Veritas Access Administrator's Guide
- Section I. Introducing Veritas Access
- Section II. Configuring Veritas Access
- Adding users or roles
- Configuring the network
- Configuring authentication services
- Section III. Managing Veritas Access storage
- Configuring storage
- Configuring data integrity with I/O fencing
- Configuring ISCSI
- Veritas Access as an iSCSI target
- Configuring storage
- Section IV. Managing Veritas Access file access services
- Configuring the NFS server
- Setting up Kerberos authentication for NFS clients
- Using Veritas Access as a CIFS server
- About Active Directory (AD)
- About configuring CIFS for Active Directory (AD) domain mode
- About setting trusted domains
- About managing home directories
- About CIFS clustering modes
- About migrating CIFS shares and home directories
- About managing local users and groups
- Configuring an FTP server
- Using Veritas Access as an Object Store server
- Configuring the NFS server
- Section V. Monitoring and troubleshooting
- Section VI. Provisioning and managing Veritas Access file systems
- Creating and maintaining file systems
- Considerations for creating a file system
- Modifying a file system
- Managing a file system
- Creating and maintaining file systems
- Section VII. Configuring cloud storage
- Section VIII. Provisioning and managing Veritas Access shares
- Creating shares for applications
- Creating and maintaining NFS shares
- Creating and maintaining CIFS shares
- Using Veritas Access with OpenStack
- Integrating Veritas Access with Data Insight
- Section IX. Managing Veritas Access storage services
- Compressing files
- About compressing files
- Compression tasks
- Configuring SmartTier
- Configuring SmartIO
- Configuring episodic replication
- Episodic replication job failover and failback
- Configuring continuous replication
- How Veritas Access continuous replication works
- Continuous replication failover and failback
- Using snapshots
- Using instant rollbacks
- Compressing files
- Section X. Reference
About the file compression attributes
When you compress a file with the Storage> compress command, compress attaches the following information to the inode:
Compression algorithm
Compression strength, which is a number from 1 to 9
Compression block size
This information is referred to as the file compression attributes. The purpose of the attributes are to collect the parameters used to create the compressed file. The information can then be read by a backup program.
The file compression attributes guarantee that a particular compressed file can only use one type and strength of compression. Recompressing a file using different attributes fails. To change the file compression attributes, you must explicitly uncompress first, and then recompress with the new options, even in the case where all extents are already uncompressed.
The file compression attributes do not indicate if all extents are compressed. Some extents might be incompressible, and other extents or even all extents might be uncompressed due to writes, but the file compression attributes remain. Only an explicit file uncompression can remove the attributes.