IMS ETO Support configuration overview

To ensure successful configuration of IMS ETO Support for your environment, make sure that the distribution load library is APF authorized and is added to the IMS control region JCL and message region JCL where IZTRAN is executed.

Note that APF authorization is required only for the IMS control region and the APPC refresh job (built by SIZTSAMP(IZTTPADD)). The IMS message regions do not require that their STEPLIB be APF authorized.

Also note that in order to use the IMS ETO Support transaction from a 3270 terminal, the OUTBUF size must be at least 3840 bytes:

• For dynamic terminals, this parameter is specified in the logon descriptor (PROCLIB member DFSDSCxx).
• For static terminals, the TERMINAL macro (or associated TYPE macro) must specify an OUTBUF size of at least 3840.

Before you configure IMS ETO Support, you may want to calculate E/CSA usage. Two formulas for doing this are shown; the number of LTERMs you are using determines which formula is to be used:

• If 0 or 1 LTERM is used for 3270/SLU2 and user ID entries, use the first formula.
• If 2 to 8 LTERMs are used for 3270/SLU2 and user ID entries, use the second formula.

  This formula calculates the maximum E/CSA that can be required, and it assumes that each and every 3270 and user ID entry has 8 LTERMs defined.

The following example shows the two formulas for calculating E/CSA usage:

Formula for 0 or 1 LTERMs:
E/CSA = ((x * 144) + (y * 100) + (z * 240) + (a * 128) + 4096)

Formula for 2 to 8 LTERMs:
E/CSA = ((x * 144) + (y * 100) + (z * 240) + (x * 128) + (y * 128) + (a * 128) + 4096)