Configuration Device Mapper Multipath for Linux, 167 | Dell MD3220

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Configuration: Device Mapper Multipath for Linux

Overview

The MD3200 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 MD3200 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 MD3200 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 MD3200 and MD3220 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 MD3220, MD3200 owner manual Configuration Device Mapper Multipath for Linux, 167

Contents

Dell PowerVault MD3200 and MD3220 Storage Arrays May Contents Planning MD3200 Series Storage Array Terms and Concepts Cache Functions and Features Virtual Disk Operations Limit Out-of-Band and In-Band Management Configuring Alert Notifications Managing Host Port Identifiers Enabling or Disabling the Event Monitor Host-to-Virtual Disk Mapping Configuring Hot Spare Physical DisksPhysical Disk Security with Self Encrypting 125 Creating a Snapshot Virtual Disk UsingSnapshot Using the Simple Path 137 122 154 145Re-creating a Snapshot Virtual Disk 152 Creating a Virtual Disk Copy for an Mscs 161 Using DM Multipathing Devices 168159 160 178 Media Errors and Unreadable Sectors 187Downloading RAID Controller and Nvsram 177 206 Power Supply/Cooling Fan Module 204197 202 221 Recovering From an Unresponsive Storage 229217 Storage Array Support Data 220 Troubleshooting External Connections Safety First-For you and Your ArrayTroubleshooting Storage Array Startup Failure Troubleshooting Loss of Communication 253 About This Document Introduction Dell PowerVault Modular Disk Storage Manager Dell PowerVault MD3200 Series Storage Array 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 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 Function RAID Controller Module Connectors and Features Item Component Function Component Function RAID Controller Module-Additional FeaturesBattery Backup Unit Event Description System Password ResetStorage Array Thermal Shutdown Shutdown Threshold Type Write-Through Cache Cache Functions and FeaturesCache Mirroring Write-Back Cache Physical Disks, Virtual Disks, and Disk Groups Planning MD3200 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 RAID LevelsVirtual Disk States RAID RAID Level Usage RAID Background Initialization Segment SizeVirtual Disk Operations Virtual Disk Initialization Cycle Time Consistency CheckMedia Verification Segment Size Migration Disk Group OperationsVirtual Disk Operations Limit RAID Level Migration Disk Group Expansion Virtual Disk Capacity Expansion Disk Group Operations Limit RAID Background Operations PriorityDisk Group Defragmentation Disk Migration Virtual Disk Migration and Disk Roaming Planning MD3200 Series Storage Array Terms and Concepts Disk Roaming Advanced Features Snapshot Virtual Disks Host Server-to-Virtual Disk MappingHost Types Snapshot Repository Virtual Disk Target Virtual Disk Virtual Disk RecoveryVirtual Disk Copy Source Virtual Disk Multi-Path Software Using Snapshot and Disk Copy Together Virtual Disk Ownership Preferred and Alternate Controllers and Paths Load Balancing Monitoring MD3200 Series System Performance Performance Monitor Table Description Column Headings For more information, see the online help topics Planning MD3200 Series Storage Array Terms and Concepts User Interface Configuration Overview Enterprise Management Window Array Management Window Inheriting the System SettingsSelect Tools→ Inherit System Settings Select Inherit system settings for color and font 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 AMW, select Storage Array→ Blink→ Storage Array Locating Storage Arrays Name/Rename Storage Arrays dialog appears Naming or Renaming Storage Arrays Type the New password Setting a PasswordPassword Viewing Storage Array Connections Password Guidelines Select Edit→ Remove→ Storage Array Adding/Editing a Comment to an Existing Storage ArrayRemoving Storage Arrays Select Edit→ Comment Failover Alert Display Enabling Premium Features Changing the Enclosure Order in the Physical Pane Changing the Cache Settings on the Storage ArrayChanging Expansion Enclosure ID Number Select All storage arrays Configuring Alert NotificationsSelect Configure Alerts AMW, select Storage Array→ Change→ Enclosure Order Configuring E-mail Alerts Configuration About Your Storage