Home > Storage > PowerVault > Guides > Dell PowerVault ME4 Series and Linux > Using snapshots to roll back or reset a volume
The rollback feature replaces the data of a source volume/snapshot with the data of another snapshot that is created from it. This is useful to quickly restore a point-in-time copy of data on the original host without reconfiguring the applications on the host.
The reset feature replaces the data of a snapshot with the current data of the source volume. A common use case would be to resynchronize the test data with the most up-to-date data from the production source volume.
Because the rollback and reset features preserve the mapping and identity of the volume, there is no reconfiguration needed on the host. Although I/O access to the volume is restricted while the rollback or reset is in progress, it is highly recommended to dismount the volume on the host and restrict user access to the data. For filesystem, use the umount command to dismount. For LVM, use the vgchange -a n command to disable the volume group. If the volumes are controlled by applications, such as Oracle ASM, stop the applications using application-provided utilities. When the process is complete, reactivate LVM, file systems, and applications.