IBM z/OS Management Facility (z/OSMF)

IBM z/OSMF

IBM z/OSMF

The IBM z/OS Management Facility framework improves programmer productivity by using simplified, streamlined and automated tasks. This easier-to-use functionality reduces both programmer training time and the learning curve.

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  • 1.  IZUG038E The file system mounted on user directory is not available.

    Posted Tue October 03, 2023 07:10 AM

    We run zOSMF on a 6-way sysplex and until recently used automation to start zOSMF (IZUSVR1) on one of the plex members. For various reasons we have decided to remove zOSMF automation from all member systems and use AUTOSTART. Each plex member has:

    AUTOSTART(LOCAL)
    AUTOSTART_GROUP(IZUDFLT)

    specified in IZUPRMxx, and CEA is active on each system. 

    Now when we shutdown one of the systems and IPL, we obtain the error:

    IZUG038E The file system mounted on user directory is not available.
     M 4000000 GZT1     2023276 08:45:37.05          00000090  IZUG002E The address space IZUSVR1 failed to start. The following
     S                                                         error 138
     E                                           138 00000090  codes were returned: Return code        8, reason code        8

    This is despite the fact that there is no IZUSVR1 running on any of the other systems, and we are running a shared-zFS configuration.  If we wait until the IPL is complete, we can manually start IZUSVR1 on the system where it failed, with no issues. It is as if an enqueue on /global/zosmf is in place only during the period of the IPL.

    Has anybody else seen something similar ?

    Thanks and regards,

    Martin



    ------------------------------
    martin hall
    ------------------------------


  • 2.  RE: IZUG038E The file system mounted on user directory is not available.

    Posted Tue October 10, 2023 08:05 AM

    Martin,

       In a sysplex, if z/OSMF in each LPAR is configured to be AUTOSTART(LOCAL) and the same AUTOSTART_GROUP(IZUDFLT). In addition, all of z/OSMFs are using the same user directory mounted on a specific zFS filesystem. In this case,  the user directory is /global/zosmf. When the LPARs in the sysplex are IPLed in the meantime, only one z/OSMF is allowed to start. A enqueue with major name 'ZOSMF' and minor name AUTOSTART_GROUP plus zFS file system is used to control the contest. Once the z/OSMF obtains the enq during IPL, other z/OSMFs will failed to start with message IZUG038E appearing in the console. The enqueue obtained by the z/OSMF will be released until the z/OSMF is terminated. So I suppose you saw the message IZUG038E because there was another z/OSMF running on the sysplex which already hold the enqueue not released yet. But you mentioned, after IPL, you were able to manually start the z/OSMF failed to start.  Can you issue the below command from the z/OSMF? I want to check if the AUTOSTART_GROUP is the same as another z/OSMF which starts in IPL. Usually, there must be some configuration such as AUTOSTART_GROUP or server type being different which cause the z/OSMF can be started manually with ignoring the existence of another z/OSMF running.

    From both the z/OSMF manually started and the one IPLed, please help issue below commands and take the output for me to investigate.

    D GRS,RES=(ZOSMF,*)

    Thanks,



    ------------------------------
    JIAN GUO CHEN
    ------------------------------



  • 3.  RE: IZUG038E The file system mounted on user directory is not available.

    Posted Tue October 10, 2023 11:29 AM

    Hi Jian,

    Many thanks for your response.

    I'm familiar with the enqueue restrictions you describe - relating to the shared /global/zosmf directory and the AUTOSTART_GROUP ; we've seen those sort of enqueue situations ourselves in the past.  We  do specify the identical data directory and  AUTOSTART_GROUP for all sysplex members - and that is by design - since we want the server task to be able to run (uniquely) on ANY sysplex member .  However, as far as we can ascertain, at the time of the  IPL of this one sysplex member,  there were no server tasks running on any other of the sysplex members; certainly SDSF shows no other active tasks in the sysplex. I agree that the fact that we can successfully manually start the server later on the IPL'ed system implies some sort of enqueue issue is being detected by the  zOSMF server on the IPL'ing system,  and during IPL. 

    We'll look to issue the D GRS,RES=(ZOSMF,*) command at points during the IPL, and get back to you.

    Regards,

    Martin

     

     

     



    ------------------------------
    martin hall
    ------------------------------



  • 4.  RE: IZUG038E The file system mounted on user directory is not available.

