HP 12000 User Manual page 175

Symptom
VLS performance is being reduced by
frequent tape drive polling.
At reboot, there are spurious critical
FC port failures reported as
notification alerts, usually on every
port. Later, Info notification alerts for
each FC host port are generated,
indicating the FC ports are operating
normally.
After replacing drive 0 in a node, the
system will not boot.
When oversubscription is enabled and
you create enough cartridges in a
storage pool to put your free storage
capacity below the threshold, the pool
may reach critical status. If you then
Possible causes
Windows Removable Storage
Manager service (RSM) polls tape
drives on a frequent basis—every
three seconds in Microsoft Windows
2000, and every second in Windows
Server 2003. Windows' built-in
backup software (NTBACKUP) relies
on the RSM polling to detect media
changes in the tape drive. In SAN
configurations, this RSM polling can
have a significant negative impact on
tape drive performance. For SAN
configurations, HP strongly
recommends disabling RSM polling.
This is expected behavior and does
not indicate a problem.
A blank drive was installed in drive
bay 0.
When you disable oversubscription,
the system does not monitor the
storage pool's capacity, even to check
that it is no longer at a critical level.
The status will not change.
Solution
Refer to the Microsoft website at:
http://support.microsoft.com/
default.aspx?scid=kb;en-us;84241 1
complete the following steps to disable
RSM polling:
1. Install the 1.0.4.0 or later driver.
2. Disable device polling in the system
registry.
Establish a CLI session.
Log into the system as
Administrator.
Run RegEdit and navigate to
the following registry:
H K E Y _ L O C A L _ M A C H I N E \ S Y S T E M \ C u r r e n t C o n t r o l S e t \ S e r v i c e s \ h p l t o .
To disable RSM polling, edit the
AutoRun value found in this key.
A value of 0 (zero) indicates that
polling is disabled; a value of 1
indicates that polling is enabled.
3. After completing steps 1 and 2,
reboot the affected system.
4. Repeat this procedure for every
server visible to tape drives.
IMPORTANT: Adding or removing
tape drives may cause an older driver
.inf file to be reread, which can
re-enable RSM polling. If tape drives
are added or removed, check the
registry for proper configuration. If
necessary, repeat step 2 and 3 above.
To disable polling in the HP SDLT driver
(v3.0.2.0 or later):
1. Open the Device Manager on the
server connected to the tape drive.
2. Double-click an SDLT tape drive.
3. Click the DLT tab.
4. Check Increase performance
by disabling support for
Microsoft Backup Utility.
5. Repeat this procedure for each
server visible to each SDLT tape
drive.
None
If a blank drive is installed in drive bay
0, the system will not boot. To remedy
this, switch the drive located in bay 0
with the drive located in bay 1.
Re-enable oversubscription, set the alert
threshold so that the storage pool is
within the capacity threshold, then wait
for the pool to return to good (green)
VLS Common Issues 175
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