Networking Flashcards
What is a VNET?
Virtual Network. used to provide private connectivity between VMs and other Azure services
By default can the outside world access a VNET?
No
What 3 things do you need to specify in order to set-up a VNET?
Subnet, Address Spaces, Security
What must you ensure if one VNET needs to connect to another VNET?
Ensure the address spaces do not overlap
What are NSGs and what do they provde?
Network Security Group. Allows control over traffic flow to and from subnets and VMs
What do NSGs act as?
Software Firewalls i.e. apply custom rules at each inbound and outbound request
What is a VHD?
Virtual Hard Drive
What’s the difference between Availability Zones and Availability Sets?
Availability Sets are VMs within the same zone (one or more datacenters). Availability Zones are VMs spanning multiple zones (two or more datacenters spanning multiple zones)
What does CIDR stand for?
Classless inter-domain routing
Given 192.168.1.1, what’s the CIDR notation for masking the A-Block?
192.168.1.1/8. Range 192.0.0.0 - 192.255.255.255. Subnet mask 255.0.0.0
Given 192.168.1.1, what’s the CIDR notation for masking the B-Block?
192.168.1.1/16. Range 192.168.0.0 - 192.168.255.255. Subnet mask 255.255.0.0
Given 192.168.1.1, what’s the CIDR notation for masking the C-Block?
192.168.1.1/2. Range 192.168.1.0 - 192.168.1255. Subnet mask 255.255.255.0
When creating a VNET, what are Service Endpoints?
Pre-built configuration to allow other Azure Services and Resources to access the VNET
When creating a subnet, how many addresses does Azure reserve by default?
5
How can you enable public access to VMs, Load Balancers, and Gateways?
Create a ‘Public IP Address’ resource and assign it to a VM or Load Balancer or Gateway
What is an ASG?
Application Security Group
What is an ASG used for?
Reduces the number of NSGs and security rules you require. It groups the resources that require the SAME rules together. So no need to create an NSG for EVERY SUBNET
In production, what SKU of load Balancer is recommended BASIC or STANDARD?
Standard. Enables you to scale your applications and create high availability for small scale deployments to large and complex multi-zone architectures
How does a Load Balancer Health Probe work?
It pings the VM periodically. If it doesn’t report back in time after ‘X’ attempts, then it marks it as ‘unhealthy’ until it’s fixed
In Load Balancers, what is a ‘Back-end Port’?
It’s a port not exposed publicly but used by the back-end application. So traffic coming in from port 80/443 can be mapped to the back-end port of the application e.g. 8080
How many VM Sets can you Load Balance on the BASIC SKU?
1
How many VM Sets can you Load Balance on the STANDARD SKU?
Many
Can you auto-scale application gateways?
Yes and can scale to different availability zones
What is FQDN an acronym of?
Fully Qualified Domain Name
What 4 back-end pools can Application Gateways be pointed to?
VMs, App Services, VMSS, IP Address/FQDN
What is Azure Front Door?
It combines the best of Load Balancers and Application Gateways but instead of being REGIONAL it’s GLOBAL
What 3 things do you need to create an Azure Front Door?
Front-end hosts, Back-end pools, and Routing Rules
What is Point-to-Point VPN?
Where individual VPN client connects to the VNET Gateway on Azure
What is Site-to-Site VPN?
Where all on-premisis machines are connected to the Azure VNET Gateway
What is Virtual WAN?
This is where you can connect 2 offices together using Azure
