Veritas Access Appliance Administrator's Guide
- Section I. Introducing Access Appliance
- Section II. Configuring Access Appliance
- Managing users
- Configuring the network
- Configuring authentication services
- Configuring user authentication using digital certificates or smart cards
- Section III. Managing Access Appliance storage
- Configuring storage
- Managing disks
- Access Appliance as an iSCSI target
- Configuring storage
- Section IV. Managing Access Appliance file access services
- Configuring the NFS server
- Setting up Kerberos authentication for NFS clients
- Using Access Appliance as a CIFS server
- 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
- Using Access Appliance as an Object Store server
- Configuring the NFS server
- Section V. Managing Access Appliance security
- Section VI. Monitoring and troubleshooting
- Configuring event notifications and audit logs
- About alert management
- Appliance log files
- Configuring event notifications and audit logs
- Section VII. Provisioning and managing Access Appliance file systems
- Creating and maintaining file systems
- Considerations for creating a file system
- About managing application I/O workloads using maximum IOPS settings
- Modifying a file system
- Managing a file system
- Creating and maintaining file systems
- Section VIII. Provisioning and managing Access Appliance shares
- Creating shares for applications
- Creating and maintaining NFS shares
- About the NFS shares
- Creating and maintaining CIFS shares
- About the CIFS shares
- About managing CIFS shares for Enterprise Vault
- Integrating Access Appliance with Data Insight
- Section IX. Managing Access Appliance storage services
- Configuring episodic replication
- Episodic replication job failover and failback
- Configuring continuous replication
- How Access Appliance continuous replication works
- Continuous replication failover and failback
- Using snapshots
- Using instant rollbacks
- Configuring episodic replication
- Section X. Reference
About instant rollbacks
Instant rollbacks are volume-level snapshots. All rollback commands take a file system name as an argument and perform operations on the underlying volume of that file system.
Note:
If you plan to add a tier to the file system, add the tier first and then create the rollback. If you add the tier after a rollback exists, the rollback hierarchy would have inconsistencies because the rollback is not aware of the tier.
Both space-optimized and full-sized rollbacks are supported by Access Appliance. Space-optimized rollbacks use a storage cache, and do not need a complete copy of the original volume's storage space. However, space-optimized rollbacks are not suitable for write-intensive volumes, because the copy-on-write mechanism may degrade the performance of the volume. Full-sized rollbacks use more storage, but that has little impact on write performance after synchronization is completed.
Both space-optimized rollbacks and full-sized rollbacks can be used instantly after operations such as create, restore, or refresh.
Note:
When instant rollbacks exist for a volume, you cannot disable the FastResync option for a file system.
When creating instant rollbacks for volumes bigger than 1T, there may be error messages such as the following:
ACCESS instant_snapshot ERROR V-288-1487 Volume prepare for full-fs1-1 failed.
An error message may occur because the default amount of memory allocated for a Data Change Object (DCO) may not be large enough for such big volumes. You can use the vxtune command to change the value. The default value is 6M, which is the memory required for a 1T volume.
To change it to 15M, use the following command:
vxtune volpagemod_max_memsz `expr 15 \* 1024 \* 1024`