multiple partitions in the same library, and these partitions can share the same CAP(s). Audit ejects all cartridges with a duplicate and unreadable vol_id. When you audit multiple partitions (ACSs) at the same time, the audits may try to use the same shared CAP to eject the cartridges. The first audit reserves the CAP and the other audits are unable to reserve the CAP. The later audits are then unable to eject the cartridges.
To prevent this from happening, set the CAP priorities so different shared CAPs are the highest priority CAP in the different partitions. For example, if partitions 2 and 3 in an SL3000 are sharing CAPs 5 and 6, set CAP 5 as the highest priority CAP in partition 2 and CAP 6 as the highest priority CAP in partition 3.
Consider the following when reserving the CAP:
When a CAP is in use for an enter or eject operation, all 39 slots (SL8500) and 26 slots (SL3000) are reserved for that operation. The CAP cannot be subdivided.
For addressing purposes, the CAP needs a location (ACS,LSM,CAP#). The LSM number is associated with the second rail in each library. For example: ACS#,1,0 for CAP A and ACS#,1,1 for CAP B
Reserving the CAP
The CAP is a common component among partitions. Each host will:
reserve the CAP to use it for an enter or eject.
release the CAP when the enter or eject is terminated. Another host can then use it.
When ACSLS finds that a CAP is reserved by another partition, it reports the partition ID and host ID holding the reservation.
Contact the host owning the reserved CAP and request for them to complete the enter or eject.
Once this is done, the empty CAP is then unreserved and available.
If the CAP reservation cannot be released by the host holding it, the SL Console (SLC) command overrides the CAP reservation.
The SLC command displays a warning to the host informing it that the reservation from the specific partition owner will be removed.
The SL Console queries the CAP to find the partition owner/requester/reserver.
The SLC displays the partition name (HLI1, HLI2, HLI3, HLI4, or Default) in the warning.
The library sends a CAP Overridden Message to the host that held the reservation.
This host should terminate the enter or eject task that was in progress.
The library now owns the CAP.
The CAP must be empty and closed before it is available to be used by another host. If the:
CAP has cartridges in it, you must empty the CAP before a partition can use it using the SL Console.
CAP is open, you must empty and close it. The library can then audit it and ensure that it is empty. Until the CAP is closed, it cannot be made available to any partitions.
CAP is empty, it will be locked and available to be reserved by any partition.
The CAP is now unreserved and is available for use by any partition.
An SL3000 can partition down to the drive and cell level, and an SL8500 with enhanced partitioning can partition to the drive and cell array level. If cells are reassigned from one partition to another, the cartridges in these cells are orphaned, and are no longer accessible by the partition that they were in before. The host managing the other partition could then write over the data on these cartridges.
To prevent cartridges from being orphaned when partition boundaries change, and before you re-partition the library, move the cartridges to cells that will remain in the partition.
Since SL3000 is a single LSM, the existing ACSLS move command does not work. The cartridges would be moved somewhere else in the library, and may be moved to another cell that will also be removed from the partition. To handle this, the move command provides the ability to move cartridges to a specific cell.
The syntax for moving cartridges to a cell is like moving them to an LSM. However, instead of specifying an LSM ID, you specify a cell ID, as follows:
a=acs, l=lsm, p=panel, r=row, and c=column
move AAAAAA a,l,p,r,c (for a cell move)
move AAAAAA a,l (for a standard LSM move)
Example for a cell move:
move EDU010 0,1,0,5,1
Note:
You can use thedisplay command to display a list of available (empty) cells in a specified panel: display cell a,l,p,*,* -status empty -f status