HP-UX System Administrator's Guide: Logical Volume Management (762803-001, March 2014)
3.13.4 Hardware Requirements..........................................................................................112
3.14 Hardware Issues............................................................................................................113
3.14.1 Integrating Cloned LUNs..........................................................................................113
4 Troubleshooting LVM...............................................................................115
4.1 Troubleshooting Overview................................................................................................115
4.1.1 Information Collection...............................................................................................115
4.1.2 Consistency Checks..................................................................................................116
4.1.3 Maintenance Mode Boot..........................................................................................116
4.2 I/O Errors.....................................................................................................................117
4.2.1 Recoverable Errors...................................................................................................117
4.2.1.1 Temporarily Unavailable Device..........................................................................118
4.2.1.2 Permanently Unavailable Device.........................................................................118
4.2.2 Nonrecoverable Errors.............................................................................................118
4.2.2.1 Media Errors...................................................................................................119
4.2.2.2 Missing Device When the Volume Group Was Activated......................................119
4.3 Volume Group Activation Failures.....................................................................................119
4.3.1 Quorum Problems with a Nonroot Volume Group........................................................119
4.3.2 Quorum Problems with a Root Volume Group.............................................................120
4.3.3 Version 2.x Volume Group Activation Failures.............................................................120
4.4 Root Volume Group Scanning..........................................................................................122
4.5 LVM Boot Failures...........................................................................................................123
4.5.1 Insufficient Quorum..................................................................................................123
4.5.2 Corrupted LVM Data Structures on Disk......................................................................123
4.5.3 Corrupted LVM Configuration File..............................................................................123
4.6 Problems After Reducing the Size of a Logical Volume.........................................................123
4.7 Disk Troubleshooting and Recovery Procedures...................................................................124
4.7.1 Step 1: Preparing for Disk Recovery............................................................................124
4.7.1.1 Defining a Recovery Strategy..............................................................................124
4.7.1.2 Using LVM Online Disk Replacement (LVM OLR)....................................................125
4.7.1.3 Mirroring Critical Information, Especially the Root Volume Group............................125
4.7.2 Step 2: Recognizing a Failing Disk............................................................................126
4.7.2.1 I/O Errors in the System Log..............................................................................126
4.7.2.2 Disk Failure Notification Messages from Diagnostics.............................................126
4.7.2.3 LVM Command Errors.......................................................................................126
4.7.3 Step 3: Confirming Disk Failure.................................................................................128
4.7.4 Step 4: Determining Action for Disk Removal or Replacement........................................131
4.7.5 Step 5: Removing a Bad Disk....................................................................................134
4.7.5.1 Removing a Mirror Copy from a Disk..................................................................134
4.7.5.2 Removing Mirror Copy from Ghost Disk..............................................................134
4.7.5.3 Moving the Physical Extents to Another Disk........................................................135
4.7.5.4 Removing the Disk from the Volume Group .........................................................135
4.7.6 Step 6: Replacing a Bad Disk (Persistent DSFs)............................................................137
4.7.6.1 Replacing a Mirrored Nonboot Disk...................................................................137
4.7.6.2 Replacing an Unmirrored Nonboot Disk..............................................................139
4.7.6.3 Replacing a Mirrored Boot Disk.........................................................................142
4.7.6.4 Replacing an Unmirrored Boot Disk....................................................................144
4.7.7 Step 7: Replacing a Bad Disk (Legacy DSFs)...............................................................145
4.8 Reporting Problems.........................................................................................................146
5 Support and Other Resources...................................................................149
5.1 New and Changed Information in This Edition....................................................................149
5.2 About this Series.............................................................................................................149
6 Contents