Configuration Device Mapper Multipath for Linux, 185 | Dell MD3600I

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Configuration: Device Mapper Multipath for Linux

Overview

The MD3600i Series storage array uses a Linux operating system software framework, known as Device Mapper (DM), to enable multipath capabilities on Linux Host Servers. The DM multipath functionality is provided by a combination of drivers and utilities. This chapter describes how to use those utilities to complete the process of enabling MD3600i Series storage array on a Linux system.

The Device Mapper technology replaces an earlier, proprietary technology, known as MPP. MPP was used to enable multipathing for the previous MD generation MD3000 Series storage arrays.

NOTE: The required Device Mapper software components are installed on a Linux host server by running the MD3600i Series resource media installation program on the server, and selecting either the Full or Host install option. For detailed installation procedures please refer to the Dell PowerVault MD3600i and MD3620i storage arrays Deployment Guide.

Benefits of using DM Multipath include:

•Detects path failure and re-routes I/O to other available paths

•Revalidates failed paths after path restoration

•Utilizes multiple available paths to maximize performance

•Reconfigures path usage based on path states and error conditions

•Unifies multiple device nodes into a single logical multipath device node

•Indentifies a new multipathed LU and automatically configures a new multipath node

•Provides device name persistency for DM devices under /dev/mapper/

Configuration: Device Mapper Multipath for Linux

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Dell MD3600I, MD3620I owner manual Configuration Device Mapper Multipath for Linux, 185

