Jump To Close Expand all Collapse all Table of contents Storage Administration Guide 1. Overview Expand section "1. Overview" Collapse section "1. Overview" 1.1. New Features and Enhancements in Red Hat Enterprise Linux 7 I. File Systems Expand section "I. File Systems" Collapse section "I. File Systems" 2. File System Structure and Maintenance Expand section "2. File System Structure and Maintenance" Collapse section "2. File System Structure and Maintenance" 2.1. Overview of Filesystem Hierarchy Standard (FHS) Expand section "2.1. Overview of Filesystem Hierarchy Standard (FHS)" Collapse section "2.1. Overview of Filesystem Hierarchy Standard (FHS)" 2.1.1. FHS Organization Expand section "2.1.1. FHS Organization" Collapse section "2.1.1. FHS Organization" 2.1.1.1. Gathering File System Information 2.1.1.2. The /boot/ Directory 2.1.1.3. The /dev/ Directory 2.1.1.4. The /etc/ Directory 2.1.1.5. The /mnt/ Directory 2.1.1.6. The /opt/ Directory 2.1.1.7. The /proc/ Directory 2.1.1.8. The /srv/ Directory 2.1.1.9. The /sys/ Directory 2.1.1.10. The /usr/ Directory 2.1.1.11. The /var/ Directory 2.2. Special Red Hat Enterprise Linux File Locations 2.3. The /proc Virtual File System 2.4. Discard Unused Blocks 3. The XFS File System Expand section "3. The XFS File System" Collapse section "3. The XFS File System" 3.1. Creating an XFS File System 3.2. Mounting an XFS File System 3.3. XFS Quota Management 3.4. Increasing the Size of an XFS File System 3.5. Repairing an XFS File System 3.6. Suspending an XFS File System 3.7. Backing Up and Restoring XFS File Systems Expand section "3.7. Backing Up and Restoring XFS File Systems" Collapse section "3.7. Backing Up and Restoring XFS File Systems" 3.7.1. Features of XFS Backup and Restoration 3.7.2. Backing Up an XFS File System 3.7.3. Restoring an XFS File System from Backup 3.8. Configuring Error Behavior Expand section "3.8. Configuring Error Behavior" Collapse section "3.8. Configuring Error Behavior" 3.8.1. Configuration Files for Specific and Undefined Conditions 3.8.2. Setting File System Behavior for Specific and Undefined Conditions 3.8.3. Setting Unmount Behavior 3.9. Other XFS File System Utilities 3.10. Migrating from ext4 to XFS Expand section "3.10. Migrating from ext4 to XFS" Collapse section "3.10. Migrating from ext4 to XFS" 3.10.1. Differences Between Ext3/4 and XFS 4. The ext3 File System Expand section "4. The ext3 File System" Collapse section "4. The ext3 File System" 4.1. Creating an ext3 File System 4.2. Converting to an ext3 File System 4.3. Reverting to an Ext2 File System 5. The ext4 File System Expand section "5. The ext4 File System" Collapse section "5. The ext4 File System" 5.1. Creating an ext4 File System 5.2. Mounting an ext4 File System 5.3. Resizing an ext4 File System 5.4. Backing up ext2, ext3, or ext4 File Systems 5.5. Restoring ext2, ext3, or ext4 File Systems 5.6. Other ext4 File System Utilities 6. Btrfs (Technology Preview) Expand section "6. Btrfs (Technology Preview)" Collapse section "6. Btrfs (Technology Preview)" 6.1. Creating a btrfs File System 6.2. Mounting a btrfs file system 6.3. Resizing a btrfs File System 6.4. Integrated Volume Management of Multiple Devices Expand section "6.4. Integrated Volume Management of Multiple Devices" Collapse section "6.4. Integrated Volume Management of Multiple Devices" 6.4.1. Creating a File System with Multiple Devices 6.4.2. Scanning for btrfs Devices 6.4.3. Adding New Devices to a btrfs File System 6.4.4. Converting a btrfs File System 6.4.5. Removing btrfs Devices 6.4.6. Replacing Failed Devices on a btrfs File System 6.4.7. Registering a btrfs File System in /etc/fstab 6.5. SSD Optimization 