Networking Systems & Infrastructure

Data Center Engineer

Run the physical place where thousands of machines live and talk to each other.

This is usually a second role — most people arrive from support, systems or networking.

See this role on the career map → Find a path to it →

What you actually do

  • Design and build the switching fabric connecting thousands of servers
  • Plan rack layout, power draw and cooling before equipment arrives
  • Install, cable and commission hardware, and label it so it can be found again
  • Troubleshoot faults that could be optical, electrical or logical
  • Manage storage networks and the paths to them
  • Coordinate maintenance in an environment that is never supposed to go down

Technologies you may touch

Nobody uses all of these. Which ones depends entirely on the employer.

  • Arista EOS A network OS built around Linux and automation, common in data centres.
  • Cisco IOS The operating system on most Cisco routers and switches — configured from a command line.
  • VMware vSphere Software that runs many virtual servers on a smaller number of physical ones, and moves them around live.
  • BGP The protocol networks use to tell each other how to reach one another — it is how the internet decides where traffic goes.
  • VLANs A way to split one physical switch into several separate networks that cannot see each other.
  • Grafana / Prometheus / Zabbix Collects metrics from systems and shows you the graph that explains the outage.

Concepts you will learn

These transfer between employers and outlast any particular product.

  • Leaf-spine architecture
  • East-west trafficeast-west traffic — Traffic between machines inside the same network, rather than in and out of it.
  • Redundant power and cooling
  • Storage networking
  • Capacity planning
  • Structured cabling

Where this work happens

Colocation providers Cloud provider facilities Large enterprise data centres Financial trading infrastructure

You may enjoy this if…

  • You like being able to touch the thing you are responsible for
  • You enjoy work that is half design and half physical execution
  • You find scale genuinely interesting rather than intimidating

The honest downside

Data centres are loud, cold and often far from where you live. Some of the work is physically demanding, and the schedule follows equipment deliveries and change windows rather than office hours.

What it pays

Pay is the thing people most often get misled about, so here is where every number comes from — including the ones that are not really numbers.

Nearest official occupation

Median for the occupation

$96,800

Network and Computer Systems Administrators (15-1244)

What you actually start on

~$45,000–$65,000 from a hands-on or field background

Outlook

−4% projected — the on-premises version of this work is contracting toward cloud

There is no exact official occupation for this role. The figure comes from the closest one, which covers a somewhat different set of jobs.

Spans several BLS categories depending on the employer, from installer occupations through Network and Computer Systems Administrators (15-1244). Pay varies more by region than most IT roles, because the work is physically tied to specific facilities.

A median is the midpoint of everyone employed in that occupation, including people decades into their careers — so starting pay runs materially lower. Verify against the live BLS page before making a decision.

Source: U.S. Bureau of Labor Statistics · BLS OES, May 2024 release · figures are national and United States–specific; pay varies substantially by region and employer. Nothing here is adjusted for cost of living.

CertBlueprint earns affiliate commission on some study resources. It earns nothing from Data Center Engineer salaries, and no role is ranked, recommended or presented more favourably because of what it pays.

Where this leads

IT careers are a graph, not a ladder. These are the moves people actually make from here — each one reuses most of what you already know.

See where Data Center Engineer sits on the whole map →

Network Engineer

The logical side of what you are physically building.

Systems Engineer

If the servers interest you more than the fabric.

Cloud Engineer

The same infrastructure, rented rather than owned.

Often confused with

Titles overlap heavily in IT and tell you very little. Each of these puts Data Center Engineer beside another role on the same dimensions, with the practical differences underneath.

vs Network Engineer vs Field / Infrastructure Engineer vs Service Provider Network Engineer vs Network Administrator vs Systems Engineer vs Cloud Engineer

Try it this weekend, before you spend anything

Reading about work and doing it are different. Each of these is free, runs on the machine you already have, and takes under an hour and a half. Finding out you dislike it is a genuinely useful result — and far cheaper here than after an exam voucher.

Try the work · 45–70 minutes

Follow a packet

Free

Find out where your own traffic actually goes on its way out of the building — and what it looks like when it stops arriving.

Nothing to install · no account · open the steps

Before you start

Everything here runs against your own machine and connections you already make. Do not trace, scan or probe networks you do not own or have written permission to test — in many countries that is a criminal offence, not a grey area.

Built-in commands only. Nothing to install, no account, nothing to sign up for.

  1. Watch a name turn into an address

    Every connection starts by looking up a name. Run this against a site you use daily, then against a site in another country. Notice you get different addresses — sometimes several.

