Enabling and disabling logging

6.18 LPAR mode z/VM guest KVM guest

Use the dasd= kernel or module parameter or use the erplog sysfs attribute to enable or disable error recovery processing (ERP) logging.

Procedure

You can enable and disable error recovery processing (ERP) logging on a running system. There are two methods:

Use the dasd= parameter when you load the base module of the DASD device driver.
Example:
To define a device range (0.0.7000-0.0.7005) and enable logging, change the parameter line to contain:
```
dasd=0.0.7000-0.0.7005(erplog)
```
Use the sysfs attribute erplog to turn ERP-related logging on or off.
Logging can be enabled for a specific device by writing 1 to the erplog attribute.
Example:
```
# echo 1 > /sys/bus/ccw/devices/<device_bus_id>/erplog
```
To disable logging, write 0 to the erplog attribute.
Example:
```
# echo 0 > /sys/bus/ccw/devices/<device_bus_id>/erplog
```