Host-based backup mostly comes in two types, known as Agentless Backup and Agent-based Backup is a new whir in the field of data recovery. People usually know the agents as small applications installed on the host server to run particular functions in a specific manner.
These applications (agents) are installed on the host server that the admin is required to backup. Agentless backup is the backup without the use of such agents. Whereas, Agent-based backup is backing up the information with the help of an agent or more.
Quite a few vendors claiming that they provide agentless backup, actually add an agent at the beginning of the process and delete it right before the entire backup is made. Surely the rest of the process does not involve any agents, but, in the end, you would not call it an agentless backup.
The need for Agent-based backup
When choosing an Agent-based backup as a service, you would have to reboot your system after the install because the snapshot driver resides at the operating system kernel level and hence requires the OS to be restarted.
A plus point of an agent-based backup is, since it is loaded with the OS stack, it offers increased control and visibility of the host system that would not be immediately available in the case of Agentless backup. For example, agent-less backups typically need to traverse the file system to determine changes for incremental/differential backups.
This traversal could take longer and be more complex than compared to Agent-based backup which has CBT (Change Block Tracking) and the kernel level.
In comparison, Agentless backups rely more on network resources to transmit application commands across the network as well as data between the target and storage device. If your local network bandwidth is hardly enough to fulfill your needs, then additional network traffic from agent-less backups could impact local network performance.
Every time a user scheduled backup is acted out, Delta Encoding deltas are transmitted to a backup archive efficiently creating a virtual Disk Image. Continuous Data Protection can restore previously captured disk images to another disk efficaciously replicating the structure and contents to a new disk. Individual files inside of a disk image can be restored to their original location or an alternate computer.
Frequently Asked Questions
Q1. What is the difference between host level backup and guest level backup?
The DPM protection agent can be installed at both the host and guest level to ensure data protection. At the host level, the agent is installed on the Hyper-V host server or cluster and provides protection for all virtual machines and data files that are running on that host. On the other hand, at the guest level, the agent is installed on each virtual machine to protect the specific workload present on that particular machine.
Q2. What is VMDK backup?
When it comes to backing up a VMDK volume, it typically involves duplicating the virtual disk and transferring it to a different location. However, there are crucial points to consider. Many commercial backup solutions concentrate on creating VM clones or snapshots and may not enable the backup of virtual disks independently.
Q3. What are the different types of virtual machine backups?
There are 03 types of VM backup: full, differential, and incremental. A relatively new addition to the mix is the forever incremental backup.