McDATA StorageWorks 2/140 - Director Switch Planning Manual page 232

Physical Planning Considerations
5
Joining Zoned Fabrics
Factors to Consider
When Implementing
McDATA Products in a SAN Environment - Planning Manual
5-28
— The default zone is enabled or disabled separately from the
active zone set.
— If the default zone is enabled, then all devices not in a
specified zone are included in the default zone and can
communicate with each other.
— If the default zone is disabled and there is no active zone
set, then the zoning feature is completely disabled for the
fabric and no devices can communicate with each other.
— All devices are considered to be in the default zone if there is
no active zone set.
• RSCN service requests - registered state change notification
(RSCN) service requests are transmitted to all N_Ports or
NL_Ports attached to the director or switch when the zoning
configuration is changed.
• Broadcast frames - Class 3 broadcast frames are transmitted to all
N_Ports attached to the director or switch, regardless of zone
membership.
Directors and fabric switches are linked through ISLs to form
multiswitch fabrics. In a multiswitch fabric, the active zoning
configuration applies to the entire fabric. Any change to the
configuration applies to all directors and switches in the fabric.
When fabrics attempt to join, participating fabric elements exchange
active zone configurations and determine if their configurations are
compatible. If the configurations are compatible, the fabrics join. The
resulting configuration is a single zone set containing zone
definitions from each fabric. If the configurations cannot merge,
E_Ports that form the ISL for each fabric element become segmented.
The ports cannot transmit data frames between attached switches
(class 2 or 3 traffic) but can transmit control frames (class F traffic).
Zoning configurations are compatible if there are no duplicate
Domain_IDs, the active zone set name is the same for each fabric (or
switch in the fabric), and zones with the same names in each fabric
have identical members.
Consider the following factors when planning to implement zoning
for one or more directors or switches in the enterprise. In particular,
Zoning
consider the implications of zoning within a multiswitch fabric.