Changes in TSM SANDISCOVERY server option from v6.2

SANDISCOVERY is the TSM server option which is used to scan the devices attached to TSM server which can be used for TSM Lanfree backups. The behaviour for the SANDISCOVERY option has changed for IBM Tivoli Storage Manager server levels 5.5.3, 6.1.2, and later releases. These changes might produce errors for your environment, depending on the values you have set for the option.

The behaviour of the original OFF option was changed in 5.5.3 and 6.1.2 releases. With the changes in behaviour, the OFF option will still disable the SAN discovery function. But the server will also take a device path offline and the ANR8873E message will be issued if it is unable to open this device.

A new option, PASSIVE, was introduced in 5.5.3 and 6.1.2 releases. With this option specified, the server will disable the SAN discovery function, but will not take a device path offline if the server is unable to open it. The behaviour for the PASSIVE option is same as the behavior for the OFF option in levels prior to 5.5.3, and 6.1.2 releases.

• The server will issue a new message when the PASSIVE option is used in the dsmserv.opt, or when you try to change the current SANDISCOVERY option to PASSIVE during run time. This new message will recommend that the option be set to OFF for equivalent functionality. Here is an example of the new message:

ANR0135W The SANDISCOVERY option is set to PASSIVE. Please use the OFF option for the same SAN discovery functionality

• A new option, UNSCANNEDPATHOFF, will be introduced in 5.4.6, 5.5.4, 6.1.3, and later releases for SANDISCOVERY. This option has the same function that the OFF option has in 5.5.3 and 6.1.2 releases. It means a device path might be taken offline if the server is unable to open it.

SANDISCOVERY Changes from TSMv6.2

The SANDISCOVERY option specifies whether the Tivoli Storage Manager SAN discovery function is enabled. To use SAN discovery, all devices on the SAN must have a unique device serial number. When set to ON, the server performs SAN discovery in the following instances

• When the device path has been changed.

• When the QUERY SAN command is issued

Using SAN discovery, the server can automatically correct the device's special file name if it has been changed for a specified tape device.

Also Read: Installation & Configuration of TSM Storage Agent (Lanfree Backup)

The Tivoli Storage Manager server does not require persistent binding with the SAN discovery function enabled. To display a list of devices seen by the server, you can issue the QUERY SAN command.

Syntax

                 .-ON---------------.   

>>-SANDISCOVERY--+-OFF--------------+--------------------------><

                 '-UNSCANNEDPATHOFF-'   

Parameters

ON
Specifies that the server performs SAN discovery when the device path has been changed, or when the QUERY SAN command is issued. 

OFF
Specifies that the server does not perform SAN discovery when the device path has been changed, or when the QUERY SAN command is issued.

UNSCANNEDPATHOFF
Specifies that the server does not perform SAN discovery when the device path has been changed, or when the QUERY SAN command is issued. This conceals the message that is produced when you disable SAN discovery and does not take device paths off-line.