Communications Server for z/OS V1R7 TCP/IP Implementation, Volume 1: Base Functions, Connectivity, and Routing

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.