Use LOGR Couple Data Set at format level HBB7705

Description

IBM recommends that you use the highest format level LOGR couple data set (CDS) that can be used by the lowest system release level in your sysplex. This will allow for the latest system logger features to be available, given the sysplex configuration. Currently, the highest LOGR CDS format level is HBB7705 (introduced in z/OS V1R2). This format level is established by providing the ITEM NAME(SMDUPLEX) NUMBER(1) specification in the IXCL1DSU couple data set format utility program.

Table 1 provides more details about the migration action. Use this information to plan your changes to the system.

Table 1. Information about this migration action
Element or feature: BCP.
When change was introduced: z/OS V1R2.
Applies to migration from: z/OS V2R1 and z/OS V1R13.
Timing: Before installing z/OS V2R2.
Is the migration action required? No, but recommended to allow for the latest system logger features to be available, given the sysplex configuration. If your LOGR couple data sets are already at HBB7705 level, this migration action does not apply to you.
Target system hardware requirements: None.
Target system software requirements: None.
Other system (coexistence or fallback) requirements: None.
Restrictions: System Logger does not allow the introduction of an alternate LOGR CDS that is formatted at a lower-level than the primary.
System impacts: None.
Related IBM Health Checker for z/OS check: None.

Steps to take

Follow these steps:
  1. Determine your current LOGR couple data set level. Use the D XCF,C,TYPE=LOGR command. If your LOGR couple data sets are at level HBB7705, you do not need to perform this migration action.
  2. Use the IXCL1DSU (format couple data set utility) and include the ITEM NAME(SMDUPLEX) NUMBER(1) specification to obtain at least two LOGR CDSs at the HBB7705 format level, with:
    • LOGR CDS primarydsname on volume primaryvolume
    • LOGR CDS alternatedsname on volume alternatevolume
    Note: SMDUPLEX item NUMBER(1) is the default value when you run the IXCL1DSU utility on z/OS V2R2.
  3. After you create the HBB7705 format-level LOGR CDSs, you can dynamically bring them into your existing sysplex with these SETXCF commands:
    • SETXCF COUPLE,TYPE=LOGR,ACOUPLE=(primarydsname,primaryvolume)
    • SETXCF COUPLE,TYPE=LOGR,PSWITCH
    • SETXCF COUPLE,TYPE=LOGR,ACOUPLE=(alternatedsname,alternatevolume)
  4. Remember to also specify, in your COUPLExx member of SYS1.PARMLIB, these two LOGR CDSs as the primary and alternate for any future sysplex IPLs:
    DATA                               
  TYPE(LOGR)                         
  PCOUPLE(primarydsname,primaryvolume)
  ACOUPLE(alternatedsname,alternatevolume)
Note: If you did not bring the newly formatted HBB7705 LOGR CDSs into the sysplex (with the SETXCF commands in the Step 3) prior to the first z/OS system that IPLs into the sysplex using the COUPLExx member identifying the newly formatted LOGR CDSs, then there will be no persistent logger data from before the IPL. Therefore, no log stream data exists when this first system IPLs.

Reference information

For more information, see the following references:
Parent topic: BCP actions to perform before installing z/OS V2R2