Intermediate · 14 lessons
Servers
Servers are powerful computers designed to run 24/7 and serve data to clients. Web servers host websites, database servers store data, mail servers handle email, and file servers manage storage. Understanding server hardware and software is core to hosting and DevOps.
Key Concepts
Key Takeaways
- ✓ Servers run specialized OS and software to serve clients over the network.
- ✓ Virtualization splits one physical server into many isolated VMs.
- ✓ Data centers provide power, cooling, redundancy, and network connectivity.
- ✓ Monitor CPU, RAM, disk I/O, and network — bottlenecks cause downtime.
Lessons in This Topic
Server Hardware Basics
CPU, RAM, storage, and network in datacenters.
Web servers need fast CPUs for PHP/Node, ample RAM for caching and databases, SSD storage for I/O performance, and gigabit+ network ports. Enterprise hardware includes dual power supplies, ECC RAM, and hot-swappable drives. Colocation means you own hardware in a rented rack space.
Physical vs Virtual Servers
Bare metal compared to VM workloads.
Physical (bare metal) servers offer maximum performance with no hypervisor overhead — ideal for databases and high-compute tasks. Virtual machines share physical hardware via hypervisors (KVM, VMware, Hyper-V). VMs are cheaper, faster to provision, and easy to snapshot/clone.
Data Center Tiers & Redundancy
Tier I–IV, N+1 power, and geographic redundancy.
Tier IV data centers offer 99.995% uptime with fully redundant power, cooling, and network paths. N+1 means spare capacity if one component fails. Multi-region deployment protects against natural disasters. SLA credits compensate for downtime below promised levels.
Web Server & Application Stack
LAMP, LEMP, MEAN, and modern stacks.
LAMP = Linux + Apache + MySQL + PHP (WordPress standard). LEMP swaps Apache for Nginx. Modern stacks add Redis caching, Node.js APIs, and container orchestration. Choose stack based on app language, traffic patterns, and team expertise.
Server Monitoring & Maintenance
Health checks, patching, and capacity planning.
Monitor with tools like Nagios, Datadog, or Prometheus. Set alerts for CPU > 80%, disk > 90%, memory pressure. Apply security patches monthly. Plan capacity before traffic spikes — Black Friday, product launches. Maintain off-site backups and test restores quarterly.