What is a backup?#
A backup is a copy of your data kept apart from the original. When something breaks, you can return to a healthy state from that copy. A backup is like insurance: you don't notice it until you need it.
What can go wrong?#
- Accidental deletion by you or a colleague
- Hard drive or server failure
- A hacked site and ransomware
- A failed plugin or system update
The 3-2-1 rule#
A simple and well-known principle:
- At least three copies of your data
- On two different types of storage
- One copy off-site (for example cloud storage or an external drive)
Types of backup#
- Full: copies everything.
- Incremental: saves only the changes since the last backup and takes less space.
WordPress example#
A full site backup includes the files (theme, plugins, images) and the database. If you take only one of them, the restore will not be complete.
Restore testing#
A backup you have never tried to restore may not work. At regular intervals, restore it once on a test server.
A common mistake#
Keeping the backup only on the same server. If the server is hacked, the drive burns out or the hosting company closes the account, the backup is lost with it. Always keep one copy elsewhere and protect access to it with a strong password.