Ongoing Linux Server Hardening

I run a small fleet of production machines—one dedicated server and several VPS instances—all on Linux. The mix includes Ubuntu, CentOS and a newer AlmaLinux image, so you’ll need to be comfortable switching hats between distributions. Immediate priority One VPS is currently being hammered by a DNS amplification flood. Your first task is to trace the vector, shut it down, patch or re-configure the resolver, and verify the abuse can’t be repeated. Ongoing scope Once the dust settles I want you to own the security posture of every server: apply kernel and package updates, tighten SSH, write sensible iptables / nftables / firewalld rules, and put continuous monitoring in place. Feel free to suggest and deploy tools such as Fail2ban, CSF, Snort or Suricata so long as they stay lightweight and production-safe. Deliverables for this engagement • DNS flood blocked, resolver no longer open for recursion • Baseline firewall rules applied on every host • Brief hardening report and change log (text or Git) • Zero avoidable downtime during the process If everything runs smoothly there’s plenty of follow-on work—regular audits, backup automation, and future infrastructure tweaks.

Project ID: 40178082