MICROSOFT AZURE FUNDAMENTALS (AZ-900)

SLA Service Level Agreement (Credit if on account if not met).

Azure Active Directory 99.9% Availability.

Compound SLA. Web app 99.95% ==> SQL database 99.99%. Raw SLA multiply components 99.94%

Scaling Vertically

Scale up - more RAM

Scale down - less RAM

Scaling Horizontally

Scaling out - more machines

Scaling in - less machines

Ability to automate scalability

Ability to scaling extremely fast

FAULT TOLERANCE

Multiple components (power supplies, networks cards, RAID - surviving a partial failure

DISASTER RECOVERY - BUSINESS CONTINUITY

Restoring service after disaster

Cons of On-Premises Model

CAPITAL EXPENSE + interest.

Over a period of time lifecycle. Don't last long

No agility, if need more, will take time.

Money tied up for years.

Hardware outdated before ROI reached.

Pros of the Cloud Model

No Capex - Renting hardware

Opex OPERATIONAL EXPENSE

Billed month-to-month

Agile

Principle of economies of scale

Consumption-based model

Most common

Owned and operated by third-party

Shared hardware and infrastructure

Advantages

Lower cost

No maintenance

Near-unlimited scalability

High reliability

Resources dedicated to single organization

On-Premises or third-party

Advantages

Flexibility

Security

Compliance

Scalability

Best of both worlds

Combine on-premises with public clouds

Data and applications can move between

Cloud bursting

Advantages

Control

Flexibility

Easy migration