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Chapter 4. Connectivity 127
Example 4-8 HiperSockets HOME addresses
HOME
10.10.4.234 IUTIQDF4LNK
10.10.4.235 IUTIQDF5LNK
10.10.5.236 IUTIQDF6LNK
Define the characteristics of each LINK statement using BSDROUTINGPARMS
To define the link characteristics such as MTU (1) and Subnet Mask (2), we use the
BSDROUTINGPARMS statement. If not supplied, defaults will be supplied from static routing
definitions in the BEGINROUTES, OMPROUTE configuration (if OMPROUTE is running), or
if none supplied, the stack's interface layer based on hardware capabilities and
characteristics of devices and links. We defined our links with the highest MTU size, as
shown in Example 4-9.
Example 4-9 BSDRoutingparms statements
BSDROUTINGPARMS TRUE
; Link name MTU Cost metric Subnet Mask Dest address
STAVIPA1LNK 1492 1 0 255.255.255.252 0
OSA2080LNK 1492 0 255.255.255.0 2 0
OSA20A0LNK 1492 0 255.255.255.0 0
OSA20C0LNK 1492 0 255.255.255.0 0
OSA20E0LNK 1492 0 255.255.255.0 0
IUTIQDF4LNK 57344 0 255.255.255.0 0
IUTIQDF5LNK 57344 0 255.255.255.0 0
IUTIQDF6LNK 57344 0 255.255.255.0 0
; ENDBSDROUTINGPARMS
4.4.3 DYNAMICXCF implementation
To implement XCF connections in our test environment, we can use three different types of
devices:
DynamicXCF HiperSockets device (IUTIQDIO) for connections between z/OS LPARs
within the same server
DynamicXCF SAMEHOST device (IUTSAMEH) for stacks within the same LPAR
VTAM dynamically created ISTLSXCF to connect z/OS LPARs in other servers within the
same Sysplex.
Figure 4-14 on page 128 shows our DynamicXCF implementation, using HiperSockets
CHPID F7.
When using dynamic XCF for Sysplex configuration, make sure that XCFINIT=YES or
XCFINIT=DEFINE is coded in the VTAM start options, or if XCFINIT=NO was specified, issue
the VARY ACTIVATE command for the ISTLSXCF major node. This ensures that XCF
connections between TCP stacks on different VTAM nodes in the sysplex can be established.
The VTAM ISTLSXCF major node must be active for DYNAMICXCF work, except for the
following scenarios:
Multiple TCP/IP stacks on the same LPAR; a dynamic SAMEHOST definition is generated
whether ISTLSXCF is active or not.
HiperSockets is configured and enabled across multiple z/OS LPARs that are in the same
sysplex and the same server. If this is the case, a dynamic IUTIQDIO link is created
whether ISTLSXCF is active or not.