Azure VNets and hybrid networking Flashcards
Capabilities of Vnets
Communication with internet Communication between Az resources Communication between on premise resources Filtering network traffic Routing network traffic
All resources in a VNet can communicate outbound to the internet, by default - True/ False
True - All resources in a VNet can communicate outbound to the internet, by default
Communication between Azure resources - 3 Key Mechanisms
VNets,
VNet service endpoints and
VNet peering
How can an inbound internet connectivity be set up for a vnet?
You can communicate inbound to a resource by assigning a public IP address or a public Load Balancer.
You can connect your on-premises computers and networks to a virtual network using any of the following options: 3 options
Point-to-site virtual private network (VPN),
Site-to-site VPN,
Azure ExpressRoute.
You can filter network traffic between subnets using –
- NSGs
2. NVAs - network virtual appliances like firewalls, gateways, proxies, and Network Address Translation (NAT) services.
Azure routes traffic between subnets, connected virtual networks, on-premises networks, and the Internet, by default. To override the default routes that Azure creates you can implement -
Route tables or
Border gateway protocol (BGP)
Design considerations for Az Vnet
- Address space and subnets
- Naming Convention
- Regions and Subscriptions
- Availability Zones
Azure reserves ____ IP addresses within each subnet
5
A well-chosen name helps you quickly identify the –
- Resource’s type
- Associated workload
- Deployment environment
- Azure region
There are four levels you can specify a scope:
Management group,
Subscription,
Resource group, and
Resource.
Scopes are _____, with each level of ______making the scope more specific.
hierarchical; hierarchy
Two subnets, within different virtual networks, can have same name - True/ False
True - Subnets are scoped to Virtual Networks
A resource can be created in a virtual network that exists in the _____ region and subscription as the resource - same/ different
same
Azure Availability Zone
- Azure Availability Zone enables you to define unique physical locations within a region.
- Each zone is made up of one or more datacenters equipped with independent power, cooling, and networking.
- Designed to ensure high-availability of your Azure services, the physical separation of Availability Zones within a region protects applications and data from datacenter failures.
You can add address spaces after creating the virtual network - True/ False
True
A public IP address
- Enables Internet resources to communicate with Azure resources
- Enables Azure resources to communicate outbound with Internet
- Enables Azure resources to communicate with other public-facing Azure services
A public IP address in Azure is not dedicated to a specific resource, until it’s assigned by a network engineer - True/ False
False - A public IP address in Azure is dedicated to a specific resource, until it’s unassigned by a network engineer
A resource without a public IP assigned can communicate outbound through –
network address translation(NAT) services, where Azure dynamically assigns an available IP address that isn’t dedicated to the resource.
Public resources like web servers must be accessible from the internet. You want to ensure that you plan ______that support these requirements.
Public IP addresses
Default outbound IP access for Azure VM
Azure provides an default outbound access IP for Azure Virtual Machines which aren’t assigned a public IP address, or are in the backend pool of an internal Basic Azure Load Balancer. The default outbound access IP mechanism provides an outbound IP address that isn’t configurable.
The default outbound access IP is disabled –
- When a public IP address is assigned to the virtual machine
- When the virtual machine is placed in the backend pool of a Standard Load Balancer with or without outbound rules
- If a Azure Virtual Network NAT gateway resource is assigned to the subnet of the virtual machine
Some of the resources you can associate a public IP address resource with:
- Virtual machine network interfaces
- Internet-facing load balancers
- VPN gateways
- Application gateways
- Azure Firewall
The default ip address allocation method is_____: dynamic or static
Dynamic. To ensure that the IP address for the resource remains the same (or static), one has to set the allocation method explicitly to static.
A static public ip address is released when –
- You delete the resource or
2. Change the IP allocation method to dynamic.
A dynamic public ip address is released when –
- You stop the resource
2. You delete the resource
SKUs of Public IP Address
- Basic SKU
2. Standard SKU
Public IP Address - Basic SKU vs Standard SKU
- Basic IPs are open by default, so the use of Network security groups is recommended for restricting inbound or outbound traffic.
- Standard IPs are secure by default and closed to inbound traffic. You must explicitly allow inbound traffic by using a network security group.
- Basic IPs do not support availability zone scenarios
- Standard IPs are zone-redundant by default
You can’t bring your own public IP addresses from on-premises networks into Azure - True/ False
True
Public IP addresses can’t be moved between _____; all IP addresses are _____-specific. Region/Subscription/VNet
Region
If your business needs to have datacenters in different regions, you will have a different public IP address range for each region
Public IP address prefix
- To ensure a static range of public IP addresses
- The advantage of a public IP address prefix is that you can specify firewall rules for these IP addresses with the knowledge that they will not change.
- You can assign the addresses from a public IP address prefix to any resource in Azure that supports public IP addresses.
DNS is split into two areas:
Public, and Private DNS
Integrating on-premises DNS with Azure VNets
Forwarding takes two forms:
Organizations often use an internal Azure private DNS zone for auto registration, and then use a custom configuration to forward queries from external zones to an external DNS server. Forwarding takes two forms
Forwarding - specifies another DNS server (SOA for a zone) to resolve the query if the initial server cannot.
Conditional forwarding - specifies a DNS server for a named zone, so that all queries for that zone are routed to the specified DNS server.
If the DNS server is outside Azure, it doesn’t have access to Azure DNS on 168.63.129.16. In this scenario, setup a DNS resolver inside your VNet, forward queries to it, and then have it forward queries to 168.63.129.16 (Azure DNS). Essentially, you’re using forwarding because 168.63.129.16 is not routable, and therefore not accessible to external clients.
Application owners need to use dynamic IP addresses for specific resources on their VNet. Which SKU must they choose? Basic or Standard or Both
Basic - Standard SKU public IP addresses always use the static allocation method. Basic SKU public IPs can be assigned by using static or dynamic allocation methods.
Network traffic between peered virtual networks is ____public/ private.
private. The traffic between virtual machines in peered virtual networks uses the Microsoft backbone infrastructure, and no public Internet, gateways, or encryption is required in the communication between the virtual networks.
Connects Azure virtual networks in the same region.
Regional VNet peering
Connects Azure virtual networks in different regions
Global VNet peering
Advantages of Peering
- Low-latency,
- High-bandwidth connection
- Ability to apply network security groups in either virtual network
- Ability to transfer data between virtual networks across Azure subscriptions, Azure Active Directory tenants, deployment models, and Azure regions.
Is there a downtime to resources in either virtual network during the creation of peering?
No
When you add a peering on one virtual network, the second virtual network configuration is automatically added - True/ False
True