Troubleshooting I/O devices
You can determine the cause of device problems.
Device software check
Correct a device software problem by:
- Checking the Error Log
- Listing All Devices
- Checking the State of a Device
- Checking the Attributes of a Device
- Changing the Attributes of a Device
- Using a Device with Another Application
- Defining a New Device
Error log check
Check the error log to see whether any errors are recorded for either the device, its adapter, or the application using the device. Go to Error Logging Facility for information about performing this check. Return to this step after completing the procedures.
Did you correct the problem with the device?
If you were not able to correct the correct the problem using the previous method, go to the next step (Device listing) to list all of the devices.
Device listing
Use the lsdev -C command to list all defined or available devices. This command shows the characteristics of all the devices in your system.
If the device is in the list of devices, go to the next step (Device state check) to check the state of the device.
If the device is not in the list of devices, define a new device (see New device definition, below).
Device state check
Find the device
in the list generated from the lsdev -C command. Check whether the
device is in the Available state.
If the device is
in the Available state, go to the next step (Device attribute
check) to check the device attributes.
If the device is not in the Available state,
define a new device (see New device definition, below).
Device attribute check
Use the lsattr -E -l DeviceName command to list the attributes of your device.
The lsattr command shows attribute characteristics and possible values of attributes for devices in the system. Refer to the documentation for the specific device for the correct settings.
If the device attributes are set correctly, see Device use with another application, below.
If the device attributes are not set correctly, go to the next step, Device attribute change.
Device attribute change
Use the chdev -l Name -a Attribute=Value command to change device attributes.
The chdev command changes the characteristics of the device you specify with the -l Name flag.
If changing the attributes did not correct the problem with the device, go to the next step, Device use with another application.
Device use with another application
Try using the device with another application. If the device works correctly with another application, there might be a problem with the first application.
If the device worked correctly with another application, you might have a problem with the first application. Report the problem to your software service representative.
If the device did not work correctly with another application, go to the next step, New device definition.
New device definition
Use the mkdev command to add a device to the system.
The mkdev command can either define and make available a new device or make available a device that is already defined. You can uniquely identify the predefined device by using any combination of the -c, -s, and -t flags.
If defining the device did not correct the problem, You can either stop and report the problem to your service representative or use a diagnostics program to test your device.