Array Configuring Snmp Alerts Battery Settings Setting the Storage Array RAID Controller Module Clocks Configuration About Your Storage Array Configuration Event Monitor Linux Enabling or Disabling the Event MonitorWindows Configuring Host Access Configuration About Your Host Select Mappings→ Define→ Host Using the Mappings TabDefining a Host Configuration About Your Host Select Mappings→ Remove Removing Host AccessManaging Host Groups Creating a Host Group Select Mappings→ Move Moving a Host to a Different Host GroupAdding a Host to a Host Group Removing a Host From a Host Group Host Topology Removing a Host Group Windows Starting or Stopping the Host Context AgentLinux Click Action→ Start Data Path Protection Add Host Port Identifier dialog appears Managing Host Port Identifiers Configuration About Your Host Creating Disk Groups and Virtual Disks Configuration Disk Groups and Virtual Disks Introduction Create Disk Group window is displayed Creating Disk Groups Configuration Disk Groups and Virtual Disks Creating Virtual Disks Locating a Disk Group Configuration Disk Groups and Virtual Disks Changing the Virtual Disk Modification Priority Map later Using Mappings View Changing the Virtual Disk Cache Settings 100 101 Changing the Segment Size of a Virtual Disk 102 Changing the I/O TypeSelect Virtual Disk→ Change→ Segment Size 103 Choosing an Appropriate Physical Disk TypeFile system typical Database Multimedia Custom 104 Physical Disk Security with Self Encrypting Disk 105 106 Creating a Security Key 107 Click Create Key 108 Changing a Security KeyConfirm Change Security Key window is displayed 109 Saving a Security KeyClick Change Key 110 Unlocking Secure Physical Disks 111 Configuring Hot Spare Physical DisksErasing Secure Physical Disks 112 Select Physical disk→ Hot Spare CoverageHot Spare Physical Disk Options window is displayed 113 Hot Spares and RebuildGlobal Hot Spares Click Unassign 114 Hot Spare OperationHot Spare Drive Protection Criteria for Enclosure Loss Protection RAID Level Enclosure Loss Protection115 116 Host-to-Virtual Disk Mapping 117 Creating Host-to-Virtual Disk Mappings 118 Modifying and Removing Host-to-Virtual Disk Mapping 119 Changing Controller Ownership of the Virtual Disk 120 Removing Host-to-Virtual Disk MappingSelect Virtual Disk→ Change→ Ownership/Preferred Path 121 Select Disk Group→ Change→ Ownership/Preferred Path 122 Restricted MappingsChanging the RAID Level of a Disk Group Select Disk Group→ Change→ RAID Level 123 124 125 Changing the RAID Level of a Disk Group 126 Storage Partitioning 127 128 Disk Group and Virtual Disk ExpansionSelect Disk Group→ Add Free Capacity Physical Disks 129 Using Free CapacityUsing Unconfigured Capacity Virtual Disk Expansion Non-Exportable Components Disk Group MigrationExport Disk Group Exporting a Disk Group 131 Import Disk GroupImporting a Disk Group 132 Storage Array Media ScanNon-Importable Components 133 Changing Media Scan Settings 134 Suspending the Media Scan 135 Configuration Premium Feature- Snapshot Virtual Disks 136 Creating a Snapshot Virtual Disk Using the Simple Path 137 About the Simple Path 138 139 140 Creating a Snapshot Virtual Disk Using the Advanced PathAbout the Advanced Path 141 142 143 Creating the Snapshot Using the Advanced Path 144 Specify Virtual Disk Parameters window is displayed 145 Specifying Snapshot Virtual Disk Names 146 Snapshot Repository Capacity 147 148 Click Add Physical DisksAdd Physical Disks window closes 149 Re-creating Snapshot Virtual DisksSelect Virtual Disk→ Snapshot→ Re-create 150 Disabling a Snapshot Virtual Disk 151 Preparing Host Servers to Re-create a Snapshot Virtual Disk 152 Re-creating a Snapshot Virtual DiskSelect Virtual Disk → Snapshot→ Re-create 153 Configuration Premium Feature- Virtual Disk Copy 154 Creating a Virtual Disk Copy for an Mscs Shared Disk 155 Virtual Disk Read/Write PermissionsVirtual Disk Copy Restrictions 156 Creating a Virtual Disk Copy 157 Before you BeginVirtual Disk Copy and Modification Operations Create Copy Wizard 158 Preferred RAID Controller Module OwnershipFailed RAID Controller Module Failed Virtual Disk Copy 159 Copy ManagerCopying the Virtual Disk 160 Storage Array Performance During Virtual Disk Copy 161 Setting Copy PriorityStopping a Virtual Disk Copy Select Change→ Copy Priority 162 Recopying a Virtual