Configuration Device Mapper Multipath for Linux, 179 | 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.

NOTE: 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, see the Dell PowerVault MD3200 and MD3220 storage arrays Deployment Guide at support.dell.com/manuals.

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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Image 179

Dell MD3220, MD3200 owner manual Configuration Device Mapper Multipath for Linux, 179

Contents

Dell PowerVault MD3200 and MD3220 Storage Arrays Page Contents Cache Functions and Features RAID Controller Module Connectors Virtual Disk Operations Limit Out-of-Band and In-Band Management Configuring Alert Notifications Creating Disk Groups and Virtual Disks Enabling or Disabling the Event MonitorManaging Host Port Identifiers Host-to-Virtual Disk Mapping Configuring Hot Spare Physical DisksPhysical Disk Security with Self 131 126129 130 151 Creating a Snapshot Virtual Disk Using 142Creating a Snapshot Virtual Disk Using 146 165 160161 Types of Virtual Disk Copies 164 179 Using DM Multipathing Devices 180174 176 203 Self-Monitoring Analysis and Reporting201 202 221 RAID Controller Module Backup Battery Unit 214Power Supply/Cooling Fan Module 216 218 Collecting the Physical Disk Data 234 Recovering From an Unresponsive Storage 241232 233 Troubleshooting a Damaged Array 261 Safety First-For you and Your Array 253Troubleshooting Power Supply/Cooling 254 Troubleshooting Expansion Enclosure Getting Help Contacting Dell Index Contents About This Document Introduction MD3200 Series Storage Array Dell PowerVault Modular Disk Storage ManagerOther Information you May Need Introduction 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 and Features 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 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 AMW, select Storage Array→ Monitor Performance Monitoring MD3200 Series System Performance Click Settings Performance Monitor Table Description Column Headings Planning MD3200 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 AMW, select Storage Array→ Blink→ Storage Array Locating Storage Arrays Name/Rename Storage Arrays dialog is displayed AMW Setup tab, select Rename Storage ArrayNaming 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 Configuration About Your Storage Array Battery Settings Setting the Storage Array RAID Controller Module Clocks 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 is displayed 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 100 Map later Using Mappings ViewChanging the Virtual Disk Modification Priority 101 Changing the Virtual Disk Cache Settings 102 103 Changing the Segment Size of a Virtual Disk 104 Changing the I/O TypeSelect Virtual Disk→ Change→ Segment Size 105 Choosing an Appropriate Physical Disk TypeFile system typical Database Multimedia Custom 106 Physical Disk Security with Self Encrypting Disk 107 Shows how to interpret the security status of a disk group 108 Creating a Security Key 109 Click Create Key 110 Changing a Security KeyConfirm Change Security Key window is displayed 111 Saving a Security KeyClick Change Key 112 Validate Security Key 113 Unlocking Secure Physical DisksErasing Secure Physical Disks 114 Configuring Hot Spare Physical DisksSelect Physical disk→ Hot Spare Coverage 115 Hot Spares and RebuildHot Spare Physical Disk Options window is displayed Click Unassign 116 Global Hot SparesHot Spare Operation Hot Spare Drive Protection 117 Enclosure Loss Protection Criteria for Enclosure Loss Protection RAID Level 118 119 Host-to-Virtual Disk MappingCreating Host-to-Virtual Disk Mappings 120 121 Modifying and Removing Host-to-Virtual Disk Mapping 122 Changing Controller Ownership of the Virtual DiskRemoving Host-to-Virtual Disk Mapping Select Virtual Disk→ Change→ Ownership/Preferred Path 123 Select Disk Group→ Change→ Ownership/Preferred Path 124 Removing a Host-to-Virtual Disk Mapping Using Linux DmmpChanging the RAID Level of a Disk Group Select Disk Group→ Change→ RAID Level 125 Operating System Highest LUN Restricted Mappings126 127 128 129 Changing the RAID Level of a Disk Group 130 Storage Partitioning 131 Disk Group and Virtual Disk ExpansionSelect Disk Group→ Add Free Capacity Physical Disks 132 Using Free CapacityVirtual Disk Expansion Non-Exportable Components Using Unconfigured CapacityDisk Group Migration Export Disk Group 134 Import Disk GroupExporting a Disk Group Importing a Disk Group 135 Non-Importable Components 136 Changing Media Scan SettingsStorage Array Media Scan 137 Suspending the Media Scan 138 139 Configuration Premium Feature- Snapshot Virtual Disks 140 Scheduling a Snapshot Virtual DiskCommon Reasons for Scheduling a Snapshot Virtual Disk 141 Guidelines for Creating Snapshot Schedules 142 Creating a Snapshot Virtual Disk Using the Simple PathEnabling and Disabling Snapshot Schedules Scheduled Snapshot Icons 143 About the Simple Path 144 145 146 Creating a Snapshot Virtual Disk Using the Advanced PathAbout the Advanced Path 147 148 149 Creating the Snapshot Using the Advanced Path 150 Specify Virtual Disk Parameters window is displayed 151 Specifying Snapshot Virtual Disk Names 152 Snapshot Repository Capacity 153 154 Click Add Physical DisksAdd Physical Disks window closes 155 Disabling a Snapshot Virtual Disk 156 Preparing Host Servers to Re-create a Snapshot Virtual Disk 157 Re-creating Snapshot Virtual DisksSnapshot Rollback Select Virtual