3 ms·
High level items: - Resiliency of all hardware, software, interconnects i.e. no single points of failure; - Isolation of the various routes, such that you can
by benjaminwootton 13y ago
High level items:
- Resiliency of all hardware, software, interconnects i.e. no single points of failure;
- Isolation of the various routes, such that you can pull any plug in the system and there is always a route through;
- An application architecture that supports horizontal scaling, clustering, load balancing, error conditions, enough asynchronicity;
- Enough capacity such that if things start failing, the rest of the system can handle the load;
- Tooling and environments that support stuff such as intraday deploys and rollbacks, including database migrations;
- QA and testing processes to ensure catastrocphic bugs do not slip through!
These are all achievable, but it's when problems start interacting that stuff slips through the cracks.
- waps 13y agoLegal items. Alternatively: The cheat everyone else is using. 1) contractually provide a 100% SLA 2) the "benefit" you give the customer when you don't provide 100% of uptime for a given period is 10% price reduction for that period only 3) To add insult to injury, make the period a day or even an hour. 4) Downtime is only downtime after reception of an email from the designated customer contact, and only if it wasn't resolved at the time they actually noticed. That customer contact must be a person, ready and able (legally allowed) to answer questions and make choices. This is how a lot of ISPs are doing it. Amazing how many people consider this a 100% SLA. Then the ISP is down for weeks, and then they get to pay $50 less on a $5000 bill ...