DiskPreparing Host Servers to Recopy a Virtual Disk 163 Recopying the Virtual Disk 164 Removing Copy PairsSelect Copy→ Re-Copy 165 166 167 Configuration Device Mapper Multipath for Linux 168 Using DM Multipathing DevicesPrerequisite Steps 169 Device Mapper Configuration StepsScan for Newly Added Virtual Disks 170 171 Create a New fdisk Partition on a Multipath Device NodeAdd a New Partition to Device Mapper Important Information About Special Partitions Create a File System on a Device Mapper PartitionMount a Device Mapper Partition Ready for Use 173 Device Mapper Commands Descriptions 174 Limitations and Known Issues QuestionAnswer Troubleshooting175 176 177 Downloading RAID Controller and Nvsram Packages 178 Downloading Both RAID Controller and Nvsram Firmware 179 Click Transfer 180 Downloading Only Nvsram Firmware 181 Select Tools→ Upgrade RAID Controller Module FirmwareUpgrade RAID Controller Module Firmware window appears 182 183 Downloading Physical Disk Firmware 184 185 AMW, select Advanced→ Maintenance→ Download→ EMM FirmwareDownloading MD1200 Series Expansion Module EMM Firmware Download Environmental EMM Firmware dialog appears 186 Self-Monitoring Analysis and Reporting Technology Smart 187 Media Errors and Unreadable Sectors 188 189 Management Installing Array ComponentsRecommended Tools 190 Installing the Front BezelFront Bezel Optional Removing the Front Bezel 191 Safety Models AMT, E03J, and E04JHard Drives Removing a Drive Blank 192 Installing a Drive BlankRemoving a Hard Drive 193 Removing and Installing a Hard Drive 194 Installing a Hard Drive 195 Removing a Hard Drive From a Hard-Drive Carrier 196 197 Installing a Hard Drive Into a Drive CarrierRAID Controller Module Removing a RAID Controller Module Blank 198 Installing a RAID Controller Module Blank 199 Removing a RAID Controller Module 200 Installing a RAID Controller ModuleOpening the RAID Controller Module 201 Closing the RAID Controller Module 202 RAID Controller Module Backup Battery UnitRemoving the RAID Controller Module Backup Battery Unit 203 Installing the RAID Controller Module Backup Battery Unit 204 Power Supply/Cooling Fan ModuleRemoving a Power Supply/Cooling Fan Module 205 Installing a Power Supply/Cooling Fan Module 206 Control PanelRemoving the Control Panel 207 208 Installing the Control Panel 209 BackplaneRemoving the Backplane 210 17. Removing and Installing the Backplane-PowerVault MD3220 16. Removing and Installing the Backplane-PowerVault MD3200 212 Installing the Backplane 213 Management Firmware InventoryViewing the Firmware Inventory 214 Management System Interfaces Microsoft ServicesVirtual Disk Service Volume Shadow-Copy Service 216 217 Troubleshooting Your Storage Array SoftwareStart-Up Routine Device Health Conditions Status Icon Description On the Setup tab, select Manage a Storage Array218 Additional Status Icons Description 219 220 Storage Array Support Data 221 Automatically Collect the Support Bundle DataEnter the Execution summary 222 Collecting the Physical Disk DataEvent Log 223 Recovery Guru 224 Storage Array ProfileSelect Storage Array→ View→ Profile 225 226 Viewing the Logical AssociationsViewing the Physical Associations 227 Finding Nodes 228 Using Go ToSelect Find all free capacity nodes Click Find Next 229 Recovering From an Unresponsive Storage Array Condition 230 231 232 Locating a Physical Disk 233 Locating an Expansion EnclosureSelect Physical Disk→ Blink→ Expansion Enclosure 234 Capturing the State Information 235 SMrepassist Utility 236 Recovering From an Unidentified Storage ArrayUnidentified Devices 237 238 239 Starting or Restarting the Host Context Agent Software 240 241 Troubleshooting Your ArrayTroubleshooting Loss of Communication Troubleshooting External Connections 242 Troubleshooting Power Supply/Cooling Fan Module 243 Troubleshooting Array Cooling ProblemsTroubleshooting Expansion Enclosure Management Modules 244 Troubleshooting RAID Controller Modules 245 246 Troubleshooting Hard Drives 247 Troubleshooting Array and Expansion Enclosure Connections 248 Troubleshooting a Wet Storage Array 249 Troubleshooting a Damaged ArrayConditions Critical Conditions ECC ErrorsPCI Errors Invalid Storage Array 251 Noncritical Conditions 252 Click All Support from Support menu Getting HelpContacting Dell Visit support.dell.com 254 255 Index 256 257 258 259 260