Azure Services and Concepts
This is another notes dump. I'm working through a Pluralsight course called Microsoft Azure Fundamentals (AZ-900). These are some of my notes from doing this course.
Don't Rely on this to Learn
I don't recommend you read the notes. They might lure prospective future employers to my sight and I might look back and read them, but they're not really there for people to learn from. However, Pluralsight is there for people to learn from. Because they're not intended to be a source of learning they won't be written to cater to learners. I will miss whole chunks of information, where I already knew that and I might drop whole sections if I feel it's not relevant knowledge for my future career.
I tend to prefer to study things that aren't bound to a specific technology or company, so I will avoid too much time being spent on this, so I can free up time to focus on other things. This is one of the major reasons for this Azure related gap in my knowledge. I would rather learn to make applications than use them and Azure provides a number of Microsoft-bound services. Also, since as I am a student, I am prone to misunderstanding and my notes might reflect a misunderstanding or out-of-date information.
Instead of reading this course pop over to Pluralsight for a small subscription fee, you can see the content of this spread out among a number of videos with multimedia. It will be quicker to learn from than this. For developers and sys-admins who tend to earn £20k+, they should be affordable at £24 per month and if someone is not a developer or a sys-admin, then this course is probably a bit beyond them at this stage.
AZ900 Content
This is about the specific products provided by Azure, which can be used in making a solution. Some things covered will be concepts like data centres, regions, ARM, Azure CLI, ARM Templates, Azure virtual network gateways, storage accounts, platform solutions like IoT, AI and big data solutions. This should cover the concepts portions of the AZ900 exam.
Sources for these notes
The majority of this is taken from Neil Morressy's course on Pluralsight. This will reflect notes taken during a video so they might be a bit spacial. Grammar will go out the window, while I'm trying to keep up so good luck if you're still reading. I'm also going to insert Vlad Catrinescu's course content.
What is Cloud?
What is a Cloud? How does it help us? For a lot of people cloud just means online. The author Mr Catrinescu seems to suggest EVERY organisation out there is using Cloud computing... I don't think this is true. I mean I tend to avoid absolutes like everything, but I know in my own limited company we use cloud and in my other employer, we provide a Cloud-based solution so there's two that do use it. But some organisations like to avoid computers altogether, builders or wholesalers the odd company here or there. But I think any website is most likely going to be hosted on some sort of Cloud solution.
Once upon a time, we had dedicated servers for everything. Each networked application installed was often required to run on a dedicated server to ensure quality through dedicated processing power. Each one had its own CPU, RAM etc. Organisations were spending a ton of money on servers which mostly sat there unused. I mean not all applications are used all the time and yet they need dedicated server space.
We introduced virtual machines so something could have dedicated processing and more but on less architecture... there are still some more costs and there's plenty of hardware requirements. This is more cost effective than before but there is space for improvement.
Cloud allows for a companies to pay for Saas without worrying about hardware maintenance, secure server rooms, and more. The cloud provider makes sure there are enough shared resources to provide the solution. The provisioning of new VMs and more is done for the user and provided in an almost instant manner. Services can be billed by their running time so you're not paying for services when you're not using them.
CAPEX and OPEX
Capex (capital expenditures) involve buying and setting things up which are going to be used for many years. Their costs can't be deducted in the year it was spent some of it needs to be carried over into the future years.
Opex on the otherhand (operating expenditures) are deducted in the year they were used.
Why Use Cloud?
You can pay based on how many hours a virtual machine is up for you. You can set it to go up based on metrics for example if the cpu was at 70%. This is autoscale.
Cloud providers safeguard against loss or hardware failure. They can have services in other countries where they might not be affecgted by the same natural disaster for example. These provide redundancy.
Why Use Azure?
Azure is the most important cloud provider to use since it is the most used and it is used by 85% of the FTSE 500 companies.
X As A Service
We will be covering Iaas, Saas and Paas (Infrastructure as a service, Software aas and Platform aas). The main difference between these Services i the amount which is provided and who manages what.
With your typical On-premises servers you need to manage everything. With Iaas (Infrastructure as a Service) the hardware is set up by Microsoft or the Cloud provider while the software is entirely managed by the user.
With Paas the entire platform including things like the runtime, Operating system, any middleware, SQL server IIS are all managed by the provider and only the Application / Data is managed by the user.
Eventually we look at a Saas solution. This is where you are licensed access to a piece of software like Office365 where the management of the application is entirely provided by the supplier.
Catrinescu gives a good example of this using pizza. Check out his course on pluralsight.
I like to think of it as running a screening of a movie. Do it yourself, is where you hold the screening at home, and show the movie using your TV and DVD player etc. Infrastructure as a service is a bit like if you rent the room to run a screening but bring everything like the projector, DVD player and movie, Platform as a service is a bit like renting a room at the cinema, they provide nearly everything but you bring the movie. Finally, Software as a Service is like buying tickets for the cinema.
