Table of Contents
LiveBackup
LiveBackup refers to a technology integrated into nxmBackup to keep possible data loss as low as possible. A conventional backup is carried out according to a certain schedule at fixed times. If the backed up virtual machine fails, the most recently performed backup must be used to restore it. All changes that have occurred within this machine since the last backup are irretrievably lost.
LiveBackup addresses exactly this problem. Here, too, backups are carried out according to a fixed schedule, but all changes to the virtual machine being backed up between backups are also recorded. If the situation arises where a restore needs to be started, this virtual machine can be restored to the second at any point in time between two backups. Data loss during recovery can be reduced to almost zero.
Advantages
Advantages of LiveBackup over classic backups:
- Data loss in the event of a disaster can be minimized
- “Recovery Point Objective” (RPO) ideally is almost 0
- In the event of a disaster, the time until recommissioning can be significantly shortened (“Recovery Time Objective”)
Disadvantages
Disadvantages of LiveBackup compared to classic backups:
- Depending on the number of I/O writes within the virtual machine, the backup created by nxmBackup can be very large because every write is recorded
- Depending on where the backups are stored within your own infrastructure, LiveBackup can generate high I/O or network load
Recommendations
Basically, the following recommendations should be considered when using nxmBackup:
- LiveBackup should not be used on virtual machines where high I/O write rates are expected
- The backup target should be accessible at least with the same write and read rates as the memory of the virtual hard drives of the virtual machine being backed up
- It should be noted that the storage required for a LiveBackup can increase significantly. Therefore, a size limit must be set when creating a job. This storage size should be at least available on the backup target.
- When restoring from a LiveBackup to a certain point in time, it should be noted that, for example, a file that was written to the virtual hard drive shortly before that point in time may not yet be visible or not completely visible in the restored machine. A slightly later point in time should be chosen for the restoration.