How to achieve over 2 TB/hr network backup with Integrity entry-class servers running HP-UX 11i v3

Tape library and device considerations

The HP StorageWorks ESL 712e tape library accommodates a variety of SAN topologies for

configuration. For switched FC connections of tape devices to the backup server, use the

management interface to ensure that the tape drive port settings are set to “Fabric” for each of the

tape devices. In the test configuration, two tape devices were initially configured erroneously as

“loop”, which negatively affected overall throughput to the device.

The tape library management interface is also useful for displaying the WW port names and the LUN

WWID associated with each tape drive and library robotic device. This information helps you

determine the DSF or Logical Device Name configured for the device in the backup utility.

Balancing backup data streams

Backup utilities usually provide an option for auto-balancing of all clients’ backup data streams across

the available backup devices and media. Some backup utilities’ auto-balancing algorithms might

spread data streams from a specific client across multiple backup devices and media, making data

recovery slower and more complex, requiring multiple units of backup media to complete. For faster

and less complex recovery, HP recommends making the additional effort to (1) verify that each client’s

data is not being undesirably spread across multiple backup devices and media, and if necessary, (2)

to manually segment and balance the client backup data streams to be more appropriate for quick

restore. Optimal recovery of data is most essential for enabling business continuity and continued

accessibility to your critical data.

Also, consider making post-backup copies of each client’s backup data for collocation of client data

on a single unit of media, enabling a much less complex recovery operation when required. This is

especially important for the most business-critical application servers, as recovery of these servers must

happen as quickly as possible.

Private backup network considerations

In real customer environments, network-based backup and restore of client data is often performed

over the primary, shared network. During this characterization effort, the backup and restore

operations were performed over a private, dedicated 1GbE network to prevent the results from being

skewed by traffic congestion that might occur over a shared network.

Backup utilities are designed and optimized for use over the systems’ primary network connection, as

most systems appropriate for network backup typically have only one network port. With client

configurations for network backup, backup utilities typically resolve to the shared, primary network of

the client. For backup operations, these configurations usually use the first network link associated

with that client’s host name, unless specifically overridden. While most backup utilities provide

configuration capability to perform backup and recovery over alternate (non-primary) network

connections, additional manual configuration changes are typically required. For example, you might

need to add the private network client and backup server IP names to the /etc/hosts file, and

create or modify the /etc/nsswitch.conf file to include search of files and use of a DNS server

or other IP name resolution options (if DNS service is unavailable on the private network).

For use of the private network, Data Protector requires that you manually edit the cell_server

(/etc/opt/omni/client/cell_server) configuration file on each client to reflect the private

network name for the backup server. This enables backup data from clients to be sent over the private

network to the backup server. Restore operations over a private network do not require additional

configuration changes.