content_image/993440.jpg
## Migration considerations 

Upgrading from previous generations of IBM Z servers in a Parallel Sysplex to IBM z14™ servers in that same Parallel Sysplex requires proper planning for coupling connectivity. 

Planning is important because of the change in the supported type of coupling link adapters and the number of available fanout slots of the z14 CPC drawer, as compared to the number of available fanout slots of the processor books of the previous generation Z servers, such as zEC12. 

IBM z14™ does not support ISC-3 links, HCA2-O, or HCA2-O (LR). 

HCA3-O link compatibility:  HCA3-O (LR) links can  connect to HCA2-O (LR) on zEC12 and zBC12. 

z196 and z114 are not  supported in same Parallel Sysplex or STP CTN with IBM z14™. 

The ICA SR fanout provides short-distance connectivity to another IBM z14™/z13s/z13 server. For more information, see Table 4-11 on page 185. 

The CE LR adapter provides long-distance connectivity to another IBM z14™/z13s/z13 server. For more information, see “Coupling links” on page 185 

The z14 server fanout slots in the CPC drawer provide coupling links connectivity through the ICA SR and IFB fanout cards. In addition to coupling links for Parallel Sysplex, the fanout cards that the fanout slots provide connectivity for the PCIe I/O drawer (PCIe fanout). 

Up to 10 PCIe and 4 IFB fanout cards can be installed in each CPC drawer, as shown in Figure 4-7. 

<img src='content_image/993440.jpg'>

Previous generations IBM Z platforms, in particular z196 and zEC12, use processor books, which provide connectivity for up to eight InfiniBand fanouts per book. 

