Describe Azure Compute and Networking Services Flashcards
1
Q
What is Azure VM?
A
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
2
Q
When are VMs an ideal choice?
A
- you need to take control over OS
- you need ability to run custom software
- you need to use customer hosting configs
3
Q
What are VM images?
A
- 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
4
Q
What are VM scale sets?
A
- 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
5
Q
What are VM availbility sets?
A
- 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
6
Q
What is an update domain?
A
- 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
7
Q
What is a fault domain?
A
- 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
8
Q
Common VM examples?
A
- Testing and development
- Running apps in cloud
- extending datacenter to the cloud
- disaster recover
9
Q
How do VMs help with lift and shift?
A
- You can create an image of a physical server and host it within a VM with little or no changes
10
Q
What resources are required for VMs?
A
- compute size; number of cores and amount of RAM
- storage; HDD, SSD etc
- networking; virtual network, public IP and port config
11
Q
What is azure virtual desktop?
A
- 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
12
Q
how does azure virtual desktop enchance security?
A
- 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`
13
Q
What are containers?
A
- 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
14
Q
What are container instances?
A
- Paas offering to allow you to upload your containers and run them for you
15
Q
When would we chose VMs over containers and vise versa?
A
- Choose VMs when you want complete control
- Choose containers when portability and performance are more of a concern
16
Q
When are containers used?
A
- 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
17
Q
What are azure functions?
A
- 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
18
Q
benefits of azure functions?
A
- 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
19
Q
What is Azure App Service?
A
- 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
20
Q
Types of app service?
A
- 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
21
Q
What are azure virtual networks?
A
- 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
22
Q
What do azure virtual networks provide?
A
- isolation and segmentation
- internet comms
- comms between azure resources
- comms with on prem resources
- route network traffic
- filter network traffic
- connect virtual networks
23
Q
How do azure virtual networks support endpoints?
A
- 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
24
Q
What is isolation and segmentation in terms of azure virtual network?
A
- 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
25
Q
How can you enable internet communicated on azure virtual network?
A
assigning a resource to a public IP address or putting the resource behind a public load-balancer
26
Q
What is virtual network peering?
A
- allows two virtual networks to connect directly to each other meaning they can be linked together
- network traffic between peered networks is private and travels on Microsoft backbone, never entering the public internet
- enables resources in each virtual network to communicate with each other even in separate regions
- globe of interconnected networks can be created
- User Defined routes allow you to control the routing tables between subnets within or between virtual networks allowing for greater control of traffic
27
Q
What does the Azure VPN gateway enable?
A
Gateway instances are deployed in dedicated subnet of the virtual network enabling;
- connection of on-prem datacenters to virtual networks through site-site
-connection of devices to VNs through point-site
-connection of VNs to other VNs through network-network
28
Q
What are the benefits of Azure VPN gateway?
A
- all data transfer is encrypted
- you can deploy one gateway in each virtual network and then use one gateway to connect to multiple locations
29
Q
What is a policy-based VPN gateway?
A
- specify statically the IP address of packets that should be encrypted through each tunnel
- evaluates every data packet against those sets of addresses to choose the tunnel where that packet is sent through
30
Q
What is a Route-based VPN gateway?
A
- IPSec tunnels are modeled as a network interface or virtual tunnel interface
- IP routing decides which one of these tunnel interfaces to use when sending each packet
- preferred connection method for on-prem devices
- most resilient to topology changes such as the creation of new subnets
- used for point-site, multiple connections and connections between VNs
31
Q
What is Azure express route?
A
- lets you extend your on-prem networks into the Microsoft cloud over a private connection, with the help of a connectivity provider
- You can establish connections to services such as Azure and 365 allowing you to connect offices and datacenters to these services
- the connection is called an ExpressRoute circuit
- connection can be from wired or wireless network
- don’t go over public internet allowing for more reliability, faster speeds, consistent latencies and higher security
32
Q
Benefits of ExpressRoute?
A
- connectivity to Microsoft cloud services across all regions in the geopolitical region. You could use ER to connect two circuits across the globe without using public internet
- local connectivity to MS across all regions with the ExpressRoute global reach
- dynamic routing between your next work and Microsoft
- build in redundancy
33
Q
What are the four express route connectivity models?
A
- cloudExchange colocation
- point-point ethernet connection
- any-any connection
- directly from ExpressRoute sites
34
Q
What is Azure DNS?
A
- Hosting service for DNS comains that provides name resolution by using Azure infrastructure
- you manage DNS records using same creds, APIs, tools and billing as your other azure services
35
Q
Benefits of Azure DNS?
A
- Reliability and performance; azures global network of DNS servers provides resiliency and high availability
- Security; based on Azure Resource Manager which provides role based access control, activity logs and resource locking
- Ease of use; can manage it directly in Azure
- Cusomtizable virtual networks with private domains
- Alias records