    Windows
    nslookup bbc.co.uk
    macOS
    dig bbc.co.uk +short
    Linux
    dig bbc.co.uk +short

  2. Trace the path out

    This lists every router your traffic passes through to reach that address. Read the hostnames down the left — you can usually see it leave your house, reach your provider, and cross into a backbone network.

    Windows
    tracert bbc.co.uk
    macOS
    traceroute bbc.co.uk
    Linux
    traceroute bbc.co.uk

  3. Find where the time goes

    Look at the millisecond figures. Somewhere there is a jump — 8ms to 90ms between two hops. That jump is usually the moment your traffic goes long-distance. Now trace somewhere far away and compare where the jump happens.

  4. Break it on purpose, then put it back

    Add a line to your hosts file pointing a site you use at 127.0.0.1, and try to load it. Watch how the failure looks from the browser — the error will not tell you what you just did. Then delete the line. This is the single most useful thing on this list: you have now seen a name-resolution fault from the user's side, which is what half of all "the internet is down" tickets actually are.

    Windows
    notepad C:\Windows\System32\drivers\etc\hosts   (run as Administrator)
    macOS
    sudo nano /etc/hosts
    Linux
    sudo nano /etc/hosts

  5. Optional — watch the actual conversation

    If you want to go further, install Wireshark, capture for ten seconds while loading one page, and filter for "http" or "dns". You will see the individual messages between your machine and the server. This is the one step that needs an install, which is why it is last.

This suits you if…

  • You kept going past step three without being told to
  • The latency jump made you want to know exactly where that hop was
  • You found the deliberate breakage satisfying rather than pointless
  • You wanted to know why a hop showed asterisks instead of a time

If you disliked it

If this felt like tedious bookkeeping, take that seriously. Networking and network security roles involve a great deal of exactly this — patient, methodical narrowing down, often at 2am. Finding it dull here is genuinely useful information, and it is much cheaper to learn it now than after a CCNA.

If it clicked, take it further: Foundations 2: configure a PC, then ping and pathping in NetDrill, a network simulator in your browser from the team behind CertBlueprint. Free, no account.

Try the work · 60–75 minutes

Design it on paper

Free

Map a real system you already own, decide what actually needs protecting, redesign it — and then be honest about what your design costs the people who have to live with it.

Nothing to install · no account · open the steps

Before you start

Map your own home network only. Everything here is pen and paper, so nothing you do can affect a system — but do not extend the exercise by surveying, probing or diagramming a network you do not own, including an employer’s, however harmless drawing it feels.

Paper and a pen. Deliberately no tools — the constraint is the point, because architecture is thinking, not diagramming software.

  1. Draw what you actually have

    Your home network, on one sheet. Router, every device, how each connects. If you did the exposure trial you already have the inventory; if not, list them from memory and then check — the gap between what you remembered and what is really there is itself the first finding, and it is the same gap every organisation has.

  2. Draw the lines nothing crosses

    Now mark what can reach what. On a normal home network the honest answer is everything reaches everything — your work laptop, your smart bulb, a guest's phone, the doorbell camera all sit in one flat space. Draw that reality, not the reality you would prefer.

  3. Name the thing that actually matters

    Of everything on that page, what would genuinely hurt to lose or have taken? Usually one or two things: the machine with your work on it, the drive with the family photos. Circle them. Everything else on the diagram exists, in security terms, mainly as a route toward those.

  4. Pick the worst device and follow it

    Choose the least trustworthy thing on the network — the cheapest smart device, the one that has not had a firmware update in three years. Trace, on the diagram, exactly what it can reach if someone takes it. That path is your blast radius, and drawing it is more persuasive than any risk score you could write down.

  5. Redesign it, on a second sheet

    Draw the version where that cannot happen. A separate network for untrusted devices. The important machine somewhere the doorbell cannot reach. Guest access that is genuinely separate. You do not have to build it — you have to be able to justify it.

  6. Now write down what your design costs

    This is the step that separates architecture from wishful thinking. What breaks? Casting to the TV probably stops working. Someone has to maintain two networks. A guest cannot print. Write the honest list, then decide which trade-offs you would actually accept and which you would not. If you cannot articulate the cost of your own design, you will lose every real architecture argument you ever have.

This suits you if…

  • Drawing the blast radius in step four was the moment it clicked
  • You enjoyed arguing with yourself about the trade-offs
  • You wanted to redraw it a third time to get it right
  • Working without tools felt freeing rather than limiting

If you disliked it

If the abstraction frustrated you and you wanted to go and actually configure something, take that seriously — architecture roles are largely diagrams, documents and persuading people, with someone else doing the building. That preference for hands-on implementation is a strength, not a deficiency, and it points at engineering rather than architecture.

