1. Administrator's Guide
  2. Library Management
  3. Using the Extended Store Feature

Using the Extended Store Feature

The following sections provide information about using the Extended Store Feature.

Note:

This feature does not apply to a single LSM without a pass-thru port.

When a cartridge is mounted, its “home location" is the storage cell from which it was mounted. Normally, when a cartridge is dismounted and its home location is in a different LSM than the drive, ACSLS attempts to assign a new home location in the closest LSM (the shortest pass-thru distance from the tape drive). This is called “floating" a cartridge to a new home location.

ACSLS attempts to return a cartridge to its home location after a dismount if that home location is in an LSM that is enabled for the Extended Store feature.

Note:

Events such as the volumes' home LSM being offline or a label mismatch on a dismount may prevent ACSLS from returning a cartridge to its home location. If such an event occurs, the cartridge is stored as close as possible to the LSM from which it was dismounted.

If you have an Extended Store LSM that you use for cartridge archive, this feature helps to ensure that cartridges from that LSM return to their home locations in that LSM. For example, if Extended Store LSM 3 is enabled for this feature and a cartridge from LSM 3 is mounted on a drive attached to LSM 1, after the cartridge is dismounted, ACSLS attempts to return the cartridge to its home location in LSM 3. If LSM 3 is not enabled, ACSLS tries to store the cartridge in a new cell in LSM 1.

You can only enable entire LSMs for this feature. You cannot enable LSM subcomponents, such as a panel or individual cell. To enable an entire ACS for this feature, you must enable each LSM in the ACS.

Note:

Enabling the Extended Store feature will increase pass-thru activity when cartridges are dismounted. This may significantly decrease library performance.

To enable an LSM for the Extended Store feature, modify the lsm_fixed_volume file (found in the $ACS_HOME/data/external/fixed_volume directory). After you modify the file, stop and restart ACSLS to enable the specified LSMs.

Use the following conventions when you modify the sample file:

  • Comment and blank lines are allowed throughout the file.

  • Each LSM identifier line consists of the ACS number, followed by a comma, followed by the LSM number. No spaces or tabs are allowed between the ACS number and the LSM number.

  • Each LSM identifier must be on a separate line.

  • No explicit ordering of the LSM identifier lines is required.

  • No explicit end-of-file delimiter is required

Example of the Extended Store Feature Control File: 

# This lsm_fixed_volume file must be found in the 
# $ACS_HOME/data/external/fixed_volume 
# directory. This is a sample lsm_fixed_volume file that may be  
# edited your particular configuration. 
# Comments may appear anywhere in this file, but must include a  
# pound sign in the first column. 
# Blanks lines are also allowed throughout the file for # readability, and 
# will be ignored. 
# For all the LSM identifiers found in this file, a “best" attempt  
# will be 
# made to return the volume to its home location at dismount. 
# A valid LSM identifier consists of the ACS number, separated bya comma, 
# and followed by the LSM number. Leading or trailing blanks are  
# ignored. 
#    ACS,LSM 
#    0,0 
#    0,1 
# ACS 1, LSM 0 through 3 
#    ACS,LSM 
#    1,0 
#    1,1 
#    1,2 
#   1,3

The following example is of a modified control file. In this example, the comment (#) character has been removed from the lines shown in bold to specify that LSMs 0,0 and 0,1 are enabled. 

# This lsm_fixed_volume file must be found in the  
# $ACS_HOME/data/external/fixed_volume 
# directory. This is a sample lsm_fixed_volume file that may be  
# edited your particular configuration. 
# Comments may appear anywhere in this file, but must include a  
# pound sign in the first column. 
# Blanks lines are also allowed throughout the file for  
# readability, and 
# will be ignored. 
# For all the LSM identifiers found in this file, a “best" attempt  
# will be 
# made to return the volume to its home location at dismount. 
# A valid LSM identifier consists of the ACS number, separated by a comma, 
# and followed by the LSM number. Leading or trailing blanks are  
# ignored. 
#     ACS,LSM 
      0,0 
      0,1 
# ACS 1, LSM 0 through 3 
#     ACS,LSM 
#     1,0 
#     1,1 
#     1,2 
#     1,3