Overview

There are multiple options for connecting ACSLS to SL8500 and SL3000 libraries. These options can be used independently or together, for communication between ACSLS and an SL8500, or SL3000.

In a string of connected SL8500s, you can implement Dual TCP/IP and/or Multi-library TCP/IP, and/or Redundant Electronics.

In an SL3000 or SL8500, you can implement Dual TCP/IP and/or Redundant Electronics (RE). You can connect to an SL3000 or SL8500 through IPv4.

The following summarizes the connections options:

• Dual TCP/IP

  Dual TCP/IP provides two separate and independent TCP/IP connections between ACSLS and a Library Controller card. If one of these communication paths fail, ACSLS automatically uses the second path for communication.

  To implement Dual TCP/IP support, routing tables on both the ACSLS server and the library must be defined and managed using the “route" command. These routing tables force communication between a pair of ports on the ACSLS server and the library to use a defined network communication path.

  Both the SL8500 and the SL3000 support Dual TCP/IP communication with the library.

• Multi TCP/IP Support

  Multi TCP/IP support allows the ACSLS server to connect to multiple SL8500 libraries in a string of connected SL8500s. If communication with one library fails, ACSLS automatically sends library communication to the connections with the other libraries. The libraries automatically forward the messages to the other libraries.

  Configuring and managing Multi TCP/IP communication is simpler than Dual TCP/IP because routing tables do not need to be defined on the ACSLS server or the SL8500 libraries. However, Multi TCP/IP requires a string of connected SL8500 libraries. It does not apply to single, stand-alone SL8500 or SL3000 libraries.

• Redundant Electronics (RE)

  RE uses a redundant set of Library Controller cards. At any given time, one set is active and the other set is standby. The active Library Controller can failover to the standby in response to a command from ACSLS or the SL Console. Automatic failover can be initiated by the library if a library card fails.

  RE enables minimally disruptive library firmware (microcode) downloads. Within a string of connected SL8500s, RE can be implemented on a per library basis. You can implement RE in any or all libraries within a complex.

  To support RE in the library, ACSLS 7.3.1 or 8.0.2 or later is required.

Displaying the status of ACSLS Communication with Libraries

Use the query lmu command to view and monitor the status of ACSLS communication with the libraries it manages. The query lmu command also shows the status of ACSs and port connections to libraries.