No, No, think before you create a naming convention

I remember doing a review of a large customer who had grown by mergers and acquisitions.  We were discussing naming conventions, and did they have them.

“Naming conventions”, he said “we love them.  We have hundreds of them around the place”. He said it was to hard and disruptive to try to get it down to a small number of naming conventions.

I saw someone’s MQ configuration and wished they had thought through their naming convention, or asked someone with more experience.  This is what I saw

  • The MQ libraries were called CSQ910.SCSQAUTH
    • This is OK as it tells you what level of MQ you are using
    • It would be good to have a dataset alias of CSQ pointing to CSQ910.  Without this you have to change the JCL for all job, compiles, runs etc which had CSQ910.  When you moved from CSQ810 to CSQ900 you have change the JCL. If you then decide to go back to CSQ810 for a week, you have to change the JCL again.  With the alias is is easy – change the alias and the JCL does not need to change.    Change the alias again – and the JCL does not need to change.
  • The MQ logs were called CSQ710.QM.LOGCOPY1.DS01, … DS02,…DS03
    • This shows the classic problem of having the queue manager release as part of the object names.  It would have been better to have names like CSQ.QM.LOGCOPY1.DS01 without the MQ version in it.
    • The name does include a queue manager name of sorts, but a queue manager name of QM is not very good.  If you need another queue manager you will have names like QM, QMA, QMB so an inconsistent name.
    • It is good to have the queue manager name as part of the data set name, so if the queue manager was QM01 then have CSQ.QM01.
  • The page sets were CSQ710.QM.PAGESET0, CSQ710.QM.PAGESET1,  CSQ710.QM.PAGESET2,  CSQ710.QM.PAGESET3,  CSQ810.QM.PAGESET4, CSQ910.QM.PAGESET5
    • This shows the naming standard problem as it evolved over time.  They added more page sets, and used the MQ release as the High Level Qualifier.  The page sets are CSQ710,… CSQ810…,  CSQ910… – following the naming standard.

You do not invent a naming convention in isolation, you need to put an architect’s hat on and see the bigger picture, where you have production and test queue managers, different versions of MQ, and see MQ is just a small part of the z/OS infrastructure.

  • People often have one queue manager per LPAR, and call MQ after the LPAR.
  • You are likely to have multiple machines – for example to provide availability, so plan for multiple queue managers.
  • You may want different HLQ to be able to identify production queue manager data sets and test queue manager data sets..
  • The security team will need to set up profiles for queue managers. Having MQPROD and MQTEST as a HLQ may make it easier to set up.
  • The storage team (what I used to call data managers)  set up SMS with rules for data set placement. For example production pagesets with a name like MQPROD.**.PSID* go on the newest, fastest, mirrored disks.  MQTEST.** go on older disks.
  • As part of the SMS definitions, the storage team define how often, and when, to backup data sets.   A production page set may be backed up using flash copy once an hour.   (This is within the Storage subsystem and takes seconds.   It takes a copy by taking a copy of the pointers to the records on disk).   Non production get backed up overnight.

 

Lessons learned

  • For the IBM provided libraries, include the VRM in the data set names.
  • Define an alias pointing to the current libraries so applications do not need to change JCL.   You could have a Unix Services alias for the files in the zFS.
  • Do not put the MQ release in the queue manager data sets names.
  • Use queue manager names that are relevant and scale.
  • Talk to your security and storage managers about the naming conventions; what you want protected, and how you want your queue manager data sets to be managed.