Azure Monitor, Explained Honestly
Azure Monitor is the observability layer Microsoft builds into Azure — metrics, logs, application traces, and alerting for everything with an Azure resource ID. If your estate lives in Azure, it's the sensible default. The interesting questions start where your estate doesn't.
The Pieces of Azure Monitor
Metrics & logs
Platform metrics from every Azure resource; logs into Log Analytics (KQL).
Application Insights
APM for your applications: traces, dependencies, failures.
Alerts & actions
Threshold and query alerts wired to action groups.
Arc extension
Agents bring on-prem OS metrics into the same workspace.
Where Azure Monitor Stops
Two boundaries matter in practice. Cost: ingestion-based pricing rewards discipline and punishes verbosity — log everything and Log Analytics becomes a budget conversation. Scope: for hybrid estates, Arc agents see your on-prem servers only from the OS up. The hardware underneath — BMC health, failing PSUs and disks, rack power and thermals, the facility itself — has no Azure resource ID and never appears. Hybrid teams typically run Azure Monitor for the cloud half and an infrastructure platform like Sensaka for the physical half, with events forwarded so one pane still exists.
Common Questions
What is Azure Monitor?
Azure Monitor is Microsoft's built-in observability service for Azure: it collects metrics and logs from Azure resources, VMs, and applications, with Log Analytics for queries, Application Insights for APM, and alerting on top.
What does Azure Monitor cost?
Pricing is consumption-based, driven mostly by log ingestion and retention (per GB). Costs are famously easy to underestimate — verbose logging on a busy estate can make Log Analytics one of the larger line items on an Azure bill.
Can Azure Monitor watch on-premises infrastructure?
Partially. Azure Arc and agents extend it to on-prem servers at the OS level. What it can't see is the physical layer — server hardware health below the OS, racks, power, cooling — which needs infrastructure-native tooling.
What are the alternatives to Azure Monitor?
For Azure-native monitoring it's the default. Teams complement it with Grafana for dashboards, Datadog or Dynatrace for multi-cloud APM, and platforms like Sensaka for the physical and hybrid infrastructure Azure Monitor doesn't reach.