Troubleshooting z/OS Services

The following topics contain information that can help you troubleshoot problems when you encounter unexpected behavior with z/OS services while installing and using Zowe™.

ISSUE: Unable to generate unique CeaTso APPTAG

Symptom: When you request a Zowe data set or z/OS Files API, you receive a response code 500 - 'Internal Server Error', with a message "Unable to generate unique CeaTso APPTAG".

Solution: Check the z/OSMF settings of REST API of file. You must define RESTAPI_FILE in IZUPRMxx by the following statement: RESTAPI_FILE ACCT(IZUACCT) REGION(32768) PROC(IZUFPROC) The default IZUFPROC can be found in SYS1.PPROCLIB. And the proper authorization is needed to get IZUFPROC to work successfully.

ISSUE: z/OSMF JVM cache corruption

Symptom:

When you work with Zowe, there are situations when z/OSMF abends. The following is a snippet from the Java core dump.

CEE3DMP V2 R4.0: Condition processing resulted in the unhandled condition.
...
Condition Information for Active Routines
Condition Information for (DSA address 0000005F026FDE40)
CIB Address: 0000005F026FA1E8
Current Condition:
CEE0198S The termination of a thread was signaled due to an
unhandled condition.
Original Condition:
CEE3250C The system or user abend SDC2 R=4A001620 was issued.
Location:
Program Unit: Entry: ntv_createJoinWorkUnit
Statement: Offset: +000ABD14
Machine State:
ILC..... 0002 Interruption Code..... 000D
PSW..... 0785240180000000 000000003825D954

Solution: The error occurs when the Java runtime being used by the z/OSMF Liberty server and the Java runtimes being used by Zowe share a user ID of IZUSVR1, which results in a collision. To resolve this issue, review the following steps:

1. Isolate the started task user IDs
2. Update z/OSMF to not use JVM class caching

Isolate the started task user IDs

The z/OSMF started task IZUSVR1 runs under the user ID of IZUUSER. Before version 1.9 of Zowe, its started task ZWESVSTC also ran under the same user ID. With Zowe 1.9, the default configuration changed to use a new user ID of ZWESVUSR and group of ZWEADMIN. If your started task ZWESVSTC is configured to run under the user ID IZUUSER, change it to run under user ID ZWESVUSR.

Update z/OSMF to not use JVM class caching

If you need to run ZWESVSTC under the same user ID as z/OSMF for your environment, you can update the z/OSMF configuration to switch off shared class caching which stops the crash from occurring. Disabling shared class caching reduces the performance of z/OSMF so the preferred fix is to change the user ID of ZWESVSTC away from IZUUSER to ZWESVUSR as described above. Navigate to the file /var/zosmf/configuration/local_override.cfg. This contains the startup arguments for the Java runtime used by z/OSMF. Add the following line:

JVM_OPTIONS=-Xshareclasses:none

You will need to recycle the z/OSMF server running, which by default will be running under the started task IZUSVR1.