POWER7 information

chkdev command

Purpose

Checks devices for virtual device provisioning capability in the Virtual I/O Server.

Syntax

chkdev [-dev Name] [-verbose] [-field FieldName …] [-fmt delimiter]

Description

The chkdev command determines whether a device can be used in physical to virtual transitions in the Virtual I/O Server. Devices include all physical volumes and multipath representations of logical units. If the -dev option is used, information is shown for the device specified. If the -verbose option is used, detailed information is shown. With the -field option, the user can specify which fields to display. With the -fmt option, the user can format the output to be separated by a given delimiter.

Capability in a virtual environment refers to the capability for a device to move between a physical environment to a virtual environment. The command displays these fields: Phys2Virt_Capable, Virt2NPIV_Capable, and Virt2Phys_Capable.

For a device to be capable of moving from a physical to a virtual environment, it must pass the address compatibility check. If the physical volume can be moved from a physical to a virtual environment, the Phys2Virt_Capable field has a value of YES. If the device is not capable of this move, the field has a value of NO. If the device is already in use by Virtual Small Computer System Interface (VSCSI), the field has a value of NA.

If a device is capable of moving from a VSCSI LUN environment to an N_Port ID Virtualization (NPIV) environment, it must pass the address-compatibility check. If this device can be moved, the Virt2NPIV_Capable field has a value of YES. If the device is not capable of this move, the field has a value of NO. If the device is not in use by the virtual target device (VTD), this field has a value of NA. This command is not sufficient to guarantee that the client can read the data after the VSCSI logical unit number (LUN) is removed. The storage area network (SAN) configuration must also be checked by the SAN administrator to ensure that it is mapped to a client NPIV.

Determination of whether a device is capable of moving from a virtual environment to a physical environment is applicable for devices that are mapped as VTDs. For devices to be capable of moving from a virtual environment to a physical environment, it must pass the address capability test. If the physical volume is capable of being transferred from a virtual environment to a physical environment, the Virt2Phys_Capable field has a value of YES. If the device is not capable of this move, the field has a value of NO. If the device is not in use by VTD, the field has a value of NA.

Flags

Flag name	Description
-dev Name	Specifies the device logical name for the device for which compatibility is checked.
-verbose	Displays additional details, including values for IEEE, unique_id, and PVID.
-field FieldName …	Specifies a list of fields to be displayed.
-fmt delimiter	Divides the output by using a user-specified delimiter character.

Exit Status

Return code	Description
0	The command completed successfully
>0	An error occurred.

Examples

To check device capability and to display unique identifier information for a particular device, type the following command:

chkdev -dev hdisk5 -verbose

The system displays a message similar to the following:

Name:                  hdisk5
IDENTIFIER:						210ChpO-c4JqYs9g04N37006NETAPPfcp
PHYS2VIRT_CAPABLE: 		NA
VIRT2NPIV_CAPABLE:			YES
VIRT2PHYS_CAPABLE:			YES
PVID:					
UDID:									210ChpO-c4JqYs9g04N37006NETAPPfcp
IEEE:					
VTD:               		vtscsi0

To check device capability and to display unique identifier information for a particular device, type the following command:

chkdev -dev hdisk6 –verbose

The system displays a message similar to the following:

Name:						       hdisk6
IDENTIFIER:						210ChpO-c4JqYs9g04N37006NETAPPfcp
PHYS2VIRT_CAPABLE: 		YES
VIRT2NPIV_CAPABLE:			NA
VIRT2PHYS_CAPABLE:			NA
PVID:					
UDID:					
IEEE:									210ChpO-c4JqYs9g04N37006NETAPPfcp
VTD:

To check device capability and to display unique identifier information for a particular device, type the following command:
```
chkdev -dev hdisk8 -verbose
```
The system displays a message similar to the following:
```
Name:					       	hdisk8
IDENTIFIER:				
PHYS2VIRT_CAPABLE: 		NO
VIRT2NPIV_CAPABLE:			NA
VIRT2PHYS_CAPABLE:			NA
PVID:				
UDID:					
IEEE:
VTD:
```

To check device capability for a particular device, type the following command:

chkdev -dev hdisk5

The system displays a message similar to the following:

Name:					       hdisk5
IDENTIFIER:					210ChpO-c4JqYs9g04N37006NETAPPfcp
PHYS2VIRT_CAPABLE: 	NA
VIRT2NPIV_CAPABLE:		YES
VIRT2PHYS_CAPABLE:		YES

To list the PHYS2VIRT_CAPABLE field for a particular device, type the following command:
```
chkdev -dev hdisk5 –field name phys2virt_capable
```
The system displays a message similar to the following:
```
Name:						       hdisk5
PHYS2VIRT_CAPABLE: 		NA
```

To check all devices for device-capability information, type the following command:

chkdev

The system displays a message similar to the following:

Name:						       hdisk5
IDENTIFIER:						210ChpO-c4JqYs9g04N37006NETAPPfcp
PHYS2VIRT_CAPABLE: 		NA
VIRT2NPIV_CAPABLE:			YES
VIRT2PHYS_CAPABLE:			YES

Name:						       hdisk6
IDENTIFIER:				
	PHYS2VIRT_CAPABLE: 		YES
VIRT2NPIV_CAPABLE:			NA
VIRT2PHYS_CAPABLE:			NA

Name:						       hdisk7
IDENTIFIER:						0000c2aaec372704
PHYS2VIRT_CAPABLE: 		NA
VIRT2NPIV_CAPABLE:			NO
VIRT2PHYS_CAPABLE:			NO

Name:						       hdisk8
IDENTIFIER:	
PHYS2VIRT_CAPABLE: 		NO
VIRT2NPIV_CAPABLE:			NA
VIRT2PHYS_CAPABLE:			NA

Related Information

The lsdev command and the rmdev command.

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Last updated: Wed, June 03, 2015