Backup is not a tool. Backup is not a software you can buy. Backup is a strategy you need to study and implement to be able to solve your specific problems.
If you are using Proxmox, ZFS is one of the best local storage options. You can easily backup your lxc containers using Borg.
Lxc containers are fast, small and useful. Proxmox Backup Server is quite slow with them, so here's how to perform a fast and efficient backup using Borg.
Many people think that it is enough to ensure that the storage medium is redundant - and you are fine. WRONG!!!!!
I have already dealt with the problem of performing a correct backup. This time I will give you some insights into how I make backups and how I am able to guarantee a certain level of security.