Contents

Dell PowerVault MD3600i and MD3620i Storage Arrays December Contents Planning RAID Controller Modules Cache Functions and Features Virtual Disk Operations Limit Out-of-Band and In-Band Management Configuring Alert Notifications Enabling or Disabling the Event Monitor Edit, Remove, or Rename Host Topology 107 103Managing Host Port Identifiers 104 126 117130 Host-to-Virtual Disk Mapping 131 145 143146 147 Re-Creating a Snapshot Virtual Disk ContentsCreating a Virtual Disk Copy for Virtual Disk Copy Restrictions Stopping a Virtual Disk Copy 178 Using DM Multipathing Devices 186179 Preparing Host Servers 179 209 Downloading Both RAID Controller210 211 Power Supply/Cooling Fan Module 224 RAID Controller Module Backup Battery Unit 222227 229 237 Recovering From an Unresponsive241 242 Troubleshooting Power 264 Safety First-For you and Your Array 263Troubleshooting Expansion Enclosure Management Modules 265 Troubleshooting a Damaged Array 270 272 Contents About This Document Introduction MD3600i Series Storage Array Dell PowerVault Modular Disk Storage ManagerDell PowerVault Modular Disk Configuration Utility Other Information You May Need Introduction Overview Planning About Your Storage Array Front-Panel Features and Indicators Hardware Features Planning About Your Storage Array Item Indicator, Button, or Icon Description Connector Back-Panel Features and Indicators Hard Drive Indicators Hard-Drive Indicator Patterns Hard-Drive Status Indicator Pattern Condition Power Supply and Cooling Fan Features Power Indicator Codes Item LED Type Icon Description Power Indicator Codes RAID Controller Modules Planning RAID Controller Modules MD3600i Series iSCSI RAID Controller Module RAID Controller Module Connectors and Features Item Component Function Battery Backup Unit RAID Controller Module-Additional FeaturesStorage Array Thermal Shutdown Shutdown Threshold Type System Password Reset Cache Functions and FeaturesCache Mirroring Write-Back Cache Write-Through Cache Physical Disks, Virtual Disks, and Disk Groups Planning MD3600i Series Storage Array Terms and Concepts Physical Disk States Physical Disks Virtual Disks and Disk Groups Self-Monitoring Analysis and Reporting Technology RAID Controller Virtual Disk States Description Virtual Disk States RAID Level Usage RAID Levels RAID Virtual Disk Operations Segment SizeVirtual Disk Initialization Background Initialization Media Verification Consistency CheckCycle Time Foreground Initialization RAID Level Migration Disk Group OperationsVirtual Disk Operations Limit Disk Group Expansion Segment Size MigrationVirtual Disk Capacity Expansion Disk Group Operations Limit RAID Background Operations PriorityDisk Group Defragmentation Disk Migration Virtual Disk Migration and Disk Roaming Planning MD3600i Series Storage Array Terms and Concepts Host Server-to-Virtual Disk Mapping Disk Roaming Host Types Advanced Features Snapshot Repository Virtual Disk Snapshot Virtual Disks Target Virtual Disk Virtual Disk CopySource Virtual Disk Multi-Path Software Virtual Disk RecoveryUsing Snapshot and Disk Copy Together Virtual Disk Ownership Preferred and Alternate Controllers and Paths Load Balancing Monitoring MD3600i Series System Performance Planning MD3600i Series Storage Array Terms and Concepts Performance Monitor Table Description Column Headings Planning MD3600i Series Storage Array Terms and Concepts User Interface Configuration Overview Enterprise Management Window Array Management Window Inheriting the System Settings Configuration Overview Out-of-Band Management Configuration About Your Storage ArrayOut-of-Band and In-Band Management In-Band Management Storage ArraysAdding Storage Arrays Select Edit→ Add Storage Array Automatic Discovery of Storage ArraysManual Addition of a Storage Array Setting Up Your Storage Array Configuration About Your Storage Array Locating Storage Arrays AMW Setup tab, select Rename Storage ArrayNaming or Renaming Storage Arrays AMW, select Storage Array→ Blink→ Storage Array Name/Rename Storage Arrays dialog appears Setting a Password Password Guidelines PasswordType the New password Select Edit→ Comment Viewing Storage Array ConnectionsAdding/Editing a Comment to an Existing Storage Array Select Edit→ Remove→ Storage Array Enabling Premium FeaturesRemoving Storage Arrays Displaying Failover Alert Changing the Cache Settings on the Storage Array AMW, select Storage Array→ Change→ Enclosure Order Changing Expansion Enclosure ID NumbersChanging the Enclosure Order in the Physical Pane Configuring E-mail Alerts Configuring Alert NotificationsSelect Configure Alerts Select All storage arrays Configuration About Your Storage Array Configuration About Your Storage Array Configuring Snmp Alerts Battery Settings Setting the Storage Array RAID