Brocade Communications Systems 53-1001763-02 manual AD255

Fabric OS Administrator’s Guide 339
53-1001763-02
Administrative Domains overview 15
Initially, the AD0 implicit membership list contains all devices, switch ports, and switches in the
fabric. When you explicitly create AD1 through AD254, the devices, switch ports, and switches
used to create these user-defined Admin Domains disappear from the AD0 implicit
membership list.
•The explicit membership list contains all devices, switch ports, and switches that you explicitly
add to AD0 and can be used to force device and switch sharing between AD0 and other Admin
Domains.
AD0 can be managed like any user-defined Admin Domain. The only difference between AD0 and
user-defined Admin Domains is the implicit membership list.
The implicit members of AD0 change dynamically as the membership of other Admin Domains
changes. The explicit members of AD0 are not deleted unless you explicitly remove them.
For example, if you explicitly add DeviceA to AD0 and it is not a member of any other Admin
Domain, then DeviceA is both an implicit and an explicit member of AD0. If you add DeviceA to AD2,
then DeviceA is deleted from the AD0 implicit membership list, but is not deleted from the AD0
explicit membership list. If you then remove DeviceA from AD2, DeviceA is added back to the AD0
implicit membership list (assuming DeviceA is not in any other Admin Domain).
When a new device is added to the fabric, it automatically becomes an implicit member of AD0
until it is explicitly added to an Admin Domain.
AD0 is useful when you create Admin Domains because you can see which devices, switch ports,
and switches are not yet assigned to any Admin Domains.
AD0 owns the root zone database (legacy zone database).
AD255
AD255 is used for Admin Domain management. You can use AD255 to get an unfiltered view of the
fabric and to view the hierarchical zone databases of AD0 through AD254. All Admin Domain
management is done in the AD255 context.
AD255 does not have a zone database associated with it; you cannot use AD255 to perform any
zoning management tasks (non-read operations such as creating or modifying zones).
Figure 53 on page 340 shows the same fabric from Figure 51 on page 336, but with AD0 and
AD255 shown. AD0 contains the two devices that are not in any of the user-defined Admin
Domains (AD1 and AD2). AD255 encompasses the entire physical fabric.