User`s guide

Chapter 4. Implementing the SAN Data Gateway 307
SAN connection 1 has access to the LUNs on SCSI channels 2 and 4. VPS will
control access to LUNs on SCSI channels 2 and 4 for SAN connection 1. Since
SAN 1 is not zoned for SCSI channel 1 and 3, it will not reach any LUNs on these
channels. Even, if a LUN on SCSI 3 has been enabled for access to a host on
SAN 1 in the VPS settings window, the host will not see that LUN because of the
zoned settings. The same is true for SAN
connection 4. A host connected here will access LUNs only on SCSI channels 1,
2, and 3, but not channel 4, regardless of whether the VPS settings will allow it.
4.6 Adding Fibre Channel fabric components
The SAN Data Gateway is an integral component in a storage network. As such,
you can also attach other SAN fabric components to the Gateway to increase the
connectivity options in a SAN. Hubs and switches can be easily added, and allow
many more systems, local or remote, to access the SCSI devices on the
Gateway.
As switches provide more flexibility, and hubs are mainly used to extend
distances, the following discussion will focus on switch implementation, rather
than hubs.
4.6.1 Connecting an IBM SAN Fibre Channel Switch
The IBM SAN Fibre Channel Switch provides either an 8 port or 16 port switch
that can also be cascaded.
Allowing fabric connection
Before connecting a switch to the SAN Data Gateway, there is a setting that must
be checked to allow proper fabric connection. From the SAN Data Gateway
Specialist, select the Fibre Channel port that will have the switch connected.
Select Control -> Fibre Channel, and the Set Fibre Channel Parameters
window appears, as shown in Figure 4-40.