README.md

Frequent questions - need to memorize

This section contains random important topics for easier access.

Mindmaps

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• Networking Overview

Differences between Availability Set and Availability Zone

Availability Set	Availability Zone
Protect from Hardware failures within data centers	Protect from entire data center failure
SLA 99.95 %	SLA 99.99%

Availability Set

• No additional cost
• Same data center
• At least 2 VMs in set

Availability Zone

• 3 per region (not all regions supported)
• Separate power source, network and cooling

Characteristics of different redundancy options

Redundancy Options Scenarios

Scenario	LRS	ZRS	GRS/RA-GRS	GZRS/RA-GZRS (preview)
Node unavailability within a data center	Yes	Yes	Yes	Yes
An entire data center (zonal or non-zonal) becomes unavailable	No	Yes	Yes	Yes
A region-wide outage	No	No	Yes	Yes
Read access to your data (in a remote, geo-replicated region) in the event of region-wide unavailability	No	No	Yes (with RA-GRS)	Yes (with RA-GZRS)
Designed to provide __ durability of objects over a given year	at least 99.999999999% (11 9's)	at least 99.9999999999% (12 9's)	at least 99.99999999999999% (16 9's)	at least 99.99999999999999% (16 9's)
Supported storage account types	GPv2, GPv1, Blob	GPv2	GPv2, GPv1, Blob	GPv2
Availability SLA for read requests	At least 99.9% (99% for cool access tier)	At least 99.9% (99% for cool access tier)	At least 99.9% (99% for cool access tier) for GRSAt least 99.99% (99.9% for cool access tier) for RA-GRS	At least 99.9% (99% for cool access tier) for GZRSAt least 99.99% (99.9% for cool access tier) for RA-GZRS
Availability SLA for write requests	At least 99.9% (99% for cool access tier)	At least 99.9% (99% for cool access tier)	At least 99.9% (99% for cool access tier)	At least 99.9% (99% for cool access tier)

Redundancy Options Simple

locally redundant storage	Designed to provide at least 99.999999999% (11 9’s) durability of objects over a given year by keeping multiple copies of your data in one data centre.
zone redundant storage	Designed to provide at least 99.9999999999% (12 9’s) durability of objects over a given year by keeping multiple copies of your data across multiple data centres or across regions.
geographically redundant storage	Designed to provide at least 99.99999999999999% (16 9’s) durability of objects over a given year by keeping multiple copies of the data in one region, and asynchronously replicating to a second region.
read-access geographically redundant storage	Designed for to provide at least 99.99999999999999% (16 9’s) durability of objects over a given year and 99.99% read availability by allowing read access from the second region used for GRS.

How to choose compute option

Differences between load balancers

Service	Global/regional	Recommended traffic
Azure Front Door	Global	HTTP(S)
Traffic Manager	Global	non-HTTP(S)
Application Gateway	Regional	HTTP(S)
Azure Load Balancer	Regional	non-HTTP(S)

Understand SKUs for App Service Plans

Monitoring and logging

	Azure Diagnostic Extension	Log Analytics agent	Dependency agent
Environments supported	Azure	AzureOther cloudOn-premises	AzureOther cloudOn-premises
Operating systems	WindowsLinux	WindowsLinux	WindowsLinux
Agent dependencies	None	None	Requires Log Analytics agent
Data collected	Event LogsETW eventsSyslogPerformanceIIS logs.NET app tracing output logsCrash dumps	Event LogsSyslogPerformanceIIS logsCustom logsData from solutions	Process details and dependenciesNetwork connection metrics
Data sent to	Azure StorageAzure Monitor MetricsEvent Hub	Azure Monitor Logs	Azure Monitor Logs

Log Analytics Agent

Log Diagnostics Agent

Data Source	Description
Performance counter metrics	Operating System and custom performance counters
Application logs	Trace messages written by your application
Windows Event logs	Information sent to the Windows event logging system
.NET EventSource logs	Code writing events using the .NET EventSource class
IIS Logs	Information about IIS web sites
Manifest based ETW logs	Event Tracing for Windows events generated by any process.(1)
Crash dumps (logs)	Information about the state of the process if an application crashes
Custom error logs	Logs created by your application or service
Azure Diagnostic infrastructure logs	Information about Azure Diagnostics itself