Best Practices For Zoning; Broadcast Zones - HP A7533A - Brocade 4Gb SAN Switch Base Administrator's Manual

Table 88 Considerations for zoning architecture (continued)
Item
Effect of changes in
a production fabric
Confirming
operation
The zone configuration is managed on a fabric basis. Zoning can be implemented and administered from
any switch in the fabric (it is best to use a newer switch such as the SAN Switch 4/32B, 4/64 SAN Switch,
or a Director) that has an Advanced Zoning license enabled. 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.

Best practices for zoning

The following are recommendations for using zoning:
• Always zone using the highest Fabric OS-level switch.
Switches with lower Fabric OS versions do not have the capability to view all the functionality that a
newer Fabric OS provides, as functionality is backwards compatible but not forwards compatible.
• Zone using the core switch versus an edge switch.
• Zone using a Director over a switch.
A Director has more resources to handle zoning changes and implementations.

Broadcast zones

Fibre Channel allows sending broadcast frames to all Nx_Ports if the frame is sent to a broadcast
well-known address (FFFFFF); however, many target devices and HBAs cannot handle broadcast frames. To
control which devices receive broadcast frames, you can create a special zone, called a broadcast zone,
which restricts broadcast packets to only those devices that are members of the broadcast zone.
If there are no broadcast zones or if a broadcast zone is defined but not enabled, broadcast frames are
not forwarded to any F_Ports. If a broadcast zone is enabled, broadcast frames are delivered only to those
logged-in Nx_Ports that are members of the broadcast zone and are also in the same zone (regular zone)
as the sender of the broadcast packet.
Devices that are not members of the broadcast zone can send broadcast packets, even though they cannot
receive them.
A broadcast zone can have domain,port, WWN, and alias members.
Broadcast zones do not function in the same way as other zones. A broadcast zone does not allow access
within its members in any way. If you want to allow or restrict access between any devices, you must create
regular zones for that purpose. If two devices are not part of a regular zone, they cannot exchange
broadcast or unicast packets.
Description
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.
Changing HBA drivers can shorten the response time in relation to the
RSCN.
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.
Fabric OS 6.x administrator guide 391