6.6. btrfs References 7. Global File System 2 8. Network File System (NFS) Expand section "8. Network File System (NFS)" Collapse section "8. Network File System (NFS)" 8.1. Introduction to NFS Expand section "8.1. Introduction to NFS" Collapse section "8.1. Introduction to NFS" 8.1.1. Required Services 8.2. Configuring NFS Client Expand section "8.2. Configuring NFS Client" Collapse section "8.2. Configuring NFS Client" 8.2.1. Mounting NFS File Systems Using /etc/fstab 8.3. autofs Expand section "8.3. autofs" Collapse section "8.3. autofs" 8.3.1. Improvements in autofs Version 5 over Version 4 8.3.2. Configuring autofs 8.3.3. Overriding or Augmenting Site Configuration Files 8.3.4. Using LDAP to Store Automounter Maps 8.4. Common NFS Mount Options 8.5. Starting and Stopping the NFS Server 8.6. Configuring the NFS Server Expand section "8.6. Configuring the NFS Server" Collapse section "8.6. Configuring the NFS Server" 8.6.1. The /etc/exports Configuration File 8.6.2. The exportfs Command Expand section "8.6.2. The exportfs Command" Collapse section "8.6.2. The exportfs Command" 8.6.2.1. Using exportfs with NFSv4 8.6.3. Running NFS Behind a Firewall Expand section "8.6.3. Running NFS Behind a Firewall" Collapse section "8.6.3. Running NFS Behind a Firewall" 8.6.3.1. Discovering NFS exports 8.6.4. Accessing RPC Quota through a Firewall 8.6.5. Hostname Formats 8.6.6. Enabling NFS over RDMA (NFSoRDMA) 8.6.7. Configuring an NFSv4-only Server 8.7. Securing NFS Expand section "8.7. Securing NFS" Collapse section "8.7. Securing NFS" 8.7.1. NFS Security with AUTH_SYS and Export Controls 8.7.2. NFS Security with AUTH_GSS Expand section "8.7.2. NFS Security with AUTH_GSS" Collapse section "8.7.2. NFS Security with AUTH_GSS" 8.7.2.1. NFS Security with NFSv4 8.7.3. File Permissions 8.8. NFS and rpcbind Expand section "8.8. NFS and rpcbind" Collapse section "8.8. NFS and rpcbind" 8.8.1. Troubleshooting NFS and rpcbind 8.9. pNFS 8.10. Enabling pNFS SCSI Layouts in NFS Expand section "8.10. Enabling pNFS SCSI Layouts in NFS" Collapse section "8.10. Enabling pNFS SCSI Layouts in NFS" 8.10.1. pNFS SCSI Layouts 8.10.2. Checking for a SCSI Device Compatible with pNFS 8.10.3. Setting up pNFS SCSI on the Server 8.10.4. Setting up pNFS SCSI on the Client 8.10.5. Releasing the pNFS SCSI Reservation on the Server 8.10.6. Monitoring pNFS SCSI Layouts Functionality Expand section "8.10.6. Monitoring pNFS SCSI Layouts Functionality" Collapse section "8.10.6. Monitoring pNFS SCSI Layouts Functionality" 8.10.6.1. Checking pNFS SCSI Operations from the Server Using nfsstat 8.10.6.2. Checking pNFS SCSI Operations from the Client Using mountstats 8.11. NFS References 9. Server Message Block (SMB) Expand section "9. Server Message Block (SMB)" Collapse section "9. Server Message Block (SMB)" 9.1. Providing SMB Shares 9.2. Mounting an SMB Share Expand section "9.2. Mounting an SMB Share" Collapse section "9.2. Mounting an SMB Share" 9.2.1. Supported SMB Protocol Versions Expand section "9.2.1. Supported SMB Protocol Versions" Collapse section "9.2.1. Supported SMB Protocol Versions" 9.2.1.1. UNIX Extensions Support 9.2.2. Manually Mounting an SMB Share 9.2.3. Mounting an SMB Share Automatically When the System Boots 9.2.4. Authenticating To an SMB Share Using a Credentials File 9.2.5. Performing a Multi-user SMB Mount 9.2.6. Frequently Used Mount Options 10. FS-Cache Expand section "10. FS-Cache" Collapse section "10. FS-Cache" 10.1. Performance Guarantee 10.2. Setting up a Cache 10.3. Using the Cache with NFS Expand section "10.3. Using the Cache with NFS" Collapse section "10.3. Using the Cache with NFS" 10.3.1. Cache Sharing 10.3.2. Cache