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Step-by-Step Guide: DNS based traffic load balancing with Azure Traffic Manager (PowerShell Guide)

In my previous blog post, I explained how to setup an Azure Traffic Manager. In there, I used GUI method to set it up. In this post I am going to show how we can set up Azure Traffic Manager using Azure PowerShell.

In this demo, I am going to demonstrate how we can use Azure traffic managers to improve the application/service performance by pointing users to the closest endpoint. This demo includes the following tasks,

1. Setup two new resource groups (East US, UK South)
2. Setup two new windows VM (East US, UK South)
3. Setup IIS with sample web page
4. Create a Traffic Manager profile
5. Add endpoints to Traffic Manager profile
6. Testing

Setup two new resource groups (East US, UK South)

Let’s go ahead and start the setup process by creating a new Azure resource group.

For the configuration process, I will be using Azure PowerShell. Therefore, please make sure you have an Azure PowerShell module installed. More info about it can find under https://docs.microsoft.com/en-us/powershell/azure/install-az-ps?view=azps-2.6.0

1. Launch PowerShell console and connect to Azure using Connect-AzAccount
2. Then create a new resource group using,

New-AzResourceGroup -Name REBELRGEUS -Location “East US”
New-AzResourceGroup -Name REBELRGUKS -Location “UK South”

In the above, we are creating two resource groups. The first one called REBELRGEUS and it is created on East US Azure region.
The second group is called REBELRGUKS and it is created on UK South azure region.

Setup two new windows VM (East US, UK South)

1. In this demo, I am going to use two back end servers. Before VM setup, let’s go ahead and create a new virtual network in REBELRGEUS resource group

$vmsubnet = New-AzVirtualNetworkSubnetConfig -Name vmsubnet -AddressPrefix “10.0.2.0/24”

New-AzVirtualNetwork -Name REBELVN1 -ResourceGroupName REBELRGEUS -Location “East US” -AddressPrefix “10.0.0.0/16” -Subnet $vmsubnet

In the above, REBELVN1 is the new virtual network name. It has 10.0.0.0/16 address space. It also has a new subnet 10.0.2.0/24 (vmsubnet) for virtual machines.

2. Then let’s go ahead and create another virtual network under REBELRGUKS resource group.

$vmsubnet2 = New-AzVirtualNetworkSubnetConfig -Name vmsubnet2 -AddressPrefix “10.1.3.0/24”

New-AzVirtualNetwork -Name REBELVN2 -ResourceGroupName REBELRGUKS -Location “UK South” -AddressPrefix “10.1.0.0/16” -Subnet $vmsubnet2

In the above, REBELVN2 is the new virtual network name. It has 10.1.0.0/16 address space. It also has a new subnet 10.1.3.0/24 (vmsubnet2) for virtual machines.

3. As the next step of the configuration, I am going to create a new virtual machine under REBELRGEUS resource group. This will be used for testing purposes.

$mylogin = Get-Credential

New-AzVm -ResourceGroupName REBELRGEUS -Name “REBELTVMEUS” -Location “East US” -VirtualNetworkName “REBELVN1” -SubnetName “vmsubnet” -addressprefix 10.0.2.0/24 -PublicIpAddressName “REBELTVMEUSIP1” -OpenPorts 3389,80 -Image win2019datacenter -Size Standard_D2s_v3 -Credential $mylogin

[Read more…] about Step-by-Step Guide: DNS based traffic load balancing with Azure Traffic Manager (PowerShell Guide)

Step-by-Step Guide: DNS based traffic load balancing with Azure Traffic Manager

In my previous blog post, I explain how we can use Azure load balancer to distribute network traffic to endpoints in the same Azure region. It can be accessed using https://www.rebeladmin.com/2020/01/step-step-guide-setup-azure-load-balancer/ . But we can’t use the same method to distribute traffic to different Azure regions. For that, we have to use the Azure Traffic Manager.

The azure traffic manager is a DNS based traffic load balancer. It does have the following characteristics,

• Based on the traffic-routing method, it can route traffic to the closest endpoints to the user. This will improve the application/service performance.
• When an endpoint is not available, the traffic will automatically route to the most appropriate endpoint.
• Application/service maintenance can be done without any downtime. During the maintenance, traffic can redirect to other available endpoints.