Controller Module Clocks Changing the iSCSI Target Authentication Configuration Using iSCSISelect Manage iSCSI Settings Enter the Target Chap secret Select the Mutual Authentication tab Entering Mutual Authentication PermissionsClick OK in the Manage iSCSI Settings window Creating Chap Secrets Target Chap Secret Initiator Chap SecretValid Characters for Chap Secrets Valid Ascii Characters for Chap Secrets Changing the iSCSI Target Identification Changing the iSCSI Target Discovery SettingsSelect the Target Identification tab Select the Target Discovery tab Configuring the iSCSI Host Ports Configuration Using iSCSI Advanced iSCSI Host Port Settings Description Advanced iSCSI Host Ports Settings Viewing or Ending an iSCSI Session Click Set Baseline Viewing iSCSI Statistics and Setting Baseline Statistics Mappings→ Move Edit, Remove, or Rename Host Topology Configuration Event Monitor Linux Enabling or Disabling the Event MonitorWindows Configuring Host Access Configuration About Your Host Using the Mappings Tab Select Mappings→ Define→ Host Defining a Host Select Mappings→ Remove Removing Host Access Creating a Host Group Managing Host GroupsSelect Mappings→ Define→ Host Group Adding a Host to a Host Group Removing a Host From a Host Group Moving a Host to a Different Host GroupSelect Mappings→ Move Move Host Confirmation dialog appears 101 Removing a Host GroupHost Topology Linux Starting or Stopping the Host Context AgentWindows Click Action→ Start 103 Data Path Protection 104 Managing Host Port IdentifiersAdd Host Port Identifier dialog appears 105 106 107 Configuration Disk Groups and Virtual DisksCreating Disk Groups and Virtual Disks 108 Creating Disk GroupsIntroduction Create Disk Group window is displayed 109 Creating Virtual Disks Locating a Disk Group 111 112 Changing the Virtual Disk Modification Priority 113 Changing the Virtual Disk Cache Settings 114 115 Changing the Segment Size of a Virtual DiskSelect Virtual Disk→ Change→ Segment Size 116 Changing the I/O TypeFile system typical Database Multimedia Custom 117 Choosing an Appropriate Physical Disk TypePhysical Disk Security with Self Encrypting Disk 118 119 Save Security Key File Validate Security Key Unlock Drives 120 Creating a Security Key 121 122 Changing a Security KeyClick Create Key 123 Confirm Change Security Key window is displayed 124 Saving a Security KeyClick Change Key 125 Validate Security KeyUnlocking Secure Physical Disks 126 Configuring Hot Spare Physical DisksErasing Secure Physical Disks 127 Select Physical disk→ Hot Spare CoverageHot Spare Physical Disk Options window is displayed Global Hot Spares Hot Spares and RebuildClick Unassign 128 129 Hot Spare OperationHot Spare Drive Protection Criteria for Enclosure Loss Protection RAID Level Enclosure Loss Protection130 131 Host-to-Virtual Disk Mapping 132 Creating Host-to-Virtual Disk Mappings 133 Modifying and Removing Host-to-Virtual Disk Mapping 134 Changing Controller Ownership of the Virtual Disk 135 Removing Host-to-Virtual Disk MappingSelect Virtual Disk→ Change→ Ownership/Preferred Path 136 Select Disk Group→ Change→ Ownership/Preferred Path Changing the RAID Level of a Disk Group Restricted MappingsSelect Disk Group→ Change→ RAID Level 137 138 139 140 141 Changing the RAID Level of a Disk GroupStorage Partitioning 142 143 Disk Group and Virtual Disk ExpansionSelect Disk Group→ Add Free Capacity Physical Disks Using Unconfigured Capacity Using Free CapacityVirtual Disk Expansion 144 Export Disk Group Disk Group MigrationExporting a Disk Group Non-Exportable Components 146 Import Disk GroupImporting a Disk Group 147 Storage Array Media ScanNon-Importable Components 148 Changing Media Scan Settings 149 Suspending the Media Scan 150 151 Configuration Premium Feature- Snapshot Virtual Disks 152 153 Creating a Snapshot Virtual Disk Using the Simple PathAbout the Simple Path 154 155 156 Creating a Snapshot Virtual Disk Using the Advanced PathAbout the Advanced Path 157 158 159 Specify Virtual Disk Parameters window is displayed Creating the Snapshot Using the Advanced PathAutomatic Map later with Storage Partition 160 161 Specifying Snapshot Virtual Disk Names 162 163 Snapshot Repository Capacity 164 Click Add Physical Disks 165 Add Physical Disks window closes Disabling a Snapshot Virtual Disk Re-Creating Snapshot Virtual DisksSelect Virtual Disk→ Snapshot→ Re-create 166 167 Preparing Host Servers to Re-Create a Snapshot Virtual Disk 168 Re-Creating a Snapshot Virtual DiskSelect Virtual Disk → Snapshot→ Re-create 169 Configuration Premium Feature- Virtual Disk Copy 170 Creating a Virtual Disk Copy for an Mscs Shared Disk 171 Virtual Disk Read/Write Permissions 172 Virtual Disk Copy RestrictionsCreating a Virtual Disk Copy 173 Before you BeginVirtual Disk Copy and Modification