Azure Diagnostics

> AUTHORITATIVE GUIDANCE — MANDATORY COMPLIANCE > > This document is the official source for debugging and troubleshooting Azure production issues. Follow these instructions to diagnose and resolve common Azure service problems systematically.

Triggers

Activate this skill when user wants to:

• Debug or troubleshoot production issues
• Diagnose errors in Azure services
• Analyze application logs or metrics
• Fix image pull, cold start, or health probe issues
• Investigate why Azure resources are failing
• Find root cause of application errors
• Troubleshoot App Service issues (high CPU, deployment failures, crashes, slow responses, TLS/custom domains)
• Respond to prompts like "troubleshoot app service", "app service high CPU", or "app service deployment failure"
• Troubleshoot Azure Function Apps (invocation failures, timeouts, binding errors)
• Find the App Insights or Log Analytics workspace linked to a Function App
• Troubleshoot AKS clusters, nodes, pods, ingress, or Kubernetes networking issues
• Troubleshoot Azure VM connectivity issues (RDP/SSH failures, port 3389/22 timeouts, NSG or firewall blocking, credential resets)
• Troubleshoot Azure Messaging SDK issues (Event Hubs, Service Bus connection failures, AMQP errors, message lock issues)

Rules

1. Start with systematic diagnosis flow
2. Use AppLens (MCP) for AI-powered diagnostics when available
3. Check resource health before deep-diving into logs
4. Select appropriate troubleshooting guide based on service type
5. Document findings and attempted remediation steps
6. Route AKS incidents to the dedicated AKS troubleshooting document

Quick Diagnosis Flow

1. Identify symptoms - What's failing?
2. Check resource health - Is Azure healthy?
3. Review logs - What do logs show?
4. Analyze metrics - Performance patterns?
5. Investigate recent changes - What changed?

Troubleshooting Guides by Service

| Service | Common Issues | Reference | |---------|---------------|-----------| | Container Apps | Image pull failures, cold starts, health probes, port mismatches | container-apps/ | | App Service | High CPU, deployment failures, crashes, slow responses, TLS/custom domains | app-service/ | | Function Apps | App details, invocation failures, timeouts, binding errors, cold starts, missing app settings | functions/ | | AKS | Cluster access, nodes, kube-system, scheduling, crash loops, ingress, DNS, upgrades | AKS Troubleshooting | | Compute | VM RDP/SSH connectivity, NSG/firewall blocks, credential resets, VM agent/tooling issues | VM Connectivity Troubleshooting | | Messaging | Event Hubs & Service Bus SDK errors, AMQP failures, message lock, connectivity | Messaging Troubleshooting |

Routing

• Keep Container Apps and Function Apps diagnostics in this parent skill.
• Route active AKS incidents, AKS-specific intake, evidence gathering, and remediation guidance to AKS Troubleshooting.
• Route Azure VM RDP/SSH connectivity, NSG/firewall, credential reset, and VM agent troubleshooting to VM Connectivity Troubleshooting.
• Route Azure Messaging SDK troubleshooting (Event Hubs, Service Bus) to Messaging Troubleshooting.

Quick Reference

Common Diagnostic Commands

bash
# Check resource health
az resource show --ids RESOURCE_ID
# View activity log
az monitor activity-log list -g RG --max-events 20
# Container Apps logs
az containerapp logs show --name APP -g RG --follow
# Function App logs (query App Insights traces)
az monitor app-insights query --apps APP-INSIGHTS -g RG \
  --analytics-query "traces | where timestamp > ago(1h) | order by timestamp desc | take 50"

AppLens (MCP Tools)

For AI-powered diagnostics, use:

mcp_azure_mcp_applens
  intent: "diagnose issues with <resource-name>"
  command: "diagnose"
  parameters:
    resourceId: "<resource-id>"

Provides:
- Automated issue detection
- Root cause analysis
- Remediation recommendations

Azure Monitor (MCP Tools)

For querying logs and metrics:

mcp_azure_mcp_monitor
  intent: "query logs for <resource-name>"
  command: "logs_query"
  parameters:
    workspaceId: "<workspace-id>"
    query: "<KQL-query>"

See kql-queries.md for common diagnostic queries.

Check Azure Resource Health

Using MCP

mcp_azure_mcp_resourcehealth
  intent: "check health status of <resource-name>"
  command: "get"
  parameters:
    resourceId: "<resource-id>"

Using CLI

bash
# Check specific resource health
az resource show --ids RESOURCE_ID

# Check recent activity
az monitor activity-log list -g RG --max-events 20

References

• KQL Query Library
• Azure Resource Graph Queries
• App Service Troubleshooting
• Function Apps Troubleshooting
• VM Connectivity Troubleshooting
• Messaging Troubleshooting