Some statements to consider

Here are a few statements that I have collected.

Below are some system design statements to consider whenever designing and implementing a system/solution in your organization. When things goes wrong - will it be a lunch break or an all-week activity?

"No news is not good news, it means you're ignorant" - wise old DevOp guy

Monitor: Second to second. Computers were made for repetitive boring tasks. Monitor the alarm systems as well.

Automate: Are you doing the same thing? You're not automating enough.

Watchers: As many as sensible. No one likes On Call. Plan for the no answer. It will happen even to the best.

Idiots: Learn to love 'em. They'll break your stuff in new and breathtaking ways. Save killing them for later. After you fix it.

Test: Frequently. Synthetic tests are your friend. Monitor them.

Redundancy: As much as you have budget for. Document when its not enough. You'll need it later when the PHBs call.

Monoculture: To be avoided where possible. Accept when it's not possible.

Document: You stopped? Oh, bleep!

Logs: Read 'em. An attacker can fail a million times. You get one chance to get it right.

Failure: You. Will. Fail. If you never fail, you're not doing anything.

Hosting: Don't keep all your eggs in the same basket or in a basket shared with many others, at worst with your competitors.

Dependencies: Be very afraid of the domino effect of system interdependency. It only takes one to fall to pull down all your systems if all systems depends on one common library/service. (Think of the recent Log4J issue)

Segmentation: Isolate services from each other in different servers and VLANs and use internal firewalls to be specific about which traffic that's permitted between the segments. Who needs every printer on the net to be visible from all sites? Printers are a local concern and in a few cases for a few central systems.

The Internet: Don't trust that it's there, and it's never safe. So never run systems dependent on any service on the net. At best the provider will leave some warning before they go away forever.