Limitations with NFS 10.4. Setting Cache Cull Limits 10.5. Statistical Information 10.6. FS-Cache References II. Storage Administration Expand section "II. Storage Administration" Collapse section "II. Storage Administration" 11. Storage Considerations During Installation Expand section "11. Storage Considerations During Installation" Collapse section "11. Storage Considerations During Installation" 11.1. Special Considerations 12. File System Check Expand section "12. File System Check" Collapse section "12. File System Check" 12.1. Best Practices for fsck 12.2. File System-Specific Information for fsck Expand section "12.2. File System-Specific Information for fsck" Collapse section "12.2. File System-Specific Information for fsck" 12.2.1. ext2, ext3, and ext4 12.2.2. XFS 12.2.3. Btrfs 13. Partitions Expand section "13. Partitions" Collapse section "13. Partitions" 13.1. Viewing the Partition Table 13.2. Creating a Partition Expand section "13.2. Creating a Partition" Collapse section "13.2. Creating a Partition" 13.2.1. Formatting and Labeling the Partition 13.2.2. Add the Partition to /etc/fstab 13.3. Removing a Partition 13.4. Setting a Partition Type 13.5. Resizing a Partition with fdisk 14. Creating and Maintaining Snapshots with Snapper Expand section "14. Creating and Maintaining Snapshots with Snapper" Collapse section "14. Creating and Maintaining Snapshots with Snapper" 14.1. Creating Initial Snapper Configuration 14.2. Creating a Snapper Snapshot Expand section "14.2. Creating a Snapper Snapshot" Collapse section "14.2. Creating a Snapper Snapshot" 14.2.1. Creating a Pre and Post Snapshot Pair Expand section "14.2.1. Creating a Pre and Post Snapshot Pair" Collapse section "14.2.1. Creating a Pre and Post Snapshot Pair" 14.2.1.1. Creating a Pre Snapshot with Snapper 14.2.1.2. Creating a Post Snapshot with Snapper 14.2.1.3. Wrapping a Command in Pre and Post Snapshots 14.2.2. Creating a Single Snapper Snapshot 14.2.3. Configuring Snapper to Take Automated Snapshots 14.3. Tracking Changes Between Snapper Snapshots Expand section "14.3. Tracking Changes Between Snapper Snapshots" Collapse section "14.3. Tracking Changes Between Snapper Snapshots" 14.3.1. Comparing Changes with the status Command 14.3.2. Comparing Changes with the diff Command 14.3.3. Comparing Changes with the xadiff Command 14.4. Reversing Changes in Between Snapshots 14.5. Deleting a Snapper Snapshot 15. Swap Space Expand section "15. Swap Space" Collapse section "15. Swap Space" 15.1. Adding Swap Space Expand section "15.1. Adding Swap Space" Collapse section "15.1. Adding Swap Space" 15.1.1. Extending Swap on an LVM2 Logical Volume 15.1.2. Creating an LVM2 Logical Volume for Swap 15.1.3. Creating a Swap File 15.2. Removing Swap Space Expand section "15.2. Removing Swap Space" Collapse section "15.2. Removing Swap Space" 15.2.1. Reducing Swap on an LVM2 Logical Volume 15.2.2. Removing an LVM2 Logical Volume for Swap 15.2.3. Removing a Swap File 15.3. Moving Swap Space 16. System Storage Manager (SSM) Expand section "16. System Storage Manager (SSM)" Collapse section "16. System Storage Manager (SSM)" 16.1. SSM Back Ends Expand section "16.1. SSM Back Ends" Collapse section "16.1. SSM Back Ends" 16.1.1. Btrfs Back End Expand section "16.1.1. Btrfs Back End" Collapse section "16.1.1. Btrfs Back End" 16.1.1.1. Btrfs Pool 16.1.1.2. Btrfs Volume 16.1.1.3. Btrfs Snapshot 16.1.1.4. Btrfs Device 16.1.2. LVM Back End Expand section "16.1.2. LVM Back End" Collapse section "16.1.2. LVM Back End" 16.1.2.1. LVM Pool 16.1.2.2. LVM Volume 16.1.2.3. LVM Snapshot 16.1.2.4. LVM Device 16.1.3. Crypt Back End Expand section "16.1.3. Crypt Back End" Collapse