Describe Azure Compute and Networking Services Flashcards
What is Azure VM?
allows you to create VMs in the cloud which provide IaaS in the form of virtualised servers that can be used in many ways
- You can customise all software running on a Vm
- flexibility of virtualisation without having to buy hardware, but still IaaS so need to configure, update and maintain software that runs on VM
When are VMs an ideal choice?
- you need to take control over OS
- you need ability to run custom software
- you need to use customer hosting configs
What are VM images?
- allow you to create a VM in minuets
- template used to create a VM and may already include OS and other software like dev tools or web hosting environments
What are VM scale sets?
- let you create and manage a group of identical, load-balanced, VMs
- azure automates the creation and allows you to centrally manage, configure and update a large number of VMs in mins
- number of VMs can scale up and down to respond to demand
- also use load balancing to ensure resources used efficiently
- you can build large-scle services for areas such as compute and big data
What are VM availbility sets?
- Designed to ensure that VMs stagger updates and have varied power and network connectivity preventing losing all VMs with a single failure
-They manage this by grouping VMs into update and fault domains - No additional cost
What is an update domain?
- groups Vms that can be rebooted at the same time allowing you to apply updates while knowing that only one update domain grouping will be offline at a time
- given 30 min recover time before next update domain starts
What is a fault domain?
- groups VMs by common power source and network switch
- by default avability sets will be split VMs into three fault domains
- protects against physical power or networking failure
Common VM examples?
- Testing and development
- Running apps in cloud
- extending datacenter to the cloud
- disaster recover
How do VMs help with lift and shift?
- You can create an image of a physical server and host it within a VM with little or no changes
What resources are required for VMs?
- compute size; number of cores and amount of RAM
- storage; HDD, SSD etc
- networking; virtual network, public IP and port config
What is azure virtual desktop?
- desktop and application virtualisation service that runs on the cloud
- allows you to use a cloud-hosted version of windows from anywhere
- cross-platform
- and works with apps you can use to access RDP or most modern browsers
how does azure virtual desktop enchance security?
- provides centralized security management for users’ desktops with AD
- you can enable MFA to secure sign-ins
- you can also secure access to data with role-based access controls
- data and apps are separate from local hardware meaning the risk of confidential info being left on personal devices is reduced`
What are containers?
- virtualization environment that bundles a single app and dependancies
- you can run multiple containers on a single physical or VM host each with a different OS, unlike VMs that are limited to one OS
- you don’t manage OS and instead they are lightweight resources that are designed to be created, scaled out and stopped dynamically
- you can scale out VMs but containers offer a lighter more agile solution
- quick restart if there is a crash or hardware interruption
- e.g. docker
- VMs virtualize hardware, containers virtualize OS
What are container instances?
- Paas offering to allow you to upload your containers and run them for you
When would we chose VMs over containers and vise versa?
- Choose VMs when you want complete control
- Choose containers when portability and performance are more of a concern
When are containers used?
- used to create solutions using microservice architecture
- break solutions into smaller, independent pieces
- e.g. split a website into a container hosting the front end, another hosting back end and another for storage
- allows you to separate app into logical divisions that can be maintained, scaled or updated independently
What are azure functions?
- event-driven, serverless compute option that doesnt require maintaining VMs or containers
- event wakes the function, alleviating need to keep resources provisioned when there are no events
benefits of azure functions?
- ideal when only concerned about the code running the service and not about the platform of infrastructure
- can be triggered by timer or message from another azure service and used when work can be completed within seconds or less
- auto-scale on demand
- deallocates resources when the function finished
- stateless (behave as if restarted every time) or stateful (passed context describing prior activity)
- allow for serverless computing
What is Azure App Service?
- allows you to build and host web apps, mobile back-ends and APIs in multiple programming language without managing infrastructure
- auto scaling + high availability
- windows and linux
- auto deployment from GitHub, Azure DevOps or any Git repo
- lets you focus on building and maintaining the app while azure focuses on keeping environment up and running
- ideal choice to host web apps
Types of app service?
- Web apps; includes full support for hosting web apps
- API apps; you can build REST-based web APIs by using your choice of language and framework and get full Swagger support plus ability to publish API in Azure Marketplace
- WebJobs; run a program or script in the same context as a web, API or mobile app and can be scheduled or run by a trigger
-Mobile apps; store mobile app data in cloud SQL, auth customers using social sign in, send push notications and execute custom back-end logic
What are azure virtual networks?
- enable resources such as VMs, web apps and DBs to communicate with one another and with users on the internet or with on-premises client computers
What do azure virtual networks provide?
- isolation and segmentation
- internet comms
- comms between azure resources
- comms with on prem resources
- route network traffic
- filter network traffic
- connect virtual networks
How do azure virtual networks support endpoints?
- support public and private endpoints to enable comms between external or internal resources with other internal resources
- public endpoints have public IP that can be accessed from anywhere in world
- private exist within a virtual network and have a private IP from within the address space of the network
What is isolation and segmentation in terms of azure virtual network?
- when you set up a network you define a private IP space by using either public or private IP range
- the range only exists within the virtual network and is not internet routable but can be divided into subnets
- you can configure the network to use internal or external DNS server