1. Administrator's Guide
  2. Database Administration
  3. Migrating mchangers for Fibre to a New Platform

Migrating mchangers for Fibre to a New Platform

The SCSI Media Changer (mchanger) is the Fibre attached library device driver that communicates between ACSLS and any Fibre attached library. A mchanger must be created for each Fibre attached library that is connected to ACSLS.

The numbers in /dev/mchanger# device driver links may change when importing ACSLS to another platform and/or release which can create problems. For example, an SL500 or SL150 library that was connected through /dev/mchanger3 on the old ACSLS server may be connected through /dev/mchanger4 on the new ACSLS server.

This is not an issue when going from one ACSLS Linux server to a new Linux server because the format of mchanger names is different on Linux. Instead of a number, on Linux servers, the mchanger name includes the library serial number.

The following procedure avoids problems when you have media changer drivers configured for Fibre-attached libraries and migrate to a new ACSLS release or server platform.

  1. On a Solaris or AIX ACSLS server, record the mchanger number associated with each Fibre-attached library on the old ACSLS server. See Record Details about Fibre-attached Libraries on the Old ACSLS Server.
  2. Update your configuration with the new mchanger names for the libraries. See Reconfigure ACSLS to Change mchanger Names for Fibre-attached Libraries.

Record Details about Fibre-attached Libraries on the Old ACSLS Server

On a Solaris or AIX ACSLS server, before exporting the database from the old ACSLS server, record the mchanger number associated with each Fibre-attached library on the old ACSLS server. Save the output from cmd_proc and the showDevs.sh utility that shows the mchanger associated with each Fibre-attached ACS and the serial numbers of the libraries. 

cmd_proc:

  • query lmu all

    This shows all ACSs controlled by ACSLS and their port connections. The port names for Fibre-attached libraries on Solaris and AIX systems will be /dev/mchanger#, where # is a number

  • display lsm * -f type serial_num

    This displays the library type and serial number of all LSMs managed by ACSLS. Use library type, such as SL500 or SL150, to identify the Fibre-attached libraries. Use the serial number to identify the specific library.

Utilities: 

showDevs.sh -s

The showDevs.sh utility with the –s option shows the mchanger device link, the library type, the library serial number, and details which identify the Fibre-attached library.

Reconfigure ACSLS to Change mchanger Names for Fibre-attached Libraries

After importing your database, if you are either migrating to or from Linux, or the same mchanger numbers were not configured on Solaris, you must update your configuration with the new mchanger names for these libraries.

Using acsss_config:

  1. Log in as acsss.
  2. Use showDevs.sh to display all of your Fibre-attached libraries.

    The showDevs.sh utility with the –s option shows the mchanger device link, the library type, the library serial number, and details which identify the Fibre-attached library.

  3. Save the output from showDevs.sh in a file so you can copy and paste it into prompts from acsss_config.
  4. With the output from showDevs.sh -s displayed in one terminal window, open a second terminal window and log in as acsss.
  5. Run acsss_config in the second terminal window.
  6. Select Option 8: Define or Change Library Configuration.
  7. Reply y to Configure library communications? (y/n):
  8. Reply y to Library server data base exists and will be overwritten, continue (y or n)?
  9. Referencing the saved output from query lmu all, reconfigure all of the ACSs that were configured on your old ACSLS server.
    1. Configure all of the ACSs in the same order, and with the same ACS numbers as they were on the old ACSLS server.
    2. Configure the non Fibre-attached libraries as partitioned or not partitioned, and with the same port connections as they had on the old ACSLS server.
  10. When configuring the port connections for your Fibre-attached libraries, specify the new mchanger link names used on the new ACSLS server. For mchanger link names on Linux, the easy way to do this is copy them from the showDevs.sh output and paste them after the acsss_config prompt.
  11. Finish reconfiguring your ACSLS library hardware.