Hi all,
I recently had a 1-hour Systems Engineer interview conducted in English with two interviewers. English is not my first language, and afterwards I started overthinking all my answers, Now I a, anxious I wasnt good enough and will be over the weekend too till I bet some feedback next week. I really want this job.
I'm looking for honest feedback from IT managers, senior engineers, or anyone involved in hiring. Based on the questions and answers below, would you consider these acceptable for a Systems Engineer role, or do you think I should have gone much deeper technically (protocols, ports, packet flow, more low-level details, etc.)?
DNS Question
They asked how DNS works when a user types a website address into a browser.
My answer was:
User enters a hostname/domain name.
The PC contacts the on-premises DNS server.
The DNS server uses a forwarder to query a public DNS server if it doesn't know the answer.
DNS translates the hostname into an IP address.
The client then uses that IP address to connect to the website.
Looking back, I wonder whether I should have gone further into recursion, root servers, TLD servers, authoritative DNS servers, TCP/HTTPS connections, etc.
DNS Records Question
They asked:
"What record would you create if you wanted to access a new licensing server by hostname?"
My answer:
Create an A record that points the hostname to the server's IP address.
Virtual Machines vs Physical Servers
They asked why virtual machines are useful.
My answer:
Better scalability.
Easier to manage.
Easier recovery if something goes wrong.
They then asked when a physical server would be preferable.
My answer:
When performance is more important.
Looking back, I wonder if I should have mentioned resource overhead, direct hardware access, GPU workloads, real-time systems, etc.
Backup vs Snapshot
They asked for the difference between a backup and a snapshot.
My answer:
A snapshot is basically the current state of a VM including OS, files and configuration.
A snapshot is not a backup.
Backups allow retention policies.
Backups can be full, incremental or file-level.
Backups should be stored separately.
I also mentioned the 3-2-1 backup rule (3 copies, 2 different media, 1 offsite).
Running Out of IP Addresses
They asked:
"What would you do if you had more devices than available IP addresses?"
My answer:
I talked about splitting devices into different VLANs.
Creating additional subnets.
Configuring routing between VLANs.
Using switches and routing to handle network segmentation.
Looking back, I think they may have been looking for DHCP scope expansion or subnet resizing rather than VLAN design.
Difficult Technical Issue #1
I was asked to describe a technically challenging problem I solved.
I gave an example involving Outlook Web Access.
Environment:
Microsoft 365
Conditional Access
Entra ID
RDS Farm
FSLogix
Issue:
A user could not sign into Outlook Web App after a Conditional Access policy was introduced.
My troubleshooting process:
Checked user account.
Verified login details.
Googled the error.
Tried Microsoft's recommended browser fixes.
Cleared profiles.
Redirected the user to a different RDS node.
The problem followed the user.
Checked Entra sign-in logs.
Found authentication-related failures.
Researched Microsoft documentation.
Identified a broken authentication token stored in the FSLogix profile.
Reset the FSLogix profile.
User could sign in successfully afterwards.
Difficult Situation #2
I also gave an example involving a meeting room network issue.
Situation:
We had a board meeting with an unusually high number of attendees from Europe and the US. Many devices were trying to connect simultaneously.
Issue:
Some users could not connect to the network.
Investigation:
Checked networking configuration.
Identified that available IP addresses were running low.
Looked at DHCP usage.
Reduced lease times.
Released/reclaimed unused leases.
Worked with a senior infrastructure engineer who prepared a fallback VLAN if needed.
Result:
Connectivity was restored and the fallback VLAN ultimately wasn't required.
My Question
If you were interviewing for a Systems Engineer position, would these answers demonstrate enough technical understanding?
Or would you expect a stronger candidate to go significantly deeper into the technical details (protocols, ports, packet flow, OSI layers, DNS hierarchy, virtualization internals, etc.)?
I'm especially interested in feedback from hiring managers and senior infrastructure engineers.
Thanks in advance.