User`s guide

Chapter 4. Implementing the SAN Data Gateway 297
A check mark will allow access, and as shown in Figure 4-28, you can see that
SAN connection 1 has access to SCSI channels 3 and 4, but not to SCSI
channels 1 and 2. SAN connection 4 has access to SCSI channels 1 and 2, but
not to SCSI channels 3 and 4. To change the settings, click any box and the
check mark will toggle on and off. All combinations are possible. Once the
desired settings are selected, click OK. For the new zone settings to take effect,
the SAN Data Gateway must be restarted.
4.5.2 Virtual Private SAN
The IBM Storage Area Network Data Gateway also provides LUN masking
through a feature called Virtual Private SAN (VPS). This provides a granular
restriction of host access to specific LUNs while utilizing and sharing the same
connectivity paths through the SAN Data Gateway.
VPS keeps track of Fibre Channel hosts by using their unique World Wide Name.
In this way, if a switch is attached, the Gateway will also keep track of it, because
the switch also has a unique World Wide Name. VPS also includes a host
registration service so that when a host is attached, its unique WWN is registered
to the Gateway to provide information on the host and its status.
Enabling VPS
The Virtual Private SAN feature has to be enabled, because it comes disabled
from the factory. To enable it, make sure the desired SAN Data Gateway is
highlighted, if more than one appears in your Specialist window. Select
Controls -> Feature Enable -> Virtual Private SAN, as shown in Figure 4-29.
Figure 4-29 Enabling Virtual Private SAN