section "16.1.3. Crypt Back End" 16.1.3.1. Crypt Volume 16.1.3.2. Crypt Snapshot 16.1.4. Multiple Devices (MD) Back End 16.2. Common SSM Tasks Expand section "16.2. Common SSM Tasks" Collapse section "16.2. Common SSM Tasks" 16.2.1. Installing SSM 16.2.2. Displaying Information about All Detected Devices 16.2.3. Creating a New Pool, Logical Volume, and File System 16.2.4. Checking a File System's Consistency 16.2.5. Increasing a Volume's Size 16.2.6. Snapshot 16.2.7. Removing an Item 16.3. SSM Resources 17. Disk Quotas Expand section "17. Disk Quotas" Collapse section "17. Disk Quotas" 17.1. Configuring Disk Quotas Expand section "17.1. Configuring Disk Quotas" Collapse section "17.1. Configuring Disk Quotas" 17.1.1. Enabling Quotas 17.1.2. Remounting the File Systems 17.1.3. Creating the Quota Database Files 17.1.4. Assigning Quotas per User 17.1.5. Assigning Quotas per Group 17.1.6. Setting the Grace Period for Soft Limits 17.2. Managing Disk Quotas Expand section "17.2. Managing Disk Quotas" Collapse section "17.2. Managing Disk Quotas" 17.2.1. Enabling and Disabling 17.2.2. Reporting on Disk Quotas 17.2.3. Keeping Quotas Accurate 17.3. Disk Quota References 18. Redundant Array of Independent Disks (RAID) Expand section "18. Redundant Array of Independent Disks (RAID)" Collapse section "18. Redundant Array of Independent Disks (RAID)" 18.1. RAID Types 18.2. RAID Levels and Linear Support 18.3. Linux RAID Subsystems 18.4. RAID Support in the Anaconda Installer 18.5. Converting Root Disk to RAID1 after Installation 18.6. Configuring RAID Sets 18.7. Creating Advanced RAID Devices 19. Using the mount Command Expand section "19. Using the mount Command" Collapse section "19. Using the mount Command" 19.1. Listing Currently Mounted File Systems Expand section "19.1. Listing Currently Mounted File Systems" Collapse section "19.1. Listing Currently Mounted File Systems" 19.1.1. Specifying the File System Type 19.2. Mounting a File System Expand section "19.2. Mounting a File System" Collapse section "19.2. Mounting a File System" 19.2.1. Specifying the File System Type 19.2.2. Specifying the Mount Options 19.2.3. Sharing Mounts 19.2.4. Moving a Mount Point 19.2.5. Setting Read-only Permissions for root Expand section "19.2.5. Setting Read-only Permissions for root" Collapse section "19.2.5. Setting Read-only Permissions for root" 19.2.5.1. Configuring root to Mount with Read-only Permissions on Boot 19.2.5.2. Remounting root Instantly 19.2.5.3. Files and Directories That Retain Write Permissions 19.3. Unmounting a File System 19.4. mount Command References 20. The volume_key Function Expand section "20. The volume_key Function" Collapse section "20. The volume_key Function" 20.1. volume_key Commands 20.2. Using volume_key as an Individual User 20.3. Using volume_key in a Larger Organization Expand section "20.3. Using volume_key in a Larger Organization" Collapse section "20.3. Using volume_key in a Larger Organization" 20.3.1. Preparation for Saving Encryption Keys 20.3.2. Saving Encryption Keys 20.3.3. Restoring Access to a Volume 20.3.4. Setting up Emergency Passphrases 20.4. volume_key References 21. Solid-State Disk Deployment Guidelines 22. Write Barriers Expand section "22. Write Barriers" Collapse section "22. Write Barriers" 22.1. Importance of Write Barriers 22.2. Enabling and Disabling Write Barriers 22.3. Write Barrier Considerations 23. Storage I/O Alignment and Size Expand section "23. Storage I/O Alignment and Size" Collapse section "23. Storage I/O Alignment and Size" 23.1. Parameters for Storage Access 23.2. Userspace Access 23.3. I/O Standards 23.4. Stacking I/O Parameters 23.5. Logical Volume Manager 