If it clicked, take it further: SD-WAN migration (design) in NetDrill, a network simulator in your browser from the team behind CertBlueprint. Free, no account.

Try the work · 60–90 minutes

Walk the physical layer

Free

Stop treating the network as an abstraction. Measure a real radio signal in a real building, find out where it dies and why, and put your hands on the hardware everything else runs on.

Nothing to install · no account · open the steps

Before you start

For the hardware section: shut down fully, unplug from the mains, and hold a metal part of the case before touching components. Never open a power supply or a CRT — they store lethal charge even unplugged. Do not open equipment you rent, lease, or that belongs to an employer, and be aware that opening some laptops voids warranty. If in any doubt, do the wireless half and skip the rest; it is the smaller part of the trial.

Built-in wireless tools plus your own feet. The optional hardware section needs a computer you own and are willing to open — no purchase required.

  1. Measure what you have been assuming

    Find your current signal strength, right now, where you are sitting. Note the number and the units — dBm is a negative figure where closer to zero is better, and −50 is excellent while −80 is barely usable.

    Windows
    netsh wlan show interfaces
    macOS
    Hold Option, click the Wi-Fi menu — or open Wireless Diagnostics from Spotlight
    Linux
    iw dev wlan0 link    # or: nmcli -f IN-USE,SSID,SIGNAL,CHAN dev wifi

  2. Walk the building and write numbers down

    Take a reading in every room, and at the far corner of each. Write them on a rough floor plan. You are producing a coverage survey — the same artefact, at smaller scale, that a wireless engineer produces before a hospital or a warehouse deployment.

  3. Find the wall that eats your signal

    Look for the sharp drop, not the gradual fade. A gentle decline is distance; a cliff between two adjacent readings is something physical — a wall with foil-backed insulation, a mirror, a boiler, a fridge, a chimney. Go and identify the actual object. This is the moment radio stops being theoretical.

  4. Discover you are not alone on the air

    List the networks around you and the channels they occupy. Count how many are on the same channel as yours. Wi-Fi is a shared medium in a public commons — your neighbour's router degrades yours, and no configuration on your side can fully fix it. That constraint is the defining fact of wireless work.

    Windows
    netsh wlan show networks mode=bssid
    Linux
    nmcli -f SSID,CHAN,SIGNAL dev wifi list
    macOS
    Wireless Diagnostics → Window → Scan

  5. Trace one cable end to end

    Pick any cable in your home — the one from the wall to the router. Follow it physically to both ends. Where does it enter the building, and what is on the other side of that wall? Almost nobody knows. Documenting exactly this, across a building, is a real job that real people are paid to do because the records are always wrong.

  6. Optional — open something and name every part

    Power off, unplug, ground yourself, then open a desktop or an old laptop you own. Identify: the processor and its cooler, the memory, the storage, the power supply, the fans. Trace where the air enters and leaves. Ask where the heat goes. Now imagine ten thousand of these in one room — that question of heat, power and airflow is most of what data centre design actually is.

This suits you if…

  • Finding the exact wall that killed the signal was satisfying
  • You enjoyed being on your feet with a number in your hand
  • The shared-medium constraint interested you rather than annoying you
  • You wanted to open the case more than you wanted to read about it

If you disliked it

If the physicality felt like a chore — the walking, the writing down, the fiddling with hardware — that is worth knowing before pursuing wireless, field or data centre work, all of which are substantially physical jobs in real buildings, sometimes at height, in the cold, or at 4am. Plenty of superb network engineers want nothing to do with the physical layer and work entirely in routing and policy instead.

If it clicked, take it further: Read a port's story in NetDrill, a network simulator in your browser from the team behind CertBlueprint. Free, no account.

Then practice the work itself

A leaf-spine fabric from the underlay up: VXLAN, BGP EVPN and a gateway on every leaf. Each lab is graded on what the network does, not on the commands you typed.

NetDrill is a network simulator that runs in your browser, made by the team behind CertBlueprint. Free during the beta, no account. Links open in a new tab.

Certifications that fit this path

These come last for a reason. A certification is evidence for a direction you have already chosen — it is not the direction itself.

Foundation CompTIA Network+ Fundamentals first. Core Cisco CCNA The networking baseline for fabric work. Advanced Cisco CCNP Data Center The dedicated track for data centre networking and compute. Alternative Cisco Certified Field Technician Formalises data centre floor and smart-hands work before you move onto the networking track. Advanced Cisco CCIE Data Center The expert-level lab, for engineers already running large Cisco fabrics day to day.

Not sure whether this is actually you?

Reading about a role and enjoying the work are different things. The scenarios show you the problems instead of describing them, and tell you which ones you keep reaching for.

Try the scenarios →