A local backup is the first step to protecting your data. You bolster your plan by storing copies on different media to protect against any single point of failure. For example, by having a copy of your PC backup stored on a Synology NAS.
Having a copy of your data off-site is generally the most difficult and costly step. However, it is extremely important, as local backups do not protect against fire, natural disaster, or theft of all your equipment.
A simple way to add off-site protection is to back up your Synology NAS to cloud storage, such as Synology C2 Storage. For larger deployments, setting up a disaster recovery site at a remote datacenter or branch office is often more cost-efficient.
3
Have at least 3 copies of your data
2
Keep these copies on 2 different media
1
Store at least 1 copy off-site