Technical Support Engineer interview questions and answers

Work from the bottom up instead of guessing. First the scope: is it one device or every device, and wired or Wi-Fi? Then the physical layer: are the router's lights normal, is the cable plugged in, and does restarting the router help? Next the PC's address: run ipconfig. A 169.254.x.x address means it didn't get one from DHCP. If it has a proper address, ping the default gateway, then a public IP such as 8.8.8.8, then a website name.

Where it fails tells you where the problem is: the gateway failing points to the local network, the IP working but names failing points to DNS. Note each result in the ticket.

ping checks whether a device answers and how long the reply takes; timeouts or high times show a connection or speed problem, though some servers block ping on purpose. ipconfig /all shows the PC's IP address, subnet mask, default gateway, DNS servers, MAC address and whether DHCP is on. tracert lists each router on the path to a destination, so you can see where the traffic stops or slows down. nslookup asks a DNS server what IP address a name resolves to, which tells you whether DNS is working and which server answered.

On Linux and macOS, the equivalents are ip addr, traceroute and dig; nslookup is there too, and ping keeps running until you press Ctrl+C.

If an IP address answers but websites don't, the connection works and name resolution is failing, so it's almost always DNS. Confirm it with nslookup google.com: a timeout or error means the DNS server isn't answering. Check which DNS servers the PC uses with ipconfig /all; a wrong or unreachable server, often set by hand or by a VPN, is common.

Fixes: clear the cache with ipconfig /flushdns, set the adapter back to get DNS automatically, or try a known public DNS server temporarily to prove the point. If the company's own DNS server is down, it affects many users and becomes a bigger incident. Also rule out a proxy setting in the browser.

Change one thing at a time. Check the link light on the PC's network port and on the wall socket's switch port; no light usually means a physical problem. Swap the patch cable with a known-good one. Plug the user's laptop into a colleague's working socket: if it works, the PC is fine and the problem is their wall point or switch port. Plug a known-good laptop into the user's socket to confirm.

If the socket is dead, a cable tester shows a broken run, and the network team can check whether the switch port is disabled, shut down by port security, or on the wrong VLAN. If nothing works anywhere, check the PC's network adapter and driver.

Use the agreed definitions, not the label. I'd ask questions that measure impact and urgency: how many users are affected, whether they can work at all, whether there's a workaround, and whether there's a deadline, such as a payroll run or a live event. Those answers map to the priority matrix in our SLA, so a single user's cosmetic issue stays low even if it's marked urgent.

I'd explain the priority politely, with the reason and when they'll hear from us, so they don't feel ignored. If they think it's wrong, they can give new facts and I'll change it. Repeated over-flagging can go to their account manager.

The SLA clock measures how long we take to respond to or resolve a ticket. Pausing it stops the time counting while the delay isn't in our control, usually by putting the ticket in a status like Pending Customer or On Hold.

It's fair when we're genuinely waiting on the customer, for example for logs, a screenshot or a time when their system is free, or when the customer has asked us to wait. It isn't fair when we're waiting on our own engineering team or a vendor we chose, because that delay is ours. Always add a note explaining the pause, and follow up; pausing to avoid a breach damages trust and reports.

The P1 comes first, because a service down for a major customer outweighs ten minor issues. But I wouldn't let the others breach silently. I'd tell my lead straight away so the P3s can be shared out among the team, and spend a few minutes sending each of those customers a short update with a realistic time, which often meets the response target.

On the P1, I'd follow the major incident process: open a bridge or channel if needed, involve engineering early, and update the customer at agreed intervals, even when there's no news. Afterwards, the breaches and the cause of the outage go into the review.

Escalate when it looks like a real defect in the product, needs access or code changes support doesn't have, affects many customers, or is close to breaching its SLA after you've used the troubleshooting guides. Check first that it isn't already a known issue, so you can link to it instead of raising a duplicate.

A good escalation saves a round trip: a clear summary, the customer and business impact, product version and environment, exact steps to reproduce, expected and actual results, logs, error messages and timestamps, and what you've already tried. Say how urgent it is and why. Keep owning the customer: they hear from you, not from engineering.

Response time is how quickly support must acknowledge and start working on a ticket, such as within 30 minutes for a P1. Resolution time is how quickly the problem must be fixed or a workaround given, such as within four hours. A ticket can meet one and breach the other.

An SLA is an agreement with the customer. An OLA, an operational level agreement, is an internal agreement between teams that helps meet the SLA, for example the database team agreeing to pick up escalations from support within an hour. An agreement with an outside vendor for the same purpose is an underpinning contract. Use the exact targets from your company's SLA when you answer.

Write notes so that anyone could pick up the ticket without calling you. Include what the customer reported in their words, the error messages, what you checked and the result of each step, what you changed, and what the next step is and who owns it. Add the time of any call or promise made to the customer.

Keep customer-visible replies separate from internal notes, and write the replies in plain language. When resolving, record the actual cause and fix, not just "fixed" or "working now", because that is what makes reports and the knowledge base useful. Never paste passwords or other sensitive data into a ticket.

Incident management restores service as fast as possible: the user's application crashes, you find a workaround, they're working again, the incident is resolved. Problem management finds and removes the underlying cause, so incidents stop recurring. If twenty customers report the same crash after an update, those are twenty incidents linked to one problem.

A known error is a problem whose cause is understood, with a documented workaround, but not yet a permanent fix. It's recorded in the known error database so support engineers can resolve new incidents quickly using that workaround. The permanent fix usually goes through change management. Showing you'd spot a repeating pattern and raise a problem ticket is what interviewers want.

