Fabric OS Administrator's Guide v6.4.0 (53-1001763-01, June 2010)

Fabric OS Administrator’s Guide 243
53-1001763-01
Zoning overview
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Session-based hardware enforcement is in effect in the following cases, on a per-zone basis:
• A zone does not have either all WWN or all D,I entries.
• Overlapping zones (in which zone members appear in two or more zones).
Identifying the enforced zone type
1. Connect to the switch and log in as admin.
2. Enter the portZoneShow command, using the following syntax:
portzoneshow
Considerations for zoning architecture
Table 50 lists considerations for zoning architecture.
Zoning can be implemented and administered from any switch in the fabric, although it is
recommended that you use a switch running the latest Fabric OS version. If the switch is running
Fabric OS v6.0.x or earlier, it must have an Advanced Zoning license enabled.
The zone configuration is managed on a fabric basis. When a change in the configuration is saved,
enabled, or disabled according to the transactional model, it is automatically (by closing the
transaction) distributed to all switches in the fabric, preventing a single point of failure for zone
information.
NOTE
Zoning commands make changes that affect the entire fabric. When executing fabric-level
configuration tasks, allow time for the changes to propagate across the fabric before executing any
subsequent commands. For a large fabric, you should wait several minutes between commands.
TABLE 50 Considerations for zoning architecture
Item Description
Type of zoning
enforcement: frame-
or session-based
If security is a priority, frame-based hardware enforcement is recommended.
Use of aliases The use of aliases is optional with zoning. Using aliases requires structure when defining
zones. Aliases aid administrators of zoned fabrics in understanding the structure and
context.
Interoperability mode See Chapter 14, “Interoperability for Merged SANs,” for interoperability mode
considerations when using zoning.
Effect of changes in a
production fabric
Zone changes in a production fabric can result in a disruption of I/O under conditions
when an RSCN is issued because of the zone change and the HBA is unable to process the
RSCN fast enough. Although RSCNs are a normal part of a functioning SAN, the pause in
I/O might not be acceptable. For these reasons, you should perform zone changes only
when the resulting behavior is predictable and acceptable. Ensuring that the HBA drivers
are current can shorten the response time in relation to the RSCN.
Testing Before implementing a new zone, you should run the Zone Analyzer from Web Tools to
isolate any possible problems. This is especially useful as fabrics increase in size.
Confirming operation After changing or enabling a zone configuration, you should confirm that the nodes and
storage can identify and access one another. Depending on the platform, you might need
to reboot one or more nodes in the fabric with the new changes.