Dynamic Root Disk Frequently Asked Questions (766143-001, March 2014)
1-14. Q:
Does the cloned root disk (VG) contain same VGID as the original root VG?
A:
The volume group will be vg00 when the clone is booted. It will have a different minor
number than the original vg00.
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1-15. Q:
How is lvmtab adjusted to reflect the new device name for the disk in vg00?
A:
The copy of lvmtab on the cloned image is modified by the clone operation to contain
information that will reflect the desired volume groups when the clone is booted.
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1-16. Q:
Do the DRD administration tools keep track of the active boot disk's host
attachment, in particular SAN boot disks?
A:
The system administrator is responsible for choosing a disk that DRD can use. This
would include any communication with the SAN to assign the disk to a particular
system.
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1-17. Q:
What is the difference between DRD Hot Recovery and Mirror Disk/UX?
A:
Mirror Disk/UX keeps an "always up to date" image of the booted system. Conversely,
DRD provides a "point in time" image. The booted system and the clone may then
diverge due to changes to either one. Keeping the clone unchanged is the Hot Recovery
scenario. Note that DRD is not available for HP-UX 11.11, which limits your options
on those systems.
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1-18. Q:
Since I take a regular root disk and use it to boot another system, can I use the
cloned disk I created with DRD to boot another system?
A:
It is possible to do this, however, factors such as machine personality (e.g., hostname,
IP address, etc.) make this very difficult. HP does not recommend using the cloned disk
to boot another system.
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1-19. Q:
What happens during a clone copy if, for example, /opt/xxxxx is mounted from
/dev/vg01/lvolxxxx? Is the content of /opt/xxxxx copied to the clone or does it
only create its directory?
A:
Only the contents of vg00 are copied. In the above example, the content of /opt/xxxxx
will not be copied to the clone. A system that has the /opt file systems (or any file
system that is patched) not in vg00 is not suitable for use with DRD.
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1-20. Q:
What are the effects of the clone copy on system operation (for example,
performance)?
A:
The I/O of the clone operation will have some impact, particularly if the disk is close to