Finding out what the BSDS contains
You can use the print log map utility (CSQJU004) to examine the contents of the BSDS.
The print log map utility (CSQJU004) is a batch utility that lists the information stored in the BSDS. For instructions on running it, see The print log map utility.
The BSDS contains:
- Time stamps in the BSDS
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The output of the print log map utility shows the time stamps, which are used to record the date and time of various system events, that are stored in the BSDS.
The following time stamps are included in the header section of the report:- SYSTEM TIMESTAMP
- Reflects the date and time the BSDS was last updated. The BSDS time stamp can be updated when:
- The queue manager starts.
- The write threshold is reached during log write activities. Depending on the number of output buffers you have specified and the system activity rate, the BSDS might be updated several times a second, or might not be updated for several seconds, minutes, or even hours. For details of the write threshold, see the WRTHRSH parameter of the CSQ6LOGP macro in Using CSQ6LOGP.
- IBM® MQ drops into a single BSDS mode from its normal dual BSDS mode due to an error. This can occur when a request to get, insert, point to, update, or delete a BSDS record is unsuccessful. When this error occurs, IBM MQ updates the time stamp in the remaining BSDS to force a time stamp mismatch with the disabled BSDS.
- UTILITY TIMESTAMP
- The date and time the contents of the BSDS were altered by the change log inventory utility (CSQJU003).
The following time stamps are included in the active and archive log data sets portion of the report:- Active log date
- The date the active log entry was created in the BSDS, that is, when the CSQJU003 NEWLOG was done.
- Active log time
- The time the active log entry was created in the BSDS, that is, when the CSQJU003 NEWLOG was done.
- Archive log date
- The date the archive log entry was created in the BSDS, that is, when the CSQJU003 NEWLOG was done or the archive itself was done.
- Archive log time
- The time the archive log entry was created in the BSDS, that is, when the CSQJU003 NEWLOG was done or the archive itself was done.
- Active log data set status
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The BSDS records the status of an active log data set as one of the following:
- NEW
- The data set has been defined but never used by IBM MQ, or the log was truncated to a point before the data set was first used. In either case, the data set starting and ending RBA values are reset to zero.
- REUSABLE
- Either the data set has been defined but never used by IBM MQ, or the data set has been offloaded. In the print log map output, the start RBA value for the last REUSABLE data set is equal to the start RBA value of the last archive log data set.
- NOT REUSABLE
- The data set contains records that have not been offloaded.
- STOPPED
- The offload processor encountered an error while reading a record, and that record could not be obtained from the other copy of the active log.
- TRUNCATED
- Either:
- An I/O error occurred, and IBM MQ has stopped writing to this data set. The active log data set is offloaded, beginning with the starting RBA and continuing up to the last valid record segment in the truncated active log data set. The RBA of the last valid record segment is lower than the ending RBA of the active log data set. Logging is switched to the next available active log data set, and continues uninterrupted.
- An ARCHIVE LOG function has been called, which has truncated the active log.