Automatic dumpconf example

Edit online

In this example, a dump to DASD device 1004 is initiated using the dumpconf service. Furthermore, list-directed dumping is limited to one concurrent dump per CEC, that is, if another LPAR is being dumped at the same time, the dump process fails. Although only a single concurrent list-directed dump can be processed at a time and additional attempts may initially fail due to this limitation, the operation can be retried successfully once the dump resource becomes available again.

Procedure

Set up the dumpconf service.
To set up dumpconf for list-directed dump, you must know the device number of the chosen DASD dump device. The device number is shown in the output of the zipl command that installed the dump tool, for example 1004.
```
# cat /etc/sysconfig/dumpconf
ON_PANIC=dump
DUMP_TYPE=eckd
DEVICE=0.0.1004
BOOTPROG=0
BR_CHR=auto
```
Enable and start the dumpconf service at the same time:
```
# systemctl enable --now dumpconf
```
Optionally, trigger a crash to ensure that the dump works as intended.
For example:
```
# sync
# echo c > /proc/sysrq-trigger
```

z/VM guest example

In this example, a list-directed dump to ECKD DASD device 1004 is initiated from z/VM.

List-directed dumping is limited to one concurrent dump per z/VM that is, if another z/VM guest is being dumped at the same time, the dump process will fail. Furthermore, although only a single concurrent list-directed dump can be processed at a time and additional attempts may initially fail due to this limitation, the operation can be retried successfully once the dump resource becomes available again.

Example:

If 1004 is the dump device:

#cp cpu all stop

#cp set dumpdev eckd dev 1004 bootrec label
#cp i dumpdev

On z/VM you see messages about the list-lirected IPL initiated and dump process start:

00: LDIPL: Dump detected.                                                                                                 
...                                                                                             
[    0.236252] zdump: The dump process started for a 64-bit operating system

Wait until the dump process completes. You can IPL Linux again.