Smart zoning implements hard zoning of large zones with fewer hardware resources than was previously required. The traditional zoning method allows each device in a zone to communicate with every other device in the zone, and the administrator is required to manage the individual zones. Smart zoning eliminates the need to create a single initiator to single target zones. By analyzing device-type information in the FCNS, the Cisco MDS NX-OS software can implement useful combinations at the hardware level, and the combinations that are not used are ignored. For example, initiator-target pairs are configured, but not initiator-initiator. The device is treated as unknown if during zone convert, the device is not logged in to the fabric, or when the zone is created, the initiator, target, or initiator and target are not specified.
The device-type information of each device in a smart zone is automatically populated from the Fibre Channel Name Server (FCNS) database as host, target, or both. This information allows more efficient utilization of switch hardware by identifying initiator-target pairs and configuring those only in hardware. In the event of a special situation, such as a disk controller that needs to communicate with another disk controller, the administrator can override smart zoning defaults to allow complete control.
After the zone set is converted to smart zoning, you need to activate the zone set. Smart zoning only supports PWWN, FCID, FCalias, and Device-alias zoning member configurations.
Note
Smart zoning can be enabled at the VSAN level but can also be disabled at the zone level.
Enhanced Zoning
There are two modes of zoning: basic (which is the default) and enhanced. You can enable enhanced zoning in a VSAN by using the zone mode enhanced vsan vsan-id command.
In enhanced zoning, modifications to the zone database are made within a session. A session is created at the time of the first successful configuration command. On creation of a session, a copy of the zone database is created. Any changes made within the session are performed on this copy of the zoning database. These changes in the copy zoning database are not applied to the effective zoning database until you commit the changes. When you apply the changes, the session is closed.
If the fabric is locked by another user, and for some reason the lock is not cleared, you can force the operation and close the session. You must have permission (role) to clear the lock in this switch and perform the operation on the switch from where the session was originally created. To release the session lock on the zoning database on the switches in a VSAN, use the no zone commit vsan command from the switch where the database was initially locked.
When two Fibre Channel (FC) switches that have already been configured with active zone sets and are not yet connected are brought together with an Extended ISL (EISL) link, the zone sets merge. In enhanced zoning, the merge method depends on the fabric-wide merge control setting:
Restrict: If the two databases are not identical, the ISLs between the switches are isolated.
Allow: The two databases are merged using the merge rules specified in Table 8-16.