Chapter 2

Server Anatomy

CPU, RAM, NICs, PSU redundancy, form factors.

Learning objectives

  • Name major server components and their roles
  • Compare rack vs tower form factors
  • Understand redundant PSU and NIC teaming basics

Inside the chassis

A 1U rack server in Swift Host’s Edmonton facility might host Workshop Co.’s production stack. Key components:

ComponentRoleWorkshop Co. consideration
CPUCompute — cores and clock speed8–16 cores for PHP + image batch jobs
RAMFast workspace for apps and cache32–64 GB for MySQL + PHP-FPM pools
StorageOS, database, uploadsNVMe SSD primary; see RAID chapter
NICNetwork connectivityDual 1 Gbps or 10 Gbps to top-of-rack switch
PSUPower supplyDual redundant in data centre builds
BMC/IPMIOut-of-band managementSeparate management port on dedicated VLAN

Form factors

1U / 2U rack

Standard data centre — dense, rail-mounted

Tower

Office or edge — quieter, less dense

Blade

Enterprise chassis — shared power/network midplane

Workshop Co.’s dedicated host is almost certainly 1U rack in colocation — not a tower under the shop desk.

Worked example — read a spec sheet

Swift Host offers “EDM-BM-01”:

  • AMD EPYC 7313P — 16c/32t
  • 64 GB DDR4 ECC
  • 2× 960 GB NVMe + hardware RAID controller
  • 2× 1 Gbps public, 1× IPMI port

ECC RAM detects and corrects single-bit memory errors — recommended for 24/7 production. NVMe beats SATA SSD for database random I/O — relevant when class photo uploads spike.

Thermal and power

Data centres quote power by rack unit and circuit (e.g. 0.5 kW sustained). Oversizing CPU without cooling headroom gains nothing — follow provider guidance.

Try it yourself — bottleneck guess

Workshop Co. complains thumbnail generation is slow during uploads. CPU averages 20%, disk queue high, RAM 40%. What is the likely bottleneck?

Answer

Disk I/O — high queue depth with low CPU suggests storage saturation. Upgrade to faster NVMe, tune batch jobs, or add RAM for cache — verify with iostat before buying hardware.

Quick quiz

  1. What does 1U mean?
  2. Why ECC RAM for servers?
  3. What is the BMC used for?
Answers
  1. One rack unit — ~44 mm height in a 19-inch rack.
  2. Error correction reduces crashes from cosmic rays / bit flips on always-on hardware.
  3. Baseboard Management Controller — IPMI interface for remote management.