    Posted Tue October 10, 2023 10:20 AM
    Hi Martin,

      On a sysplex, if the z/OSMF in each LPAR is configured with the same AUTOSTART(LOCAL) and AUTOSTART_GROUP(IZUDFLT), in addition, all of the z/OSMFs use the same user directory mounted on specific zFS filesystem. In this case, the user directory is /global/zosmf. Under these circumstances, when IPLing the LPARs in the meantime, only one z/OSMF is allowed to be started. The enqueue with major name set as ZOSMF and minor name set as AUTOSTART_GROUP plus zFS filesystem is used to control the concurrent starts of z/OSMFs. The z/OSMF which is started obtains the enqueue. Other z/OSMFs will fail to start accompanied with the message IZUG038E appearing in the console indicating enqueue obtaining fails. The enqueue will be released until the z/OSMF started is terminated. As you mentioned, you saw the message IZUG038E during IPL. I suppose there was another z/OSMF running on the sysplex at that time with the enqueue gained and not released yet. Furthermore, you mentioned you were able to start the z/OSMF failed to obtain the enqueue manually after IPL. Usually, the z/OSMF should use a different set of configurations on AUTOSTART_GROUP as well as server type specified on z/OSMF server PROC. In order to figure out the root cause, can you pls help issue the below command respectively on the z/OSMF started in IPL and another one manually started?

    Here is command to be issued:

    D GRS,RES=(ZOSMF,*)

    Thanks,

    Regards,
    JianGuo Chen





  • 5.  RE: IZUG038E The file system mounted on user directory is not available.

    Posted Fri October 13, 2023 05:48 AM

    Hi Jian,

    So  I set up an automatic command to issue D GRS,RES=(ZOSMF,*) on ALL sysplex members at 10-second intervals. I then ensured IZUSVR1 was not running on ANY sysplex members ,before closing down and IPL'ing one of the sysplex members with the following IZU parms :

    HOSTNAME('ZOSMFGZP.SPMF.BARCLAYS.CO.UK')
    HTTP_SSL_PORT(55444)
    SAF_PREFIX('IZUDFLT')
    PLUGINS(COMMSERVER_CFG,CAPACITY_PROV,ZERT_ANALYZER,
    ISPF,RESOURCE_MON,SOFTWARE_MGMT,SYSPLEX_MGMT,
    WORKLOAD_MGMT, INCIDENT_LOG)
    SESSION_EXPIRE(15)
    JAVA_HOME('/usr/lpp/java/J8.0_64')
    KEYRING_NAME('IZUKeyring.IZUDFLT')
    AUTOSTART(LOCAL)
    AUTOSTART_GROUP('IZUDFLT')
    USER_DIR(/global/zosmf/)
    CSRF_SWITCH(OFF)

    The enqueue command consistently showed:

    MR0000000 GZT1     2023286 08:39:26.68 INTERNAL 00000090  IEE421I RO *ALL,D GRS,RES=(ZOSMF 632
    LR                                          632 00000090  GZK4     RESPONSES ------------------------------
    DR                                          632 00000090  ISG343I 08.39.25 GRS STATUS 326
    DR                                          632 00000090  NO REQUESTORS FOR RESOURCE  ZOSMF    *
    LR                                          632 00000090  GZK5     RESPONSES ------------------------------
    DR                                          632 00000090  ISG343I 08.39.25 GRS STATUS 307
    DR                                          632 00000090  NO REQUESTORS FOR RESOURCE  ZOSMF    *
    LR                                          632 00000090  GZT1     RESPONSES ------------------------------
    DR                                          632 00000090  ISG343I 08.39.25 GRS STATUS 626
    DR                                          632 00000090  NO REQUESTORS FOR RESOURCE  ZOSMF    *
    LR                                          632 00000090  GZT2     RESPONSES ------------------------------
    DR                                          632 00000090  ISG343I 08.39.25 GRS STATUS 128
    DR                                          632 00000090  NO REQUESTORS FOR RESOURCE  ZOSMF    *
    LR                                          632 00000090  GZT3     RESPONSES ------------------------------
    DR                                          632 00000090  ISG343I 08.39.25 GRS STATUS 954
    DR                                          632 00000090  NO REQUESTORS FOR RESOURCE  ZOSMF    *
    LR                                          632 00000090  GZT4     RESPONSES ------------------------------
    DR                                          632 00000090  ISG343I 08.39.25 GRS STATUS 093
    DR                                          632 00000090  NO REQUESTORS FOR RESOURCE  ZOSMF    *

