Identifying exportable disks

To export a physical volume as a virtual device, the physical volume must have an IEEE volume attribute, a unique identifier (UDID), or a physical identifier (PVID).

To identify exportable disks, complete the following steps:

Determine whether a device has an IEEE volume attribute identifier by running the following command from the Virtual I/O Server command line:
```
lsdev -dev hdiskX -attr 
```
Disks with an IEEE volume attribute identifier have a value in the ieee_volname field. Output similar to the following is displayed:
```
...
cache_method   fast_write                      Write Caching method
   False
ieee_volname   600A0B800012DD0D00000AB441ED6AC IEEE Unique volume name
   False
lun_id         0x001a000000000000              Logical Unit Number
   False
...
```
If the ieee_volname field does not appear, then the device does not have an IEEE volume attribute identifier.
If the device does not have an IEEE volume attribute identifier, then determine whether the device has a UDID by completing the following steps:
1. Type oem_setup_env.
2. Type odmget -qattribute=unique_id CuAt. The disks that have a UDID are listed. Output similar to the following is displayed:
```
CuAt:
	name = "hdisk1"
	attribute = "unique_id"
	value = "2708ECVBZ1SC10IC35L146UCDY10-003IBMscsi"
	type = "R"
	generic = ""
	rep = "nl"
	nls_index = 79

CuAt:
	name = "hdisk2"
	attribute = "unique_id"
	value = "210800038FB50AST373453LC03IBMscsi"
	type = "R"
	generic = ""
	rep = "nl"
	nls_index = 79
```
  Devices in the list that are accessible from other Virtual I/O Server partitions can be used in virtual SCSI MPIO configurations.
3. Type exit.

If the device does not have either an IEEE volume attribute identifier or a UDID, then determine whether the device has a PVID by running the following command:

lspv

The disks and their respective PVIDs are listed. Output similar to the following is displayed:

NAME        PVID                    VG       STATUS
hdisk0      00c5e10c1608fd80        rootvg   active
hdisk1      00c5e10cf7eb2195        rootvg   active
hdisk2      00c5e10c44df5673        None			
hdisk3      00c5e10cf3ba6a9a        None			
hdisk4      none                    None

If the device does not have either an IEEE volume attribute identifier, a UDID, or a PVID, then complete one of the following tasks to assign an identifier:
1. Upgrade your vendor software and then repeat this entire procedure, Identifying exportable disks, from the beginning. The latest versions of some vendor software include support for identifying devices using a UDID. Before upgrading, ensure that you preserve any virtual SCSI devices that you created when using the versions of the software that did not support identifying devices using a UDID. For information and upgrade instructions, see the documentation provided by your vendor software.
2. If the upgraded vendor software does not produce a UDID or IEEE volume attribute identifier, then put a PVID on the physical volume by running the following command:
```
chdev -dev hdiskX -attr pv=yes
```