Seagate ST34572WC Specifications

When Good Disks Go Bad: Dealing with Disk Failures under LVM Abstract ...

For example, the following shows a successful read of the first 64 megabytes of the disk: # dd if=/dev/rdsk/c0t5d0 of=/dev/null bs=1024k count=64 64+0

4. Gathering Information about a Failing Disk Once you know which disk is failing, you can decide how to deal with it. You can choose to remove the di

extents are mapped to an unavailable physical volume. The lvdisplay command shows ’???’ for the physical volume if it is unavailable. The problem wit

5. Removing the Disk If you have a copy of the data on the failing disk, or you can move the data to another disk, you can choose to remove the disk f

physical extents on that disk to any other disks in the volume group, subject to any mirroring allocation policies. For example: # pvmove pvname You

# vgreduce -f vgname # mv /etc/lvmtab /etc/lvmtab.save # vgscan –v This completes the procedure for removing the disk from your LVM configuration. I

6. Replacing the Disk If you decide to replace the disk, you must perform a five-step procedure. How you perform each step depends on the information

3. To kill processes using the logical volume, enter the following command: # fuser –ku /dev/vgname/lvname 4. Then try to unmount the file system

Step 2: Replacing the Faulty Disk If the disk is hot-swappable, you can replace it without powering down the system. Otherwise, power down the system

Step 5: Restoring Lost Data to the Disk This final step can be a straightforward resynchronization for mirrored configurations, or a recovery of data

Scenario 1: Best Case ...19 Scenario 2:

Root: lvol3 on: /dev/dsk/c0t5d0 Swap: lvol2 on: /dev/dsk/c0t5d0 Dump: lvol2 on: /dev/dsk/c0t5d0, 0 # pvdisplay –v /dev/dsk/c2t

# fuser -u /dev/vg01/lvol1 /dev/vg01/lvol1: 27815c(root) 27184c(root) # ps -fp27815 -p27184 UID PID PPID C STIME TTY TIME COMMA

Disk Replacement Flowchart The following flowchart summarizes the disk replacement process. 22

Conclusion In your role as system manager, you will encounter disk failures. LVM can lessen the impact of those disk failures, enabling you to configu

Appendix A: Procedures This section contains details on some of the procedures described earlier. Mirroring the Root Volume on PA-RISC Servers To set

# lvextend –m 1 /dev/vg00/lvol5 /dev/dsk/c2t15d0 # lvextend –m 1 /dev/vg00/lvol6 /dev/dsk/c2t15d0 # lvextend –m 1 /dev/vg00/lvol7 /dev/dsk/c2t15d0 # l

Mirroring the Root Volume on Integrity Servers The procedure to mirror the root disk on Integrity servers is similar to the procedure for PA-RISC serv

# mkboot –e –l /dev/rdsk/c2t1d0 6. Update the autoboot file in the EFI partition. a. Create an AUTO file in the current directory. If you expect

11. Add a line to /stand/bootconf for the new boot disk using vi or another text editor: # vi /stand/bootconf l /dev/dsk/c2t1d0s2 where l denotes LV

Appendix B: LVM Error Messages This appendix lists some of the warning and error messages reported by LVM. For each message, the cause is listed, and

Abstract This white paper discusses how to deal with disk failures under the HP-UX Logical Volume Manager (LVM). It is intended for system administrat

Act PV 1 Max PE per PV 4350 VGDA 2 PE Size (Mbytes) 4

Cause: LVM OLR is not completely installed. Both the LVM command and kernel components are required to enable LVM OLR. In this case, the command patc

Detach the physical volume or deactivate the volume group before attempting to restore the physical volume. If there is reason to believe that the dat

vgchange: Couldn't set the unique id for volume group "/dev/vgname" Cause: There are multiple LVM group files with the same minor numb

Warning: couldn't query physical volume "pvname": The specified path does not correspond to physical volume attached to this volume gr

Syslog Error Messages LVM: VG 64 0x010000: Data in one or more logical volumes on PV 188 0x072000 was lost when the disk was replaced. This occurred b

For more information To learn more about LVM and HP-UX system administration, refer to the following documents on the HP documentation website http://

1. Preparing for Disk Recovery Forewarned is forearmed. Knowing that hard disks will fail eventually, you can take some precautionary measures to mini

# swlist -l fileset | grep -i mirror LVM.LVM-MIRROR-RUN B.11.23 LVM Mirror The process of mirroring is usually straightforward, and can be easily ac

reinstall a minimal system, restore a backup, and be back online within three hours of diagnosis and replacement of hardware. Three disks in the root

2. Recognizing a Failing Disk The guidelines in the previous section will not prevent disk failure on your system. Assuming you follow all the recomme

LVM Command Errors Sometimes LVM commands, such as vgdisplay, return an error suggesting that a disk has problems. For example: # vgdisplay –v | more

3. Confirming Disk Failure Once you suspect a disk has failed or is failing, make certain that the suspect disk is indeed failing. Replacing or removi