23.6. Partition and File System Tools 24. Setting up a Remote Diskless System Expand section "24. Setting up a Remote Diskless System" Collapse section "24. Setting up a Remote Diskless System" 24.1. Configuring a tftp Service for Diskless Clients 24.2. Configuring DHCP for Diskless Clients 24.3. Configuring an Exported File System for Diskless Clients 25. Online Storage Management Expand section "25. Online Storage Management" Collapse section "25. Online Storage Management" 25.1. Target Setup Expand section "25.1. Target Setup" Collapse section "25.1. Target Setup" 25.1.1. Installing and Running targetcli 25.1.2. Creating a Backstore 25.1.3. Creating an iSCSI Target 25.1.4. Configuring an iSCSI Portal 25.1.5. Configuring LUNs 25.1.6. Configuring ACLs 25.1.7. Configuring Fibre Channel over Ethernet (FCoE) Target 25.1.8. Removing Objects with targetcli 25.1.9. targetcli References 25.2. Creating an iSCSI Initiator 25.3. Setting up the Challenge-Handshake Authentication Protocol 25.4. Fibre Channel Expand section "25.4. Fibre Channel" Collapse section "25.4. Fibre Channel" 25.4.1. Fibre Channel API 25.4.2. Native Fibre Channel Drivers and Capabilities 25.5. Configuring a Fibre Channel over Ethernet Interface 25.6. Configuring an FCoE Interface to Automatically Mount at Boot 25.7. iSCSI Expand section "25.7. iSCSI" Collapse section "25.7. iSCSI" 25.7.1. iSCSI API 25.8. Persistent Naming Expand section "25.8. Persistent Naming" Collapse section "25.8. Persistent Naming" 25.8.1. Major and Minor Numbers of Storage Devices 25.8.2. World Wide Identifier (WWID) 25.8.3. Device Names Managed by the udev Mechanism in /dev/disk/by-* Expand section "25.8.3. Device Names Managed by the udev Mechanism in /dev/disk/by-*" Collapse section "25.8.3. Device Names Managed by the udev Mechanism in /dev/disk/by-*" 25.8.3.1. Limitations of the udev Device Naming Convention 25.8.3.2. Modifying Persistent Naming Attributes 25.9. Removing a Storage Device 25.10. Removing a Path to a Storage Device 25.11. Adding a Storage Device or Path 25.12. Scanning Storage Interconnects 25.13. iSCSI Discovery Configuration 25.14. Configuring iSCSI Offload and Interface Binding Expand section "25.14. Configuring iSCSI Offload and Interface Binding" Collapse section "25.14. Configuring iSCSI Offload and Interface Binding" 25.14.1. Viewing Available iface Configurations 25.14.2. Configuring an iface for Software iSCSI 25.14.3. Configuring an iface for iSCSI Offload 25.14.4. Binding/Unbinding an iface to a Portal 25.15. Scanning iSCSI Interconnects 25.16. Logging in to an iSCSI Target 25.17. Resizing an Online Logical Unit Expand section "25.17. Resizing an Online Logical Unit" Collapse section "25.17. Resizing an Online Logical Unit" 25.17.1. Resizing Fibre Channel Logical Units 25.17.2. Resizing an iSCSI Logical Unit 25.17.3. Updating the Size of Your Multipath Device 25.17.4. Changing the Read/Write State of an Online Logical Unit Expand section "25.17.4. Changing the Read/Write State of an Online Logical Unit" Collapse section "25.17.4. Changing the Read/Write State of an Online Logical Unit" 25.17.4.1. Rescanning Logical Units 25.17.4.2. Updating the R/W State of a Multipath Device 25.17.4.3. Documentation 25.18. Adding/Removing a Logical Unit Through rescan-scsi-bus.sh 25.19. Modifying Link Loss Behavior Expand section "25.19. Modifying Link Loss Behavior" Collapse section "25.19. Modifying Link Loss Behavior" 25.19.1. Fibre Channel 25.19.2. iSCSI Settings with dm-multipath Expand section "25.19.2. iSCSI Settings with dm-multipath" Collapse section "25.19.2. iSCSI Settings with dm-multipath" 25.19.2.1. NOP-Out Interval/Timeout 25.19.2.2. replacement_timeout 