HP-UX System Administrator's Guide: Logical Volume Management (762803-001, March 2014)

Message Text
LVM: vg[nn] pv[nn] No valid MCR, resyncing all mirrored MWC LVs on the PV
Cause
This message appears when you import a volume group from a previous release of HP-UX. The
format of the MWC changed at HP-UX 11i Version 3, so if the volume group contains mirrored
logical volumes using MWC, LVM converts the MWC at import time. It also performs a complete
resynchronization of all mirrored logical volumes, which can take substantial time.
Recommended Action
None.
Message Text
LVM: vg 64 0xnnnnnn: Unable to register
for event notification on device 0xnnnnnnnn (1)
Cause
This message can be displayed on the first system boot after upgrading to HP-UX 11i Version 3.
It is a transient message caused by updates to the I/O configuration. Later in the boot process,
LVM registers for event notification again, and succeeds.
Recommended Action
None.
Message Text
LVM: WARNING: Snapshot LV (VG mmm 0x00n000, LV Number: p) threshold value reached.
Please increase the number of pre-allocated extents for this snapshot LV
Cause
These are the possible causes:
1. This message is generated when the number of extents remaining in a space-efficient snapshot
logical volume’s pre-allocated pool falls beyond a certain internally computed threshold. The
pre-allocated extents of the space-efficient snapshot are consumed as a result of writes either
on it’s successor logical volume on the snapshot tree or on the snapshot itself. This message
is displayed so that the user is informed that further unsharing of data between the snapshot
and its successors might end up depleting the extents in the pre-allocated pool and lead to
the snapshot and its predecessors being marked as inoperative.
2. Beginning with the HP-UX 11i v3 September 2010 Update, you can enable LVM to
automatically increase the number of pre-allocated extents when the threshold is reached. If
this feature is enabled, this message will be logged every time LVM tries to increase
pre-allocated extents.
Recommended Action
1. Increase the number of pre-allocated extents for the space-efficient snapshot using the
lvextend command to prevent the snapshot from becoming inoperative.
2. If there is no error reported following this warning message, this message can be ignored. If
there is an error, please follow the relevant recommended action for the error. If this error is
seen more frequently, you can either increase the number of pre-allocated extends and/or
threshold value, as appropriate. Please see the LVM Snapshot Logical Volumes white paper
for more details.
F.16 Log Files and Trace Files: /var/adm/syslog/syslog.log 189