Recovering a failed FCP device

6.10 LPAR mode z/VM guest

Failed FCP devices are automatically recovered by the zfcp device driver. You can read the in_recovery attribute to check whether recovery is under way.

Before you begin

The FCP device must be online.

Procedure

Perform these steps to find out the recovery status of an FCP device and, if needed, start or restart recovery:

  1. Issue a command of this form: 
    # cat /sys/bus/ccw/drivers/zfcp/<device_bus_id>/in_recovery

    The value is 1 if recovery is under way and 0 otherwise. If the value is 0 for a non-operational FCP device, recovery might have failed. Alternatively, the device driver might have failed to detect that the FCP device is malfunctioning.

  2. To find out whether recovery failed, read the failed attribute. Issue a command of this form: 
    # cat /sys/bus/ccw/drivers/zfcp/<device_bus_id>/failed
    The value is 1 if recovery failed and 0 otherwise.
  3. You can start or restart the recovery process for the FCP device by writing 0 to the failed attribute. Issue a command of this form: 
    # echo 0 > /sys/bus/ccw/drivers/zfcp/<device_bus_id>/failed

Example

In the following example, an FCP device with a device bus-ID 0.0.3d0c is malfunctioning. The first command reveals that recovery is not already under way. The second command manually starts recovery for the FCP device:

# cat /sys/bus/ccw/drivers/zfcp/0.0.3d0c/in_recovery
0
# echo 0 > /sys/bus/ccw/drivers/zfcp/0.0.3d0c/failed