In this demo, I am going to demonstrate how we can use Azure traffic managers to improve the application/service performance by pointing users to the closest endpoint. This demo includes the following tasks,

1. Setup two new resource groups (East US, UK South)
2. Setup two new windows VM (East US, UK South)
3. Setup IIS with sample web page
4. Create a Traffic Manager profile
5. Add endpoints to Traffic Manager profile
6. Testing

Setup two new resource groups (East US, UK South)

Let’s go ahead and start the setup process by creating a new Azure resource group.
For the configuration process, I will be using Azure PowerShell. Therefore, please make sure you have an Azure PowerShell module installed. More info about it can find under https://docs.microsoft.com/en-us/powershell/azure/install-az-ps?view=azps-2.6.0

1. Launch PowerShell console and connect to Azure using Connect-AzAccount
2. Then create a new resource group using,

New-AzResourceGroup -Name REBELRGEUS -Location “East US”

New-AzResourceGroup -Name REBELRGUKS -Location “UK South”

In the above, we are creating two resource groups. The first one called REBELRGEUS and it is created on East US Azure region.

The second group is called REBELRGUKS and it is created on UK South azure region.

[Read more…] about Step-by-Step Guide: DNS based traffic load balancing with Azure Traffic Manager

Step-by-Step Guide: How to configure Azure Private DNS? (PowerShell Guide)

If we are in an Active Directory environment, we can use windows DNS services to manage DNS records. This allows us to connect to hosts using their FQDN. When a new host added or when host IP address updated, relevant DNS entries are get updated automatically. Also, the same DNS servers can use to create custom DNS records. 

If it is not an Active Directory environment and still wants to use DNS services, we have to use a custom DNS solution. In such a situation most of the time we need to manually add/update DNS records. 

So, what about Azure environment? Does the same apply to it? 

Azure DNS is a managed DNS solution. We can use it for public DNS records as well as for private DNS records. Using Azure private DNS, we can resolve DNS names in a virtual network. 

Azure Private DNS has following benefits, 

• No additional servers – We do not need to maintain additional servers to run DNS solution. It is a fully managed service. 

• Automatic Record Update – Similar to Active Directory DNS, we can configure Azure DNS to register/update/delete hostname records for virtual machines automatically. 

• Support common DNS records types – It supports common DNS records types such A, AAAA, MX, NS, SRV, TXT. 

• DNS resolution between virtual networks – Azure Private DNS zones can be shared between virtual networks.

In this demo, I am going to demonstrate how to create an Azure private DNS zone.

For the configuration process, I will be using PowerShell. Therefore, please make sure you have Azure PowerShell module installed. More info about it can find under https://docs.microsoft.com/en-us/powershell/azure/install-az-ps?view=azps-2.6.0

Let's go ahead and start the configuration process by creating a new resource group. 

1. Launch PowerShell console and connect to Azure using Connect-AzAccount

2. Then create a new resource group using,

New-AzResourceGroup -Name REBELRG -Location "East US"

In the above, REBELRG is the resource group name and East US is the resource group location.

3. The next step is to create a new virtual network.

$vmsubnet  = New-AzVirtualNetworkSubnetConfig -Name vmsubnet -AddressPrefix "10.0.2.0/24"

New-AzVirtualNetwork -Name REBELVN1 -ResourceGroupName REBELRG -Location "East US" -AddressPrefix "10.0.0.0/16" -Subnet $vmsubnet

[Read more…] about Step-by-Step Guide: How to configure Azure Private DNS? (PowerShell Guide)

Step-by-Step Guide to manage DNS records in Azure Managed Domain (AAD-DS)

In my recent articles I was explaining how to enable Azure Active Directory Domain Service and how to manage its services using domain-joined server.

If you not read it yet please check my last post in here.

When you manage a local active directory instance, using DNS mmc you can manage the DNS records. But can we do same with Azure managed domain? Answer is yes. In this post I am going to show how to manage dns records using domain-joined azure vm.

In order to do that we need following prerequisites.

