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In COMMVAULT, only one primary copy and MANY SORTS of auxiliary/secondary copies are permitted. There are various types of copies.

• Selective Copy: You can copy specified full backup jobs from a SOURCE copy, which can be either a primary or a synchronous copy. Selective copy allows for more efficient tape rotation.
• Inline copy: During the Backup Phase, both the Primary and Secondary copies are written to storage. Backups will fail if the secondary storage does not have ADEQUATE space.
• Synchronous copy: A synchronous copy copies all of the data from the primary.

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DATA encryption keys are encrypted with the CLIENT's RSA public key and stored in the database. Depending on the settings, the client's RSA private key is encrypted with either a built-in passphrase or a passphrase provided by the USER.

No, the data is not double-encrypted. Data that has been encrypted by HDPS Monitor SOFTWARE is FLAGGED. The FLAG is checked during an auxiliary copy operation, and if the data has already been encrypted, no ADDITIONAL software encryption is used. During the auxiliary copy PROCEDURE, only data that has not been encrypted by HDPS will be encrypted.

Yes, data is effectively randomised when backup procedures are PERFORMED using encryption. This means that while compressing encrypted data, compression METHODS will be less effective. As a result, there will be a visible DIFFERENCE in the compression ratio when this data is written to the media.

For example, a tape with a native capacity of 110GB that was formerly compressed to 190GB may now only be able to write 124GB to the same tape when encryption is used. The amount of data that can be written to tape depends on the type of data that is being written. Image files will not be compressed because they are already compressed, however, a TXT file will be compressed heavily.

Only in the case of asymmetric cryptography, where DISTINCT keys are used to encrypt (with the private key) and decrypt (with the public key), is a Certificate Authority required. There is no need for a certificate or a certificate authority because all of our encryption is symmetric (the same key is used to encrypt and decrypt).

When exchanging DATA over insecure lines (such as the INTERNET), and the IDENTITY of the entities on both ends is unknown, asymmetric crypto is employed. The CA helps VALIDATE the validity of the sent data, ensuring that malicious material is not sent. This issue does not exist in our situation because both endpoints have known entities.

A snapshot copies the virtual machine's DISK file to maintain its current state. It is used as a backup system. Create a snapshot if you need to save the configuration of a virtual machine so you can revert to it later if something goes WRONG. A clone, on the other hand, is a complete copy of the virtual machine. Cloning is the sole OPTION if you need to create a new virtual machine that will run on its own.

• Storage Policy: The storage policy determines where the data is saved and how long the snapshot will be kept. Copies can be found within a Storage Policy. In the IRM environment, these copies define retention for the designated storage devices. Within IRM, there are just two versions of interest. The Primary Snapshot Copy and the Primary Copy are two different copies of the same thing. The Primary Snapshot Copy merely specifies how long the SNAPSHOTS will be kept and which MediaAgent will be cataloguing them. The Primary Copy specifies the location of the catalogued indexes.
• Job Manager: Displays all information about a running job, including data protection, recovery, and Auxiliary copy, as well as settings and media usage. Snapshot jobs can be LAUNCHED, suspended, restarted, and cancelled by the Job Manager.
• Backup Set: A backup set is a sub-container present within each of these agents. The backup set is the client's overall container. The most straightforward approach to comprehending a backup set is to relate it to the context of the system being snapped in the environment. The backup set for the file system iDataAgent is the fundamental physical system storage environment, whereas the backup set for these two database agents is the Exchange Information Store or SQL instance. An overall vCenter is the backup set in a Virtual Context since it encompasses numerous ESX servers that house and manage virtual machines.
• Subclient: The SMALLEST subset of a client is called a subclient. From the perspective of a Windows host, it may be a single folder, a single database, a single Virtual machine, or a single LUN or drive letter (regardless of how many LUNs are meta-LUN'ed to produce one huge LUN pool). Sub clients are backup set definitions that are related to Storage Policies, which define the snapshot data's retention and location.
• Collect Files: During an IntelliSnap job, Collect Files are smaller text files that will gather information on what is on each of the clone/snapshots. The original information lying on the snapshots is indexed by the collect files saved under the TASK result directory under each of the IRM clients when the snapshot is mounted to be catalogued. Once the cataloguing is complete, the information will be given immediately to the MediaAgent who will store it in indexes for a longer period of time. These indexes will remain on the MediaAgent for the duration of the snapshot's retention period, either in the local MediaAgent index cache or in the disc library set up to protect the indexes and the CommCell database backup.

The following events occur when the DDB backup job starts:

• For a few seconds, all communication with the active DDB is halted. To ensure that the DDB is in a dormant stage, the information in memory is committed to memory.
• The DDB process uses VSS (Windows) or LVM (Linux) snapshots to make a snapshot of the volume.
• The file systems Extended 3 File System (ext3) and VERITAS Volume Manager (VxVM) are also supported on the Linux platform.
• All communication with the DDB is resumed when the snapshot is created, and the DDB is automatically backed up from that snapshot.
• If a VSS (Windows) or LVM (Linux) snapshot fails, the DDB backup falls back on a live volume backup. 
• The snapshot is erased after a successful DDB backup. The Job Controller displays the DDB Backup job in a running condition at this point.
• If the DDB MediaAgent restarts during a DDB backup job, the job is marked as Pending. The DDB backup job resumes from the beginning after the restart.
• The DDB backup JOBS for the AUXILIARY copy OPERATION are disabled by default, and these jobs appear as UNAVAILABLE when viewed from the primary copy.
• Allowing DDB Backup Tasks from Being Copied to Secondary Copy describes how to enable or prohibit DDB backup jobs from being copied to secondary copy during the auxiliary copy procedure.