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Contents Contents i List of Tables vi 1 ZFS File System (Introduction)1 1.1 What’s New in ZFS? . .1 Using Cache Devices in Your ZFS Storage Pool . .3 Enhancements to the zfs send Command . .3 ZFS Quotas and Reservations for File System Data Only . .4 ZFS File System Properties for the Solaris CIFS Service . .4 ZFS Storage Pool Properties . .5 ZFS and File System Mirror Mounts . .6 ZFS Command History Enhancements (zpool history)..................6 Upgrading ZFS File Systems (zfs upgrade)........................7 ZFS Delegated Administration . .8 Setting Up Separate ZFS Logging Devices . .8 Creating Intermediate ZFS Datasets . .9 ZFS Hotplugging Enhancements . 10 Recursively Renaming ZFS Snapshots (zfs rename -r).................. 10 GZIP Compression is Available for ZFS . 11 Storing Multiple Copies of ZFS User Data . 11 Improved zpool status Output . 12 ZFS and Solaris iSCSI Improvements . 12 Sharing ZFS File System Enhancements . 12 ZFS Command History (zpool history).......................... 13 ZFS Property Improvements . 14 ZFS xattr Property . 14 ZFS canmount Property . 14 ZFS User Properties . 14 Setting Properties When Creating ZFS File Systems . 14 Displaying All ZFS File System Information . 15 New zfs receive -F Option . 15 Recursive ZFS Snapshots . 15 Double Parity RAID-Z (raidz2)............................. 15 Hot Spares for ZFS Storage Pool Devices . 15 Replacing a ZFS File System With a ZFS Clone (zfs promote).............. 16 Upgrading ZFS Storage Pools (zpool upgrade)...................... 16 Using ZFS to Clone Non-Global Zones and Other Enhancements . 16 i CONTENTS ZFS Backup and Restore Commands are Renamed . 17 Recovering Destroyed Storage Pools . 17 ZFS is Integrated With Fault Manager . 17 New zpool clear Command . 17 Compact NFSv4 ACL Format . 17 File System Monitoring Tool (fsstat)............................ 18 ZFS Web-Based Management . 18 1.2 What Is ZFS? . 19 ZFS Pooled Storage . 19 Transactional Semantics . 19 Checksums and Self-Healing Data . 20 Unparalleled Scalability . 20 ZFS Snapshots . 20 Simplified Administration . 20 1.3 ZFS Terminology . 21 1.4 ZFS Component Naming Requirements . 22 2 Getting Started With ZFS 23 2.1 ZFS Hardware and Software Requirements and Recommendations . 23 2.2 Creating a Basic ZFS File System . 23 2.3 Creating a ZFS Storage Pool . 24 2.4 Creating a ZFS File System Hierarchy . 26 3 ZFS and Traditional File System Differences 29 3.1 ZFS File System Granularity . 29 3.2 ZFS Space Accounting . 30 Out of Space Behavior . 30 3.3 Mounting ZFS File Systems . 30 3.4 Traditional Volume Management . 31 3.5 The NFSv4 ACL Model . 31 4 Managing ZFS Storage Pools 33 4.1 Components of a ZFS Storage Pool . 33 Using Disks in a ZFS Storage Pool . 33 Using Files in a ZFS Storage Pool . 35 Identifying Virtual Devices in a Storage Pool . 35 4.2 Replication Features of a ZFS Storage Pool . 35 Mirrored Storage Pool Configuration . 36 RAID-Z Storage Pool Configuration . 36 Self-Healing Data in a Redundant Configuration . 37 Dynamic Striping in a Storage Pool . 37 4.3 Creating and Destroying ZFS Storage Pools . 37 Creating a ZFS Storage Pool . 37 Creating a Basic Storage Pool . 38 Creating a Mirrored Storage Pool . 38 Creating RAID-Z Storage Pools . 38 Creating a ZFS Storage Pool with Log Devices . 39 Creating a ZFS Storage Pool with Cache Devices . 40 Handling ZFS Storage Pool Creation Errors . 41 ii Contents Detecting in Use Devices . 41 Mismatched Replication Levels . 42 Doing a Dry Run of Storage Pool Creation . 42 Default Mount Point for Storage Pools . 43 Destroying ZFS Storage Pools . 43 Destroying a Pool With Faulted Devices . 43 4.4 Managing Devices in ZFS Storage Pools . 44 Adding Devices to a Storage Pool . 44 Attaching and Detaching Devices in a Storage Pool . 47 Onlining and Offlining Devices in a Storage Pool . 48 Taking a Device Offline . 49 Bringing a Device Online . 49 Clearing Storage Pool Devices . 50 Replacing Devices in a Storage Pool . 50 Designating Hot Spares in Your Storage Pool . 51 Activating and Deactivating Hot Spares in Your Storage Pool . 52 4.5 Managing ZFS Storage Pool Properties . 54 4.6 Querying ZFS Storage Pool Status . 56 Displaying Basic ZFS Storage Pool Information . 56 Listing Information About All Storage Pools . 56 Listing Specific Storage Pool Statistics . 57 Scripting ZFS Storage Pool Output . 58 Viewing ZFS Storage Pool I/O Statistics . 58 Listing Pool-Wide Statistics . 58 Listing Virtual Device Statistics . ..