    LR                                          632 00000090  GZT5     RESPONSES ---------------------
    DR                                          632 00000090  ISG343I 08.39.25 GRS STATUS 931
    DR                                          632 00000090  NO REQUESTORS FOR RESOURCE  ZOSMF    *
    LR                                          632 00000090  GZT6     RESPONSES ---------------------
    DR                                          632 00000090  ISG343I 08.39.25 GRS STATUS 074
    ER                                          632 00000090  NO REQUESTORS FOR RESOURCE  ZOSMF    *

    ie no evidence of an existing enqueue, before the initialization error is issued on the IPL'ing system:

    N 4000000 GZT5     2023286 08:42:33.32          00000090  IZUG038E The file system mounted on user directory is not available.
    M 4000000 GZT5     2023286 08:42:33.32          00000090  IZUG002E The address space IZUSVR1 failed to start. The following
    S                                                         error 804
    E                                           804 00000090  codes were returned: Return code        8, reason code        8

    Regards,

    Martin

      



    ------------------------------
    martin hall
    ------------------------------



  • 6.  RE: IZUG038E The file system mounted on user directory is not available.

    Posted Mon October 16, 2023 02:54 AM

    Hi Martin,

       Thanks for the information. From the log, there was no resource related to 'z/OSMF' in any system in the sysplex, but the message IZUG038E  did appear in GZT5. The situation doesn't add up. There is one more thing left to check.  I want to check if there was a z/OSMF started in a system but ending up with failure somehow. In the case, the enqueue was hold by the system but released with the failure. You can find out similar message in the console if existing.

    M 0080000 SY1      23289 02:31:37.30          00000000  IRR812I PROFILE IZUSVR1.* (G) IN THE STARTED CLASS WAS USED 443
    E                                         443 00000000          TO START IZUSVR1 WITH JOBNAME IZUSVR1.                 

        If the above message is not seen in any system, would you please help open a case on the issue? I need the assistant from GRS team investigating ENQ service.

    Thanks,



    ------------------------------
    JIAN GUO CHEN
    ------------------------------



  • 7.  RE: IZUG038E The file system mounted on user directory is not available.

    Posted Thu October 19, 2023 08:11 AM

    Hi Jian

    Yes there is definitely something strange going on.

    I can see NO evidence of any messages of the kind:

    IRR812I PROFILE IZUSVR1.* 

    on any of the sysplex members during the period of the shutdown/IPL. A  couple of  further observations:

    If while no systems are running zOSMF,  I update parmlib member COMMND00 on ONE  system to specify an automatic start of zOSMF ie:


    COM='S IZUANG1'
    COM='S IZUSVR1,MSGCLASS=H'

    and then shutdown/re-IPL that system, IZUSVR1 starts normally and initializes. 

    If I update another system, this time - with no entry in COMMND00 - and to use a different mount point, say /globala/zosmf/, and a different autostart group say IZUDFLTA (and specify LOCAL) , and then shut down and IPL THAT system, I still get the error message at IPL, 

    and IZUSVR1 fails to start.

    One question - does IZUG038E DEFINITELY relate to the /global/zosmf/ (or equivalent) directory?

    If so then there is definitely something odd about the way an AUTOSTARTed IZUSVR1 is trying to access the zFS in our environment. I feel there would be some profit in doing some applicable tracing around the generation of  IZUG038E.

    I have raised a case with IBM

    Thanks and Regards,

    Martin 

     

     



    ------------------------------
    martin hall
    ------------------------------



  • 8.  RE: IZUG038E The file system mounted on user directory is not available.

    Posted Thu October 19, 2023 09:23 PM

    Hi Martin,

       Thanks for the experiment and opening a case. I think it's very helpful for us to investigate the issue. As you described, seems the issue occurs when shared zFS file system is used for z/OSMF. But for AUTOSTART, we use the enqueue with major name 'ZOSMF' instead of 'SYSDSN'. Minor name is AUTOSTART group followed by zFS filesystem. That is, the enqueue is only used to control the concurrent of z/OSMF start. It won't hold the lock on zFS filesystem self like dfsms service does. I will follow this up with team on the issue. I believe we will need your help during investigating like collecting trace. Thanks in advance.



    ------------------------------
    JIAN GUO CHEN
    ------------------------------