A direct attach topology is implemented by connecting the HP StoreOnce Backup System directly
to a Host Bus Adapter (HBA). In this configuration the Fibre Channel private loop protocol must
be used.
The preferred topology for the HP StoreOnce Backup System is switched fabric using NPIV (N_Port
ID Virtualisation).
NOTE:
Please refer to
http://www.hp.com/go/connect
or
http://www.hp.com/go/ebs
for the
latest information.
Zoning
Zoning is only required if a switched fabric topology is used.
Due to complexities in multi-hosting tape devices on SANs, it is best to make use of zoning tools
to help keep the backup/restore environment simple and less susceptible to the effects of changing
or problematic SANs.
Zoning provides a way for servers, disk arrays, and tape libraries to see only those hosts and
targets that they need to see and use. The benefits of zoning include but are not limited to:
•
Limiting unnecessary discoveries on the HP StoreOnce Backup System
•
Reducing stress on the HP StoreOnce Backup System and its library devices by polling agents
•
Reducing the time it takes to debug and resolve anomalies in the backup/restore environment
•
Reducing the potential for conflict with untested third-party products
Zoning may not always be required for configurations that are already small or simple. Typically
the bigger the SAN is, the more zoning is needed. HP recommends the following for determining
how and when to use zoning.
•
Small fabric (16 ports or less)—may not need zoning.
•
Small to medium fabric (16 - 128 ports)—use host-centric zoning. Host-centric zoning is
implemented by creating a specific zone for each server or host, and adding only those storage
elements to be utilized by that host. Host-centric zoning prevents a server from detecting any
other devices on the SAN or including other servers, and it simplifies the device discovery
process.
•
Disk and tape on the same pair of HBAs is supported along with the coexistence of array
multipath software (no multipath to tape or library devices on the HP StoreOnce Backup System,
but coexistence of the multipath software and tape devices).
•
Large fabric (128 ports or more)—use host-centric zoning and split disk and tape targets.
Splitting disk and tape targets into separate zones will help to keep the HP StoreOnce Backup
System free from discovering disk controllers which it doesn't need to see. For optimal
performance, where practical, dedicate HBAs for disk and tape.
NOTE:
Overlapping zones are supported.
VTL devices on an Ethernet network (not HP B6000)
Each emulated backup device is uniquely mapped to an individual host; this is the network server
or PC that you wish to back up.
•
The backup device appears to the host as a locally-attached tape autoloader or library.
•
The backup device is accessed and managed from the backup software running on the host.
•
The backup device is not visible to other devices on the network.
•
Multiple servers may not back up to a single backup device.
14
Virtual Tape Devices