Operations Create Copy Wizard Preferred RAID Controller Module OwnershipFailed Virtual Disk Copy 174 Copy Manager Failed RAID Controller ModuleCopying the Virtual Disk 175 176 177 Setting Copy PriorityStorage Array Performance During Virtual Disk Copy 178 Stopping a Virtual Disk CopySelect Change→ Copy Priority 179 Recopying a Virtual DiskPreparing Host Servers to Recopy a Virtual Disk 180 Recopying the Virtual Disk 181 Removing Copy PairsSelect Copy→ Re-Copy 182 183 184 185 Configuration Device Mapper Multipath for Linux 186 Using DM Multipathing DevicesPrerequisites 187 Device Mapper Configuration Steps 188 Scan for Newly Added Virtual Disks 189 Create a New fdisk Partition on a Multipath Device Node Dev/mapper/mpathxpy Add a New Partition to Device MapperDev/mapper/mpathx-party Dev/mapper/mpathxparty Create a File System on a Device Mapper Partition Linux Host Server Reboot Best PracticesMount a Device Mapper Partition Ready For Use 192 Useful Device Mapper Commands DescriptionImportant Information About Special Partitions 193 Limitations and Known Issues Question Answer Troubleshooting194 195 196 197 Downloading RAID Controller and Nvsram Packages 198 Downloading Both RAID Controller and Nvsram Firmware 199 Click Transfer 200 201 Downloading Only Nvsram Firmware 202 203 Downloading Physical Disk Firmware 204 Downloading MD1200 Series Expansion Module EMM Firmware AMW, select Advanced→ Maintenance→ Download→ EMM FirmwareDownload Environmental EMM Firmware dialog appears 205 206 Self-Monitoring Analysis and Reporting Technology Smart 207 Media Errors and Unreadable Sectors 208 209 Management Installing Array ComponentsRecommended Tools Front Bezel Optional Installing the Front BezelRemoving the Front Bezel 210 Hard Drives Safety Models AMT, E03J, and E04JRemoving a Drive Blank 211 212 Installing a Drive BlankRemoving a Hard Drive 213 Removing and Installing a Hard Drive 214 Installing a Hard Drive 215 Removing a Hard Drive From a Hard-Drive Carrier 216 RAID Controller Module Installing a Hard Drive Into a Drive CarrierRemoving a RAID Controller Module Blank 217 218 Installing a RAID Controller Module Blank 219 Removing a RAID Controller Module 220 Installing a RAID Controller ModuleOpening the RAID Controller Module 221 Closing the RAID Controller Module 222 RAID Controller Module Backup Battery UnitRemoving the RAID Controller Module Backup Battery Unit 223 Installing the RAID Controller Module Backup Battery Unit 224 Power Supply/Cooling Fan ModuleRemoving a Power Supply/Cooling Fan Module 225 226 Installing a Power Supply/Cooling Fan Module 227 Control PanelRemoving the Control Panel 228 Installing the Control Panel 229 BackplaneRemoving the Backplane 230 17. Removing and Installing the Backplane-PowerVault MD3620i 16. Removing and Installing the Backplane-PowerVault MD3600i 232 Installing the Backplane 233 Management Firmware InventoryViewing the Firmware Inventory 234 Virtual Disk Service Microsoft ServicesVolume Shadow-Copy Service Management System Interfaces 236 Start-Up Routine Troubleshooting Your Storage Array SoftwareDevice Health Conditions 237 Status Icon Description On the Setup tab, select Manage a Storage Array238 Additional Status Icons Description 239 240 Automatically Collect the Support Bundle Data Storage Array Support DataEnter the Execution summary 241 242 Retrieving Trace Buffers 243 244 Collecting Physical Disk DataCollect Physical Disk Data window is displayed 245 Event Log Storage Array Profile Recovery GuruSelect Storage Array→ View→ Profile 246 247 248 Viewing the Logical AssociationsViewing the Physical Associations 249 Finding Nodes Select Find all free capacity nodes Using Go ToClick Find Next 250 251 Recovering From an Unresponsive Storage Array Condition 252 253 254 Locating a Physical Disk 255 Locating an Expansion EnclosureSelect Physical Disk→ Blink→ Expansion Enclosure 256 Capturing the State Information 257 SMrepassist Utility 258 Recovering From an Unidentified Storage ArrayUnidentified Devices 259 260 261 Starting or Restarting the Host Context Agent Software 262 Troubleshooting Loss of Communication Troubleshooting Your ArrayTroubleshooting External Connections 263 264 Troubleshooting Power Supply/Cooling Fan Module 265 Troubleshooting Array Cooling ProblemsTroubleshooting Expansion Enclosure Management Modules 266 Troubleshooting RAID Controller Modules 267 268 Troubleshooting Hard Drives 269 Troubleshooting Array and Expansion Enclosure ConnectionsTroubleshooting a Wet Storage Array 270 Troubleshooting a Damaged Array Conditions ECC ErrorsInvalid Storage Array 271 Critical Conditions PCI ErrorsNoncritical Conditions 272 Contacting Dell Getting HelpVisit support.dell.com Click All Support from Support menu 274 275 Index 276 277 278 279 Smart 280 281 282