text: Figure 3-5 Overview of eight-path host zoning 
  
  For more information, see Chapter 8, “Hosts” on page 317. 
  
  **3.6.6 Zoning considerations for Metro Mirror and Global Mirror**
  
  The SAN configurations that use intercluster Metro Mirror and Global Mirror relationships 
  require the following other switch zoning considerations: 
  
  (cid:2) Review the latest requirements and recommendations at this website. 
  
  (cid:2) If two ISLs are connecting the sites, split the ports from each node between the ISLs. That 
  is, exactly one port from each node must be zoned across each ISL. 
  
  (cid:2) Local clustered system zoning continues to follow the standard requirement for all ports on 
  all nodes in a clustered system to be zoned to one another. 
  
  When designing zoning for a geographically dispersed solution, consider the effect of the 
  cross-site links on the performance of the local system. 
  
  **Important:**Be careful when you perform the zoning so that ports that are dedicated for 
  intra-cluster communication are*not*used for Host/Storage traffic in the 8-port and 12-port 
  configurations. 
  
  The use of mixed port speeds for intercluster communication can lead to port congestion, 
  which can negatively affect the performance and resiliency of the SAN. Therefore, it is not 
  supported. 