Disk: df -h shows each filesystem's size and how full it is, and du -sh * shows how much space each item in the current directory uses. Memory: free -h shows used and available memory and swap. Processes: top, or htop if installed, shows live CPU and memory use per process, and ps aux | grep name finds a specific one. Logs: tail -f /var/log/syslog (or /var/log/messages on Red Hat-based systems) follows a log live, less opens a large file to scroll and search, and grep -i error filters lines.

On systems using systemd, journalctl -u servicename shows a service's logs.

Every file has an owner, a group and permissions for three sets of people: the owner, the group and others. Each set can have read (r), write (w) and execute (x). ls -l shows them, for example -rwxr-xr-x.

In number form, read is 4, write is 2 and execute is 1, added together for each set. So chmod 755 gives the owner 7 (read, write, execute) and the group and others 5 (read and execute): typical for scripts and directories. 644 gives the owner read and write, and everyone else read only, typical for normal files. On a directory, execute means you can enter it. chown changes the owner and group.

Check the service first: systemctl status appname shows whether it's running, when it stopped and the latest log lines. journalctl -u appname -n 100 shows more, and the application's own logs often explain the error. Then check the usual causes: a full disk with df -h, which stops many applications from writing; memory with free -h, and the kernel log (dmesg or journalctl -k) for the out-of-memory killer; and whether the port is listening with ss -tlnp.

After fixing the cause, restart with systemctl restart appname and confirm it stays up. If it should start at boot, systemctl enable it. Note what you found in the ticket, especially if it may happen again.

Deflection means a customer solves their problem through self-service, such as a help article, an FAQ or a chatbot, instead of raising a ticket or calling an agent. The deflection rate is the share of customers who used self-service and didn't need to contact an agent.

It's tricky to measure honestly, because a customer who gave up and left looks the same as one who was helped. So combine it with other signs: whether the same customer contacts support within a few days, "Was this helpful?" ratings on articles, chatbot conversations that end in a hand-off, and the searches that return no results. A good deflection rate with rising complaints means self-service is failing quietly.

The customer should never have to repeat themselves. A good hand-off passes the agent the whole conversation, the customer's details and account, what the bot already suggested and the issue category, so the agent can start from where the bot stopped.

It should also happen at the right time: when the customer asks for a person, when the bot doesn't understand after a couple of tries, when the customer is clearly upset, or for sensitive matters such as payments, complaints or account security. Tell the customer honestly how long the wait is, and offer a callback or email if no agent is available. A bot that blocks people from reaching a human damages trust.

Find out where the wrong answers come from. Review the conversations marked unhelpful and the ones that ended in an agent hand-off, and group them by topic. Most often the knowledge base the bot answers from is outdated, contradictory or missing articles, especially after a product release.

Then fix the source: update or remove old articles, give each article an owner and a review date, and make article updates part of every release checklist. Agents should be able to flag a wrong answer easily. For an AI chatbot, limit it to answering from approved articles, and hand off when it isn't confident rather than guessing. Track the same complaint topics afterwards to confirm it improved.

Keep it to about a minute and link it to support. "I'm a [degree] graduate from [college]. I've always liked solving technical problems and explaining them simply; in college I [helped run the lab, set up networks for events, or supported classmates' laptops]. I've learnt networking basics, Windows and Linux, and [a course or certification such as CCNA]. I'm comfortable speaking with people and staying patient when they're stressed. Now I'm looking for a technical support role where I can work with customers and keep building my technical skills."

Speak clearly and at a steady pace: in support interviews, how you say it is being assessed too.

Use plain words, an everyday comparison, and focus on what it means for them. For example, for a DNS problem: "Your internet connection is working, but the service that turns website names into addresses isn't answering, a bit like having a phone with no contacts list. I'll point your computer to a working one, and websites will open again." Then tell them what you'll do, what they need to do, and how long it will take.

Check their understanding by asking them to try a step, not "Do you understand?". In the interview, try explaining something from your own experience this way.

Stay calm and don't take it personally. Let them finish, acknowledge the impact ("I understand this has stopped your team's work for two days"), and apologise for the experience without blaming colleagues. Then take ownership: summarise the problem, say exactly what you'll do and by when, and do it.

If they still want a manager, don't block it; offer it politely and brief your manager first so the customer doesn't repeat everything. Record the conversation in the ticket. Interviewers like an example: "A customer once [situation]; by [action], they stayed and later gave positive feedback." Never promise refunds or fixes you can't authorise.

Show you know the numbers can pull against each other and that you aim to solve the problem once. "I try to resolve issues at the first contact, because a quick close that gets reopened costs more time and hurts satisfaction. I use the knowledge base and templates to save time on routine tickets, so I can spend longer on difficult ones. If a ticket is taking too long, I escalate rather than hold it." Add a result: "Last quarter my first-contact resolution was [figure] and my reopen rate was [figure]."

Never suggest closing tickets early to hit a target; interviewers treat that as a warning sign.

Be honest, and show you've thought about what night shifts involve. "Yes. I understand the role follows the customers' working hours. I've thought about the routine it needs, sleep, travel and food, and I'm prepared for it. I'm comfortable speaking English on calls and in writing, and I'm working on [a clear, neutral accent, writing concise emails, or understanding different accents]."

Ask whether the shifts rotate and whether the company provides transport, which many do for night shifts. If you have a real constraint, say it now: accepting and then struggling is worse for both sides.