The maintenance that matters most.
WHY IT MATTERS
Most compromises exploit known vulnerabilities with available patches.
Unpatched software is the primary cause.
WHAT TO UPDATE
The operating system Installed services Your control panel Applications you run
HOW OFTEN
Security updates promptly. Other updates on a schedule.
AUTOMATIC UPDATES
For security patches, generally worth enabling.
For major version upgrades, no. Those need testing.
BEFORE ANY SIGNIFICANT UPDATE
Snapshot or back up.
Updates occasionally break things.
WHAT TO TEST AFTERWARDS
That sites load That email works That scheduled tasks run
THE COMMON FAILURE
A server set up carefully and never updated again.
It works fine until it does not, and then it is compromised.
WHAT TO SET UP
A reminder, or automated security updates, or a managed service.
Relying on memory does not work.