Windows Azure Diagnostics

Neil Mackenzie

Overview

• Motivation for Windows Azure Diagnostics• Architecture of WAD• Configuring WAD• Managing WAD• Demonstration

Why Windows Azure Diagnostics?

WAD Provides:• visibility into instance VMs• access to IIS logs, event logs and traces• configuration of diagnostic information captured • consistent way to persist diagnostic information

WAD Supports:• non-intrusive investigation of problems• auto-scaling through access to performance counters

IntelliTrace

WAD Architecture

Diagnostics Agent• Runs on each instance• Persists diagnostic data to Azure Storage

Configuration• Instance-specific WAD configuration• Located in an Azure Blob container• Polled by Diagnostics Agent

Azure Storage• WAD uses blobs, tables and queues

.NET API

Configuration

WAD Configuration• Instance-specific blobs in wad-control-container

WAD Configuration specifies:• data buffers to be captured• data buffers to be persisted• transfer schedule

WAD .NET API updates WAD configurationDiagnostics Agent:• polls WAD configuration to identify changes.• implements changes

Data Buffers

Data Buffer Azure Storage Location

Windows Azure logs * WADLogsTable

Windows Diagnostic infrastructure logs * WADDiagnosticsInfrastructureLogsTable

IIS 7.0 logs (webrole) * wad-iis-logfiles (blobs)

Failed Request logs (webrole) wad-iis-failedreqlogfiles (blobs)

Windows Event logs WADWindowsEventLogsTable

Performance counters WADPerformanceCountersTable

Crash dumps wad-crash-dumps (blobs)

Custom error logs Configurable (blobs)

* Captured by defaultWADDirectoriesTable contains one entity for each blob stored by WAD

WAD captures data to the data bufferWAD persists data to the Azure Storage location

Custom Logging

WAD supports custom loggingConfigure:• Capture directory in local storage• Persistence location in Azure Blob storage• Transfer schedule

Persistence

Scheduled Transfers• Routine transfers to persistent storage• Transfer period specific to a data buffer

On-Demand Transfers• Immediate need to persist data• Possibility of duplicate data in persistent storage

Cleanup• WAD does not cleanup persisted data• Should not delete the tables/containers

Managing WAD

Diagnostics Agent started automatically• Default configurationWAD managed on a per-instance basis• Use RoleInstanceDiagnosticManager• Get WAD configuration for instance• Modify WAD configuration• Set current WAD configuration for the instance

On-Demand Transfers

On-Demand transfers configured for:• Instance• Data buffer

Use RoleInstanceDiagnosticManager• Configure on-demand transfer• Request on-demand transfer

Cleanup on-demand transfer• Get completion message from WAD notification queue• End on-demand transfer

One on-demand transfer per data buffer

Tools

Cerebrata• Azure Diagnostics Manager

Microsoft• Systems Center Operations Manager – Windows

Azure Management Pack RC

Demo

Web role with two instances demonstrating various aspects of Windows Azure Diagnostics

Contact Information

• Neil Mackenzie• Twitter: @mknz• Blog: http://convective.wordpress.com/