25.19.3. iSCSI Root 25.20. Controlling the SCSI Command Timer and Device Status 25.21. Troubleshooting Online Storage Configuration 25.22. Configuring Maximum Time for Error Recovery with eh_deadline 26. Device Mapper Multipathing (DM Multipath) and Storage for Virtual Machines Expand section "26. Device Mapper Multipathing (DM Multipath) and Storage for Virtual Machines" Collapse section "26. Device Mapper Multipathing (DM Multipath) and Storage for Virtual Machines" 26.1. Storage for Virtual Machines 26.2. DM Multipath 27. External Array Management (libStorageMgmt) Expand section "27. External Array Management (libStorageMgmt)" Collapse section "27. External Array Management (libStorageMgmt)" 27.1. Introduction to libStorageMgmt 27.2. libStorageMgmt Terminology 27.3. Installing libStorageMgmt 27.4. Using libStorageMgmt 28. Persistent Memory: NVDIMMs Expand section "28. Persistent Memory: NVDIMMs" Collapse section "28. Persistent Memory: NVDIMMs" 28.1. Configuring Persistent Memory with ndctl 28.2. Configuring Persistent Memory for Use as a Block Device (Legacy Mode) 28.3. Configuring Persistent Memory for File System Direct Access 28.4. Configuring Persistent Memory for use in Device DAX mode 28.5. Troubleshooting NVDIMM Expand section "28.5. Troubleshooting NVDIMM" Collapse section "28.5. Troubleshooting NVDIMM" 28.5.1. Monitoring NVDIMM Health Using S.M.A.R.T. 28.5.2. Detecting and Replacing a Broken NVDIMM 29. Overview of NVMe over fabric devices Expand section "29. Overview of NVMe over fabric devices" Collapse section "29. Overview of NVMe over fabric devices" 29.1. NVMe over fabrics using RDMA Expand section "29.1. NVMe over fabrics using RDMA" Collapse section "29.1. NVMe over fabrics using RDMA" 29.1.1. Configuring an NVMe over RDMA client 29.2. NVMe over fabrics using FC Expand section "29.2. NVMe over fabrics using FC" Collapse section "29.2. NVMe over fabrics using FC" 29.2.1. Configuring the NVMe initiator for Broadcom adapters 29.2.2. Configuring the NVMe initiator for QLogic adapters III. Data Deduplication and Compression with VDO Expand section "III. Data Deduplication and Compression with VDO" Collapse section "III. Data Deduplication and Compression with VDO" 30. VDO Integration Expand section "30. VDO Integration" Collapse section "30. VDO Integration" 30.1. Theoretical Overview of VDO Expand section "30.1. Theoretical Overview of VDO" Collapse section "30.1. Theoretical Overview of VDO" 30.1.1. The UDS Kernel Module (uds) 30.1.2. The VDO Kernel Module (kvdo) 30.1.3. VDO Volume 30.1.4. Command Line Tools 30.2. System Requirements Expand section "30.2. System Requirements" Collapse section "30.2. System Requirements" 30.2.1. UDS Index Memory Requirements 30.2.2. VDO Storage Space Requirements 30.2.3. Examples of VDO System Requirements by Physical Volume Size 30.3. Getting Started with VDO Expand section "30.3. Getting Started with VDO" Collapse section "30.3. Getting Started with VDO" 30.3.1. Introduction 30.3.2. Installing VDO 30.3.3. Creating a VDO Volume 30.3.4. Monitoring VDO 30.3.5. Deployment Examples 30.4. Administering VDO Expand section "30.4. Administering VDO" Collapse section "30.4. Administering VDO" 30.4.1. Starting or Stopping VDO 30.4.2. Selecting VDO Write Modes 30.4.3. Removing VDO Volumes Expand section "30.4.3. Removing VDO Volumes" Collapse section "30.4.3. Removing VDO Volumes" 30.4.3.1. Removing an Unsuccessfully Created Volume 30.4.4. Configuring the UDS Index 30.4.5. Recovering a VDO Volume After an Unclean Shutdown Expand section "30.4.5. Recovering a VDO Volume After an Unclean Shutdown" Collapse section "30.4.5. Recovering a VDO Volume After an Unclean Shutdown" 