Every system administrator should have a server backup of some form. For on-premise servers, it may be an external storage device, either physically connected to the server or stored within a network-attached storage (NAS) device. For remote servers, you can still use a local storage or lease a separate server for backups.
In some cases, your web host may provide backup server space at an additional monthly cost to your own server. These services, however, may not always be the best deal, and you would still have to trust the same company to keep your data secure on both servers. If those servers are both housed in the same data center, that may pose another problem, should a natural disaster strike.
An affordable alternative is what many call the “low end box”. This is a server with not particularly flashy system specs. Usually they have little RAM and a slower processor when compared with modern medium and high-end servers. But a low end box is perfect for backup.
What you get with a low end box is either a dedicated server or VPS that gives you the bare minimum you need to have full access rights to a server. In other words, you will be the root system administrator. The server itself may not be anything sophisticated, but the point is that you have root access to it and can SSH into it, perform backups, and do anything else you need to do.