Disk→ Snapshot→ Re-create 158 Rules and Guidelines for Performing a Snapshot Rollback Starting a Snapshot Rollback Command Line OptionsProtecting Against a Failed Snapshot Rollback Previous Versions of the MD Storage Manager 160 Resuming a Snapshot RollbackRollback Confirm Rollback Snapshot Virtual Disk dialog is displayed 161 Canceling a Snapshot Rollback 162 163 Configuration Premium Feature- Virtual Disk Copy 164 Types of Virtual Disk CopiesOffline Copy 165 Online Copy 166 Creating a Virtual Disk Copy for an Mscs Shared DiskVirtual Disk Read/Write Permissions 167 Virtual Disk Copy Restrictions 168 Creating a Virtual Disk CopyBefore you Begin 169 Virtual Disk Copy and Modification OperationsCreate Copy Wizard Failed Virtual Disk Copy 170 Preferred RAID Controller Module OwnershipFailed RAID Controller Module Copy Manager 171 Copying the Virtual Disk 172 Storage Array Performance During Virtual Disk Copy 173 Setting Copy PriorityStopping a Virtual Disk Copy Select Change→ Copy Priority 174 Recopying a Virtual DiskPreparing Host Servers to Recopy a Virtual Disk 175 Re-Copying a Virtual Disk 176 Removing Copy PairsSelect Copy→ Re-Copy Select Copy→ Remove Copy Pairs 177 178 179 Configuration Device Mapper Multipath for Linux 180 Using DM Multipathing DevicesPrerequisite Steps 181 Device Mapper Configuration StepsScan for Newly Added Virtual Disks 182 183 Create a New fdisk Partition on a Multipath Device NodeAdd a New Partition to Device Mapper Blacklist Local Drive in Multi-path Driver Create a File System on a Device Mapper PartitionMount a Device Mapper Partition Ready for Use 185 Important Information About Special Partitions 186 Device Mapper Commands Descriptions 187 Limitations and Known Issues Question Answer Troubleshooting188 189 Downloading RAID Controller and Nvsram Packages 190 Downloading Both RAID Controller and Nvsram Firmware 191 Click Transfer 192 Downloading Only Nvsram Firmware 193 Select Tools→ Upgrade RAID Controller Module FirmwareUpgrade RAID Controller Module Firmware window is displayed 194 195 Downloading Physical Disk Firmware 196 197 AMW, select Advanced→ Maintenance→ Download→ EMM FirmwareDownloading MD1200 Series Expansion Module EMM Firmware Download Environmental EMM Firmware dialog is displayed 198 Media Errors and Unreadable SectorsSelf-Monitoring Analysis and Reporting Technology Smart 199 200 201 Management Installing Array ComponentsRecommended Tools 202 Installing the Front BezelFront Bezel Optional Removing the Front Bezel 203 Safety Models AMT, E03J, and E04JHard Drives Removing a Hard-Drive Blank 204 Installing a Hard-Drive BlankRemoving a Hard Drive 205 Removing and Installing a Hard Drive 206 Installing a Hard Drive 207 Removing a Hard Drive From a Hard-Drive Carrier 208 209 Installing a Hard Drive Into a Hard-Drive CarrierRAID Controller Module Removing a RAID Controller Module Blank 210 Installing a RAID Controller Module Blank 211 Removing a RAID Controller Module 212 Installing a RAID Controller ModuleOpening the RAID Controller Module 213 Closing the RAID Controller Module 214 RAID Controller Module Backup Battery UnitRemoving the RAID Controller Module Backup Battery Unit 215 Installing the RAID Controller Module Backup Battery Unit 216 Power Supply/Cooling Fan ModuleRemoving a Power Supply/Cooling Fan Module 217 Installing a Power Supply/Cooling Fan Module 218 Control PanelRemoving the Control Panel 219 220 Installing the Control Panel 221 BackplaneRemoving the Backplane 222 17. Removing and Installing the Backplane-PowerVault MD3220 16. Removing and Installing the Backplane-PowerVault MD3200 224 Installing the Backplane 225 Management Firmware InventoryViewing the Firmware Inventory 226 Management System Interfaces Microsoft ServicesVirtual Disk Service Volume Shadow-Copy Service 228 229 Troubleshooting Your Storage Array SoftwareStart-Up Routine Device Health Conditions Status Icon Description On the Setup tab, select Manage a Storage Array230 Additional Status Icons Description 231 232 Storage Array Support Data 233 Automatically Collect the Support Bundle DataEnter the Execution summary 234 Collecting the Physical Disk DataEvent Log 235 Recovery Guru 236 Storage Array ProfileSelect Storage Array→ View→ Profile 237 238 Viewing the Logical AssociationsViewing the Physical Associations 239 Finding Nodes 240 Using Go ToSelect Find all free capacity nodes Click Find Next 241 Recovering From an Unresponsive Storage Array Condition 242 243 244 Locating a Physical Disk 245 Locating an Expansion EnclosureSelect Physical Disk→ Blink→ Expansion Enclosure 246 Capturing the State Information 247 SMrepassist Utility 248 Recovering From an Unidentified Storage ArrayUnidentified Devices 249 250 251 Starting or Restarting the Host Context Agent Software 252 253 Troubleshooting Your ArrayTroubleshooting Loss of Communication Troubleshooting External Connections 254 Troubleshooting Power Supply/Cooling Fan Module 255 Troubleshooting Array Cooling ProblemsTroubleshooting Expansion Enclosure Management Modules 256 Troubleshooting RAID Controller Modules 257 258 Troubleshooting Hard Drives 259 Troubleshooting Array and Expansion Enclosure Connections 260 Troubleshooting a Wet Storage Array 261 Troubleshooting a Damaged ArrayConditions Critical Conditions ECC ErrorsPCI Errors Invalid Storage Array 263 Noncritical Conditions 264 Click All Support from Support menu Getting HelpContacting Dell Visit support.dell.com 266 267 Index 268 269 270 271 272