Z13 Parallel Sysplex Coupling Connectivity - IBM z13s Technical Manual

b. 12x IFB3 protocol supports a maximum of four CHPIDs and connects to the other HCA3-O port. Otherwise, use
the 12x IFB protocol. The protocol is auto-configured when conditions are met for IFB3. For more information, see
4.6.4, "HCA3-O (12x IFB) fanout (FC 0171)" on page 150.
c. Uses all available fanout slots. Allows no I/O drawer or other IFB coupling option.
d. One IC connection (or 'link') requires the definition of two CHPIDs ('logical ports').
The maximum for IFB links is 32, for ICA SR is 16, and for IC is 32. The maximum number of
combined external coupling links (active ICA SR links and IFB LR) is 80 per z13s server. And
z13s servers support up to 256 coupling CHPIDs per CPC, which provides enhanced
connectivity and scalability for a growing number of coupling channel types that is twice the
128 coupling CHPIDs that are supported on zEC12. Unlike the HCA3-O 12x InfiniBand links,
the ICA SR cannot define more than four CHPIDS per port.
Coupling CHPIDs: On z13s servers, each CF image continues to support a maximum of
128 coupling CHPIDs.
z13s servers support various connectivity options, depending on the connected servers.
Figure 4-8 shows z13s coupling link support for z13, zEC12, zBC12, z196, and z114 servers.
Figure 4-8 z13 Parallel Sysplex coupling connectivity
When defining IFB coupling links (CHPID type CIB), HCD defaults to seven subchannels.
Thirty-two subchannels are supported only on HCA2-O LR (1xIFB) and HCA3-O LR (1xIFB)
on zEC12 and later when both sides of the connection use 32 subchannels. Otherwise,
change the default value from 7 to 32 subchannels on each CIB definition.
In a Parallel Sysplex configuration, z/OS and coupling facility images can run on the same or
separate servers.There must be at least one CF that is connected to all z/OS images,
although there can be other CFs that are connected only to selected z/OS images. Two
coupling facility images are required for system-managed CF structure duplexing. In this
case, each z/OS image must be connected to both duplexed CFs.
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IBM z13s Technical Guide