Introduction
No matter how carefully you design an Azure environment, sooner or later, a virtual machine (VM) will misbehave. Maybe it won’t start, maybe it’s running slowly, or maybe a user insists “the server is down” while all your dashboards are green. As a system administrator, your value often shows not when everything runs smoothly, but when you can diagnose and fix issues quickly.
Over the years, I’ve had my share of Azure VM challenges, from network misconfigurations to storage bottlenecks. What I’ve learned is that troubleshooting Azure VMs requires both a structured process and a willingness to dig deep. For recruiters, demonstrating this skill highlights your ability to problem-solve under pressure — a quality every IT team needs.
Step 1: Start with the Basics
Before diving into advanced diagnostics, check the fundamentals.
- Is the VM running? Look in the Azure Portal or use Azure CLI.
- Is the user connecting with the right credentials? Remote Desktop and SSH issues often come down to simple misconfigurations.
- Is the region or availability zone experiencing issues? Sometimes the problem isn’t your VM but Azure itself.
I once spent nearly an hour troubleshooting a “down” VM, only to discover the user was trying to connect to the wrong IP address. Lesson learned: always verify the basics first.
Step 2: Check Networking
Networking is the number one source of VM problems. A VM might be running perfectly but remain unreachable because of a firewall rule or misconfigured subnet.
What to look for:
- Network Security Groups (NSGs): Are inbound/outbound rules blocking traffic?
- Public IP settings: Does the VM actually have one assigned?
- DNS configuration: Misconfigured DNS can make services look offline when they’re not.
In one case, I resolved a production outage simply by correcting a misapplied NSG rule. The fix took two minutes, but identifying the issue required checking every network hop.
Step 3: Examine Performance Metrics
If the VM is accessible but slow, dig into performance data using Azure Monitor. Key metrics include:
- CPU utilization: Consistently high usage may mean you need to resize the VM.
- Memory pressure: Insufficient RAM can cause sluggish applications and timeouts.
- Disk IOPS and latency: Storage bottlenecks often show up here.
I once had a database server that users swore was “broken.” The metrics told a different story: it was under-provisioned. Moving from a D-series to an E-series VM solved the performance issue without touching the database itself.
Step 4: Review Boot and System Logs
For VMs that won’t start or keep failing during boot:
- Boot diagnostics: Review screenshots and logs from the Azure Portal.
- Serial console access: Useful for diagnosing OS-level boot issues.
- Event logs (Windows) or syslog (Linux): Check for driver errors, corrupted files, or failed services.
One Windows VM I worked on refused to boot after a patch cycle. Using the serial console, I traced it to a bad driver update. Rolling back the driver got the VM running again without needing a full rebuild.
Step 5: Validate Storage and Disks
Storage issues can cause corruption or prevent VMs from starting. Verify that:
- The OS disk is healthy and attached.
- Data disks are mounted and accessible.
- Snapshots or backups are available for recovery if needed.
I once restored a critical VM by attaching its OS disk to a healthy VM, copying the data, and creating a new instance. Without disk-level knowledge, that recovery would have taken much longer.
Step 6: Use Azure Diagnostics and Tools
Azure provides powerful troubleshooting tools:
- Azure Resource Health: Tells you if the issue is with the VM or Azure’s infrastructure.
- Log Analytics: Lets you run queries across VM logs for deeper analysis.
- Azure Advisor: Provides recommendations on performance and reliability.
These tools not only speed up troubleshooting but also help document what happened — something recruiters and hiring managers value when they hear about your structured approach to solving problems.
Best Practices I’ve Learned
- Always check the simple things first — it saves time and embarrassment.
- Document recurring fixes. Many issues repeat, and having a playbook helps.
- Use monitoring proactively to spot problems before users report them.
- Combine metrics with user feedback; numbers tell part of the story, but users often highlight the real impact.
- Keep backups and snapshots ready. Sometimes the quickest fix is a restore.
Why Recruiters Care
Troubleshooting may not sound glamorous, but it’s where administrators prove their worth. In an interview, saying “I fixed an NSG misconfiguration that restored access for 200 users in minutes” or “I diagnosed storage latency that was slowing down a database server and solved it by resizing the VM” shows practical, results-driven experience.
Recruiters look for candidates who can stay calm, follow a process, and get systems back online quickly. Highlighting your troubleshooting skills shows you’re not just maintaining infrastructure — you’re solving business-critical problems under pressure.
Conclusion
Azure VMs are powerful, but like any system, they sometimes fail. Knowing how to troubleshoot them effectively is a core skill for any administrator. From verifying connectivity to digging into logs and performance metrics, a structured approach ensures faster resolutions and happier users.
For administrators, these skills reduce downtime and keep environments stable. For recruiters, they demonstrate the ability to handle pressure, adapt to complex environments, and deliver value where it matters most.