Failed SCSI devices are automatically recovered by the
zfcp device driver. You can read the zfcp_in_recovery attribute
to check whether recovery is under way.
Before you begin
The FCP device must be online.
Procedure
Perform the following steps to check the recovery status
of a failed SCSI device:
- Check the value of the zfcp_in_recovery attribute.
Issue the lszfcp command:
# lszfcp -l <LUN> -a
where <LUN> is
the LUN of the associated SCSI device.
Alternatively, you can
issue a command of this form:
# cat /sys/class/scsi_device/<device_name>/device/zfcp_in_recovery
The
value is 1 if recovery is under way and 0 otherwise.
If the value is 0 for a non-operational SCSI device,
recovery might have failed. Alternatively, the device driver might
have failed to detect that the SCSI device is malfunctioning.
- To find out whether recovery failed, read the zfcp_failed attribute. Either use the lszfcp command
again, or issue a command of this form:
# cat /sys/class/scsi_device/<device_name>/device/zfcp_failed
The value
is 1 if recovery failed, and 0 otherwise.
- You can start or restart the recovery process for the SCSI
device by writing
0 to the zfcp_failed attribute.
Issue a command of this form: # echo 0 > /sys/class/scsi_device/<device_name>/device/zfcp_failed
Example
In the following example,
SCSI device 0:0:0:0 is malfunctioning. The first command reveals that
recovery is not already under way. The second command manually starts
recovery for the SCSI device:
# cat /sys/class/scsi_device/0:0:0:0/device/zfcp_in_recovery
0
# echo 0 > /sys/class/scsi_device/0:0:0:0/device/zfcp_failed
What to do next
If you manually configured an FCP LUN,
but did not get a corresponding SCSI device, you can also use the
corresponding FCP LUN sysfs attributes, in_recovery and failed, to check on recovery.