HP XP Racks - Manual (Page 720)

Allocating a Log Dataset
Specify log datasets as follows:
•
For TSO/E, after logging on, use the ALLOC command to specify YKLOG01 DD and YKLOG02
DD
statements. Alternatively, use a command procedure to specify YKLOG01 DD and YKLOG02
DD statements.
•
For a script, specify YKLOG01 DD and YKLOG02 DD statements for the JCL during script
execution.
The following is an example specification for a script or logon procedure:
//YKLOG01 DD DSN='USER01.YKLOG01',DISP=OLD,VOL=SER=WKVL01,UNIT=DASD
//YKLOG02 DD DSN='USER01.YKLOG02',DISP=OLD,VOL=SER=WKVL01,UNIT=DASD
The following is an example of TSO/E input that allocates the log dataset in advance:
ALLOC DS('USER01.YKLOG01') VOL(WKVL01) NEW SP(100) CYL
ALLOC DS('USER01.YKLOG02') VOL(WKVL01) NEW SP(100) CYL
Allocate a log dataset for each job. After the jobs terminates, the log dataset can be reused by
another job. In such a case, log output is appended to the end of the previous output.
In cases such as the following, reallocate a new log dataset instead of using the existing one:
•
If an I/O error occurs for the log dataset
•
If the OS crashes
Writing to a Log Dataset
If both YKLOG01 DD and YKLOG02 DD statements are specified, processing is performed as
follows:
1.
Logs are written to YKLOG01. If the log dataset is reused, log output is appended to the
previous output.
2. If YKLOG01 becomes full, logs are written to YKLOG02.
3. If YKLOG02 becomes full, logs are written to YKLOG01. In this case, the previously existing
data in YKLOG01 is overwritten.
4. Steps 2 and 3 are repeated.
If neither the YKLOG01 DD nor YKLOG02 DD statement are specified, the YKZ261E message is
output, and processing continues without any logs being obtained. If this happens, to obtain log
data, you need to log on to TSO/E again, and specify the DD statements for YKLOG01 and
YKLOG02
.
If either the YKLOG01 DD or YKLOG02 DD statement is specified, the YKZ261E message is output,
and log data is output only to the log dataset specified in the DD statement. In this case, the specified
log dataset is overwritten if it is full, starting from the beginning of the file.
If an I/O error occurs for YKLOG01 or YKLOG02, a message ranging from YKZ262E to YKZ264E
is output, and log data is output only to datasets for which I/O errors have not occurred. If this
happens, the log dataset is overwritten if it is full, starting from the beginning of the file. If I/O
errors occur for both datasets, processing continues without any log data being obtained.
Open or close log datasets as follows:
•
Log datasets (YKLOG01 and YKLOG02) are opened whenever a CLI command is executed.
However, if the log dataset has already been opened using the YKLOAD command, it cannot
be opened until the script terminates.
•
If the log dataset is opened using the YKLOAD command, the OS will close the log dataset
after the task terminates. If the log dataset is opened using a CLI command other than the
YKLOAD
command, the dataset will be closed after the CLI command terminates. Also, if a
log dataset (YKLOG01 or YKLOG02) becomes full, it will be closed (CLOSE TYPE=T ).
720 Troubleshooting