49How do fail2ban and CrowdSec protect an SSH or web server, and what attacks do they not stop?▼mediumNewCloudflareAmazonGoogle◆ premiumBoth tools read logs and ban addresses after the fact. Knowing what that design can and cannot see is the whole answer, and most candidates call it an authentication control.Open full answer →
50How would you secure SSH access to a fleet of Linux servers: keys, SSH certificates, bastions and revocation?▼mediumNewGoogleAmazonCloudflare◆ premiumTurning off passwords is the easy half. The interview is about the other half: how keys are issued, how long they live, how a host proves itself, and how you cut someone off at 5pm on a Friday.Open full answer →