McDATA StorageWorks 2/140 - Director Switch Planning Manual page 158

Implementing SAN Internetworking Solutions
4
Routed SAN Zoning
McDATA Products in a SAN Environment - Planning Manual
4-16
There is only one router fabric manager per fabric. If more than one
R_Port (from the same or multiple routers) connects to a fabric, then
the port with the lowest worldwide name (WWN) is elected router
fabric manager for that fabric. Other R_Ports become subordinate
ports. All R_Ports (router fabric manager or not) participate in FSPF
routing protocol and traffic forwarding.
SAN Routing provides flexibility with respect to zoning behavior and
interactions between a router and attached fabrics. The zone policy
(set at the Fabrics tab of the Fabric Configuration dialog box) specifies
how zoning information is synchronized between the router and
fabrics. It is not a requirement that all router-attached fabrics use the
same zone policy. The zone policy options are:
• No Zone Synchronization - Device zoning is controlled at the
fabric level through a Fibre Channel SAN management
application. Zone configurations propagated from a SAN router
to a fabric are negated through a SAN management application.
• Append IPS Zones - Device zoning control is shared between a
SAN router (SANvergence Manager application) and a Fibre
Channel SAN management application. Existing zones
configured at the fabric level are synchronized through the
SANvergence Manager application.
No Zone Synchronization
When the zone policy is set to No Zone Synchronization, zone set
information between a SAN router and the associated fabrics is not
synchronized. In an environment with configured Fibre Channel
fabrics (prior to enabling SAN routing), it may be preferable to use
the existing SAN management application to enforce zoning. This
practice is applicable if all devices are fabric-attached and no devices
are directly attached to SAN router ports. A typical application for
this zone policy is remote data replication (RDR), where a small
number of devices must communicate across fabric boundaries.
Using a SAN management application, matching zones are created in
each fabric for all devices that require cross-fabric communication.
This implies that two devices that need to communicate are
configured in a common zone in both fabrics. At the SANvergence
Manager application, one zone is created that contains all devices that
are shared across the fabrics. Shared devices are visible to both fabrics
through standard SW_RSCNs.