Deployment Models
Private and Public Cloud
There are two main strategies. Public Cloud and Private Cloud. If I were to guess on what Private Cloud means I would guess correctly, that in this circumstance the rented infrastructure is private to the organisation that commissioned it and not shared with other people.
With the other type the public cloud then some of the hardware can be shared between different cloud clients so the same hardware is being used by multiple people. This means you can save money especially while the application is remaining dormant.
Hybrid Cloud
A third-type enters the arena called the Hybrid which is essentially a mixture of the two with Orchestration and Automation between the two.
Community Cloud
The final type is essentially in my opinion a shared private cloud, it is called a "Community cloud". This is where a cloud is used across an entire community of organisations, but not accessible to people outside of that community. This can be like a cloud used for government bodies, but not outside government bodies. Often when all the organisations on the cloud are from the same industry or community there are similar security concerns, data protection requirements and legal requirements which makes this really suitable to join resources.
Most Microsoft's solutions are public cloud. Microsoft also has options for private and hybrid cloud solutions.
Azure stack connected scenarios - Hybrid
Azure stack disconnected scenarios - Private
Azure Government - Azure offerring specific to government bodies including FedRAMP, DOD, CJIS
Other Cloud Community offerings are Azure China and Azure Germany with specific requirements set to the needs to these particular countries. I assume Azure China is specific to China's needs which require that the Azure be isolated from the world-wide internet and Germany has some Data Protection Laws that are very strict and specific.
Data Centres
Neil Morrissey in his course available on Pluralsight comments about Data Centres. A data centre is essentially a building which just hosts lots of infrastructure for providing cloud services. Naturally for security reasons they don't publish the address of their datacentres.
Many of them include what's called ITPACs which stands for IT PreAssembled Components. This is essentially a stack of servers and hardware with its own power supplies and coolant system. Microsoft also experimented with shipping containers of ITPACs so they could easily bring a whole one back online when one goes down but that model is being replaced now.
A datacentre generally complies with various security protocols such as FedRAMP, ISO 27001, HIPAA, SOC 1 and 2.
To enable separation, data is encrypted and kept separate from other customers. It is also stored 3 times over in each data centre for redundancy and you can also permit your data to be stored in multiple data centres for additional recovery.
These data centres consume a lot of power, but Microsoft is carbon neutral since 2012 and aims to be 100% renewable energy by 2025.
Data Regions
When you set up most services with Azure there is an option to choose where the data is stored. In the form of a "Location". This is an area where there are a collection of Data Centres and this allows for you to choose a country and area of the country relatively close to your customers or in a place where specific laws operate. You can specify a region like UK South, Central United States, Japan West, Korea South, etc.
Some services are global and you don't specify a region such as Azure Active Directory.
Not all azure services are available in all regions. If you want to see what is available where you can go to https://azure.microsoft.com/en-gb/global-infrastructure/services/ which will allow you to filter services offered by Azure and see what regions they are available in. Also certain VMs with certain levels of processing power might be restricted to certain regions or have different prices for different regions.
For example here I filtered for Genomics and found it's not available in Canada for Central US regions.
Any service where the "Non-regional" column is ticked are the ones where you are not required to pick a column as they are global services.
For more information on this, I recommend Neil Morrissey's course on Pluralsight which is part of the Azure fundamentals AZ-900 path learning. This covers all basic concepts and information, which are relevant to Azure.
Azure Geography
This is an area that might include one or more regions. Often an entire Geography is subject to similar laws about data residency so they should mostly be entire countries where the law is the same.
Microsoft might copy data to other data regions other than the one you have selected for redundancy purposes but they would not copy it outside the Geography. This is particularly the case when you select something like Geo-redundant storage.
Region pairs
This pair is often two twinned regions, which are located over 300+ miles apart based in a single geography. They are so far apart because it allows for large redundancy against large scale issues for example Texas going without power a few months ago. If there was another data centre in a region just the other side of the state it too might be without power suffering in the strange snow-storm, which was probably caused by climate change. (Side note: Climate change is real yo! Companies didn't want their climate damaging effects challenged, so it was cheaper to brainwash most of the US and whole pockets of the internet than actually investing in renewable energy so they released a ton of false propaganda to suggest Climate Change wasn't real. It was real ask any scientist who works in the field and isn't on an Oil company's payroll).
When you select "Geo-redundant" storage then Microsoft automatically copies your data across to the other region in the Region Pair. When a disaster affects both Regions in a region pair one of the two pairs is prioritised.
Availability Zones
An availability zone is within a single Azure Region and may contain multiple data centres. Some regions just contain one data centre, but some contain 3 or more availability zones. You can organise zone redundant storage to replicate your data across different data centres in the region, but that data won't be replicated across multiple Azure Regions, it will just remain in one Azure Region within one Azure Geography.
This is all explained thoroughly in Neil Morrissey's course on Microsoft Azure's Services and Concepts available via PluralSight. This April I think Pluralsight is doing an offer for them. I am not paid to recommend them, I'm just finding the courses available really useful and trying to step up my knowledge speedily and consistently with what's required for my job.
Resource Groups
Information to follow.
Graeme