Dell Brocade G620 Brocade 8.0.1 Fabric OS Administratiors Guide - Page 303

Administering Advanced Zoning ∙ Zone using the core switch in preference to using an edge switch. ∙ Zone using a Backbone rather than a switch. A Backbone has more resources to handle zoning changes and implementations. ∙ When you are adding a switch to an existing fabric, prior to joining the fabric you must set the defzone policy of the switch being added as follows: - If the joining switch has locally-attached devices that are online, the defzone policy of the switch being added should be set to "No Access". - If the joining switch has no online locally-attached devices the defzone policy of the switch being added can be set to "All Access". This is done to avoid a transitional state where the "All Access" policy might lead to excessive RSCN activity; with extreme cases having the potential for additional adverse effects. This is especially important for fabrics having a very high device count. ∙ Initial WWNs starting with '00' are for engineering use only and are auto-created. Starting with Fabric OS 7.3.0, zones having initial WWNs starting with '00' are treated as peer zones. This means that when you attempt one of the following, - A firmware upgrade from firmware earlier than Fabric OS 7.3.0 - A merge with a switch running firmware earlier than Fabric OS 7.3.0 - A configuration download using firmware earlier than Fabric OS 7.3.0 and the WWN of the first zone member starts with '00', Fabric OS will treat the zone as a peer zone. You must delete such invalid zones before continuing. Refer to Deleting invalid zones on page 325 for instructions on doing so. 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 , that 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. To restrict broadcast frames reaching broadcast-incapable devices, create a broadcast zone and populate it with the devices that are capable of handling broadcast packets. Devices that cannot handle broadcast frames must be kept out of the broadcast zone so that they do not receive any broadcast frames. You create a broadcast zone the same way you create any other zone except that a broadcast zone must have the name "broadcast" (case-sensitive). To enable the broadcast zoning, use cfgenable command to add the broadcast zones to the active zone configuration. You set up and manage broadcast zones using the standard zoning commands, described in Zone creation and maintenance on page 307. Brocade Fabric OS Administration Guide, 8.0.1 53-1004111-02 303