Practical Considerations

Ignite-UX uses hardware paths to help you identify I/O devices such as disks, CD/DVD drives and tape drives during installation and recovery. The format of the hardware path used to identify I/O devices will depend on the version of HP-UX you are using and other factors. Also, depending on your configuration, multiple paths might be displayed for a single device.

For HP-UX 11i v3, Ignite-UX will allow HP-UX system software to select the best path when a particular path is needed. For example, boot paths will be selected by system software when the boot device is selected.

Note that horizontal scrolling might be required to read the entire hardware path and associated data in Ignite-UX GUI screens.

System Installation Configuration

When using Ignite to install HP-UX on a client, a root disk must be identified. Ignite-UX selects a default disk, but it may be changed using the Root Disk... button on the Basic tab on the client installation configuration interface shown below.

Figure 7-4 Ignite-UX Client Installation Configuration Tabs

The hardware path displayed in the Root Disk text box is the lunpath hardware path for HP-UX 11i v3 and later, or the legacy hardware path for HP-UX 11i v2 and earlier.

By selecting Root Disk..., the Disk Selection – Root Disk dialog box is displayed (Figure 7-5).

Figure 7-5 Disk Selection – Root Disk Dialog Box

The Disk Selection – Root Disk dialog box displays every path for each disk, therefore disks with multiple paths are listed multiple times. Set View By: to Disks/Paths (the default is I/O Protocol) to see what paths go to each disk. For more information on using the Disk Selection – Root Disk dialog box, see “Root disk... Button”.




	NOTE: Inventory blocking may be used to reduce the time required to discover devices during Ignite-UX start-up. Devices blocked from inventory will not be listed in the Disk Selection dialog boxes. For more information on using Ignite-UX variables such as `inventory_block_path` and `inventory_block_protocols`, see instl_adm(4), “Controlling the I/O Configuration Process”, and “Additional... Button”. For more information on the agile naming model, see Figure 7-3.

If you have a SAS device, physical locations will be displayed in the Disk Selection – Root Disk dialog box as shown in Figure 7-6.

Figure 7-6 Disk Selection – Root Disk Dialog Box With Physical Locations

To get a concise listing of all the paths for a single device, select the path of interest and then click the More Info button, or use the Disks/Paths View. If a LUN has multiple paths, you may select any of them to get to the same More Info screen. For example, you may select either of the lunpath hardware paths below since they both reference the same LUN.

0/0/6/0/0.0x50060b000019c8a6.0x4001000000000000

0/0/10/0/0.0x50060b000019c8a6.0x4001000000000000

Use the More Info screen to help make the transition from legacy hardware paths to the lunpath hardware paths. The More Info screen supplies details about a LUN to help you verify that the selected LUN is the one intended. Note that the legacy hardware path is also shown to the very right in the Path/Location window of the Disk Selection dialog box – use horizontal scrolling to see it.

Figure 7-7 More Info Dialog Box

For HP-UX 11i v3 and later, the More Info screen displays all the lunpath hardware paths for a device. (Note that the paths can be long - horizontal scrolling may be needed to see the entire path.) The Legacy HW Path displayed depends on the lunpath hardware path currently selected in the selection list window. One legacy hardware path is listed. For a concise list of all the legacy hardware paths leading to the device, select the All Paths... button (Figure 7-8).

The Legacy HW Path window and the All Paths... button are not available on systems running HP-UX 11i v2 and earlier.

Figure 7-8 All Paths Dialog Box

Accessed from the File System tab of the client installation configuration interface, the Disk Selection – Add/Remove Disks dialog box displays the lunpath hardware path, the legacy hardware path, or the physical location. See Figure 7-6 for the display format of physical location hardware paths.

Figure 7-9 Disk Selection – Add/Remove Disks Dialog Box

The More Info screen is made available on the Disk Selection – Add/Remove Disks dialog box too, to validate selections and help make the change to the agile naming model.

Identifying Devices for Other Tasks

There are a number of other Ignite tasks that require the identification of I/O devices:

When building installation media, you must use the ioscan command to find the tape, CD, or DVD drive. Note that some of the CD/DVD writing SW included with Ignite-UX but not developed by HP only works with legacy device special files.
When performing a system recovery on Itanium-based systems, you must find the tape device’s hardware path to create an EFI boot option. (This should be done at the time the tape is created.)
During two-step media recovery, you must select the hardware path of the tape drive to recover from.
When in expert recovery mode, you must have the hardware path of the disk you are attempting to recover.
When identifying disks in configuration files to define them or combine them in a single volume group, you must supply the hardware paths of the disks.

Important Characteristics of the Agile View

The following points will help you move from the legacy view to the agile view:

When using the new persistent DSFs, be sure to use the new directory structure:
Table 7-1 Mass Storage DSF Directories
Persistent DSF Directory Legacy DSF Directory
/dev/disk /dev/dsk
/dev/rdisk /dev/rdsk
/dev/rtape /dev/rmt
Both legacy and persistent DSFs can be created during installation and recovery of HP-UX 11i v3 depending on your volume manager. When Ignite-UX creates file system content for HP-UX 11i v3, persistent DSFs are used for LVM volumes and VxVM 5.0 layout, and legacy DSFs are used for VxVM 3.5 and 4.1.
NOTE: The VxVM components in the Ignite-UX install environment and the installation depot must be version 5.0 in order to use persistent DSFs.
Keep in mind that persistent DSFs endure with recovery if Ignite recovers to the same hardware or can map to replacement hardware, but are not guaranteed to remain the same between installations. See Figure 7-10 for an overview regarding consistency of I/O addressing.
If hardware is replaced and recovery is not needed, you might want to run io_redirect_dsf to correct the system configuration. For more information, see io_redirect_dsf(1M).

Figure 7-10 Consistency of I/O Addressing

Use the following key for the “Consistency of I/O Addressing” figure above.

C = Consistent — Device addressing id value is saved in HP-UX config content and the correlation between these values and devices does not change as a result of the event.

N = New Value — Device addressing id value is newly created as a result of the event. The device addressing id value for a device might or might not change as a result of the event.

R = Recovered — Ignite-UX will restore the association between device addressing id values and devices when possible. The process used to match previous and current devices is handled by Ignite-UX recovery matching methods. Matching might not be possible if the system configs differ.

* — Might be a consistent value for some I/O protocols such as parallel SCSI, and might be a new value for some I/O protocols such as fibre channel.

Practical Considerations

Technical documentation

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System Installation Configuration

Identifying Devices for Other Tasks

Important Characteristics of the Agile View