IBM E16RMLL-I - Tivoli Storage Manager, Implementation Manual

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IBM Tivoli Storage Manager Implementation Guide
ANR0403I Session 333 ended for node DIOMEDE (WinNT).
ANR0403I Session 334 ended for node DIOMEDE (WinNT).
ANR0403I Session 332 ended for node DIOMEDE (WinNT).
Alternatively, you may use the following command to figure out whether the data
movement was LAN-free:
query actlog search=storage_agent_name msgno=8337
Last but not least, from the Tivoli Storage Manager client, the detailed status
report after each client operation also shows you the amount of LAN-free data
transferred. If the client operation failed to use the LAN-free path then the
LAN-free Data Bytes information is grayed out in the GUI status window or the
value for the respective statistic item is zero in backup-archive CLI.
16.6.2 LAN-free data transfer considerations
Tivoli Storage Manager LAN-free data transfer provides an effective means to
off-load backup-archive data traffic from your LAN to the SAN. LAN-free data
transfer improves performance especially when backing up large files, typically
larger than 50 MB.
Therefore, we recommend that you use LAN-free transfer to back up large
databases and file system images because there is a significant performance
improvement. This also allows you to fully utilize your LAN for other application
and communication processing.
On the other hand, there are instances where LAN data transfer may be faster
than LAN-free data transfer, particularly when backing up many small-size files.
Traditional incremental backups where only a small amount of the data has
changed usually perform better over the LAN than LAN-free, since this type of
operation usually does not allow a tape drive to operate at streaming speeds.
To ensure better performance, you must consider the following items:
򐂰 The hardware speeds of the LAN-based hardware versus the SAN-based
hardware
򐂰
The topology configured, and whether bandwidth is shared or dedicated
򐂰 The average size of the files being transferred
16.7 Summary
This chapter has demonstrated the configuration of the LAN-free feature in a
Tivoli Storage Manager environment. We have provided implementation details