Have the engineer replace the faulty disk, no need to reboot, you have hot swap disks.
[Step 1.2]
Restore the LVM configuration/headers onto the new disk from your backup
of the LVM configuration:
# vgcfgrestore -n [volume group name] /dev/rdsk/cXtYdZ
Where X is the 'card instance number' of the SCSI bus attached to
that card. Y is the 'SCSI ID' of the disk (or array controller, in
the case of an array), and Z is the 'LUN number' (typically 0 for a
non-array type disk). Note that if the HP Customer Engineer replaces
the disk at the same address, the device file name will not change.
In that case the name will be what it was prior to the replacement.
For our example:
# vgcfgrestore -n /dev/vg00 /dev/rdsk/c0t4d0
[Step 1.3]
Reactivate the volume group (VG) so that the new disk can be attached,
since it wasn't configured in at boot time:
# vgchange -a y [volume group name]
For our example, the volume group vg00 will already be activated, but
it will not know of the replaced disk; therefore, this step is still
required so that LVM will now know that the disk is again available:
# vgchange -a y /dev/vg00
The vgchange command will activate each specified volume group and all
associated physical and logical volumes for read-write access. In the case
of
vg00,it would initially have been activated with c0t4d0 in an unknown state.
vgchange tells vg00 to look again at c0t4d0, which is now in a known state.
It
is important to remember that even though lvol5 and lvol6 are now active
they
are void of data.
[Step 1.4]
Determine which logical volumes spanned onto that disk. You only need
to recreate and restore data for the volumes that actually touched that
disk. Other LVs in the volume group are still OK.
# pvdisplay -v /dev/dsk/c0tXd0
will show a listing of all the extents on disk lu X, and to what logical
volume they belong. This listing is fairly long, so you might want to
pipe it to more or send it to a file. For our example:
# pvdisplay -v /dev/dsk/c0t4d0 | more
.....
.....
--- Distribution of physical volume ---
LV Name LE of LV PE for LV
/dev/vg00/lvol5 50 50
/dev/vg00/lvol6 245 245
.....
.....
From this we can see that logical volumes /dev/vg00/lvol5 and
/dev/vg00/lvol6 have physical extents on this disk, but /dev/vg00/lvol1
through /dev/vg00/lvol4 don't, so we will need to recreate and restore
lvol5 and lvol6 only.
Note: Even though lvol5 was also in part on another disk drive, it
will need to be treated as if the entire lvol was lost, not just
the part on c0t4d0.
[Step 1.5]
Restore the data from your backup onto the replacement disk for
the logical volumes identified in step 1.4. For raw volumes, you can
simply restore the full raw volume using the utility that was used to
create your backup. For file systems, you will need to recreate the
file systems first. For our example:
For HFS:
# newfs -F hfs /dev/vg00/rlvol5
# newfs -F hfs /dev/vg00/rlvol6
For JFS:
# newfs -F vxfs /dev/vg00/rlvol5
# newfs -F vxfs /dev/vg00/rlvol6
Note that we use the raw logical volume device file for the newfs
command. For file systems that had non-default configurations, please
consult the man page of newfs for the correct options.
After a file system has been created on the logical volume mount the
file system under the mount point that it previously occupied. Take
whatever
steps are necessary to prevent your applications or users from accessing the
filesystem until the data has been recovered. Now that the filesystem has
been
created simply restore the data for that file system from backups.
Note: You will need to have recorded how your file systems were
originally created in order to perform this step. The only
critical feature of this step is that the file system be at
least as large as before the disk failure. You can change
other file system parameters, such as those used to tune the
file system's performance.
For the file system case, there is no need to worry about data on the
disk (c0t5d0) that was newer then the data on the tape. The newfs
wiped out all data on the lvol5. For the raw volume access, you may
have to specify your restore utilities over-write option to guarantee
bringing the volume back to a known state.