30.4.5.1. Online Recovery 30.4.5.2. Forcing a Rebuild 30.4.6. Automatically Starting VDO Volumes at System Boot 30.4.7. Disabling and Re-enabling Deduplication 30.4.8. Using Compression Expand section "30.4.8. Using Compression" Collapse section "30.4.8. Using Compression" 30.4.8.1. Introduction 30.4.8.2. Enabling and Disabling Compression 30.4.9. Managing Free Space 30.4.10. Increasing Logical Volume Size 30.4.11. Increasing Physical Volume Size 30.4.12. Automating VDO with Ansible 30.5. Deployment Scenarios Expand section "30.5. Deployment Scenarios" Collapse section "30.5. Deployment Scenarios" 30.5.1. iSCSI Target 30.5.2. File Systems 30.5.3. LVM 30.5.4. Encryption 30.6. Tuning VDO Expand section "30.6. Tuning VDO" Collapse section "30.6. Tuning VDO" 30.6.1. Introduction to VDO Tuning 30.6.2. Background on VDO Architecture 30.6.3. Values to tune Expand section "30.6.3. Values to tune" Collapse section "30.6.3. Values to tune" 30.6.3.1. CPU/memory Expand section "30.6.3.1. CPU/memory" Collapse section "30.6.3.1. CPU/memory" 30.6.3.1.1. Logical, physical, cpu, ack thread counts 30.6.3.1.2. CPU Affinity and NUMA 30.6.3.1.3. Frequency throttling 30.6.3.2. Caching Expand section "30.6.3.2. Caching" Collapse section "30.6.3.2. Caching" 30.6.3.2.1. Block Map Cache 30.6.3.2.2. Read Cache 30.6.3.3. Storage System I/O Expand section "30.6.3.3. Storage System I/O" Collapse section "30.6.3.3. Storage System I/O" 30.6.3.3.1. Bio Threads 30.6.3.3.2. IRQ Handling 30.6.3.4. Maximum Discard Sectors 30.6.4. Identifying Bottlenecks 30.7. VDO Commands Expand section "30.7. VDO Commands" Collapse section "30.7. VDO Commands" 30.7.1. vdo 30.7.2. vdostats 30.8. Statistics Files in /sys 31. VDO Evaluation Expand section "31. VDO Evaluation" Collapse section "31. VDO Evaluation" 31.1. Introduction Expand section "31.1. Introduction" Collapse section "31.1. Introduction" 31.1.1. Expectations and Deliverables 31.2. Test Environment Preparations Expand section "31.2. Test Environment Preparations" Collapse section "31.2. Test Environment Preparations" 31.2.1. System Configuration 31.2.2. VDO Configuration 31.2.3. Workloads 31.2.4. Supported System Configurations 31.2.5. Pre-Test System Preparations 31.2.6. VDO Internal Structures 31.2.7. VDO Optimizations 31.2.8. Special Considerations for Testing Read Performance 31.2.9. Cross Talk 31.3. Data Efficiency Testing Procedures Expand section "31.3. Data Efficiency Testing Procedures" Collapse section "31.3. Data Efficiency Testing Procedures" 31.3.1. Configuring a VDO Test Volume 31.3.2. Testing VDO Efficiency 31.4. Performance Testing Procedures Expand section "31.4. Performance Testing Procedures" Collapse section "31.4. Performance Testing Procedures" 31.4.1. Phase 1: Effects of I/O Depth, Fixed 4 KB Blocks 31.4.2. Phase 2: Effects of I/O Request Size 31.4.3. Phase 3: Effects of Mixing Read & Write I/Os 31.4.4. Phase 4: Application Environments 31.5. Issue Reporting 31.6. Conclusion A. Red Hat Customer Portal Labs Relevant to Storage Administration B. Revision History Index Legal Notice Settings Close Language: 한국어 日本語 简体中文 English Français Language: 한국어 日本語 简体中文 English Français Format: Multi-page Single-page PDF Format: Multi-page Single-page PDF Language and Page Formatting Options Language: 한국어 日本語 简体中文 English Français Language: 한국어 日本語 简体中文 English Français Format: Multi-page Single-page PDF Format: Multi-page Single-page PDF Red Hat Training A Red Hat training course is available for Red Hat Enterprise Linux 17.3. Disk Quota References For more information on disk quotas, refer to the man pages of the following commands: quotacheck edquota repquota quota quotaon quotaoff Previous Next