1)    Azure Active Directory Domain Service (AAD-DS) managed domain Instance
2)    Domain Joined Virtual Server
3)    User account with member of AAD DC Administrators group

I have explain all of above in my last 3-4 posts. Please follow them if you like to know more about those.
So in this demo, I am going to use the already setup Azure managed domain instance.

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I also have a virtual server running on Azure with windows server 2016 TP5. It is already jointed to the managed domain.

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To start with the configuration RDP to the virtual server

1)    Log in to server with member account of AAD DC Administrators group

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2)    Open Server Manager > Add Roles and Features

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3)    In first screen of wizard click on next to proceed

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4)    In next window keep the default and click next

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5)    In server selection keep it default and click next

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6)    In server roles keep default and click next

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7)    Under the features, go to Remote Server Administration Tools > Roles Administration Tools > DNS Server Tools. Then click next to proceed

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8)    In next confirmation window click on install to install the tools

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9)    Once it’s done go to server manager > tools > DNS

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10)    On first start it will prompt where to connect. In their select the option as below and then type the managed domain you have in place. Then click ok

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11)    It will open up the DNS mmc.

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In here we can manage the DNS records as we need. There are some dns records which related to the managed domain service. So make sure those records are not modified or deleted.

The virtual machine no need to be on server version, if you install desktop version you can still managed dns by installing RSAT tools.

If you have any questions about the post feel free to contact me on rebeladm@live.com

Azure DNS

Azure DNS is now fully supported in the Azure Portal. Even it’s remain on preview mode it’s not too soon to start your testing before introduce to the production environment.

In your local AD infrastructure, AD DNS service is taken care of all your DNS entries. It can be A records, mail server records (MX), CNAME records, service records etc. the same methodology apply for the public domain names as well. For example let’s assume there is public domain name called contoso.com. There is web server which host contos.com web site and its ip address is 38.112.6.100. Also there is mail server running on 38.112.6.101. So I need A record for the web site and MX record for mail service. But how public internet know these values? I need DNS server to serve DNS enquires from internet.

There is few way to do this. Domain registrar allow to use their own DNS servers to setup your DNS records. Some do this as free service and some provide it as paid service. Also if you need you can setup your own DNS server and point public domain names to it.

Before choosing one of the above options it’s important to consider,

1)    Availability of the DNS servers – what if Primary DNS server go down? How to handle such situation and keep the organization services up and running?
2)    Performance – How to handle the DNS queries and provide faster response time?
3)    Fast DNS Updates – Normally if you add new DNS record or update existing record it can take 4-48 hours to fully resolve through internet.  But this can make impact based on the organization requirements. 

Why Azure DNS?

With Azure DNS, you can host your DNS domains in Azure. Manage your DNS records using the same credentials and billing and support contract as your other Azure services. Seamlessly integrate Azure-based services with corresponding DNS updates, streamlining the end-to-end deployment process.

Azure DNS uses a global network of name servers to provide fast responses to DNS queries. Because we use Anycast networking, DNS queries automatically route to the closest name servers for the best possible performance.

The Microsoft global network of name servers has the scale and redundancy to ensure ultra-high availability for your domains. With Azure DNS, you can be sure that your DNS will always be available.

When you add a new DNS record, the Azure DNS name servers are updated in just a few seconds, so you don’t have to wait long before that DNS record can be used.

Source: https://azure.microsoft.com/en-gb/services/dns/

Now theory is over, let’s see it in action.

In my demo, I am going to use one of my domain therebeladmin.com and point it to Azure DNS. Then going to create A record to point it to my web server.

1)    Log in to Azure Portal as administrator (https://portal.azure.com)
2)    Go to New > type DNS. Then from the search result click on “DNS Zone”

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3)    Then it will open up the service description window. Click on “Create” to start

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4)    Then in next window, provide the domain name as the name field, then you need to select the subscription. Also in page you can select which resource group it belongs to.  It gives opportunity to select the location this service should locate primarily. Once its completed click on “Create”

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5)    Once service is successfully commissioned it will appear in the portal home. Or else if you go to “All Resources” you will be able to find the DNS service just deployed. Click on it to start configurations.

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6)    In the page it shows the detail of the configurations. To point therebeladmin.com to Azure DNS, I need to point name servers to it from my domain registrar end.

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7)    My web server is running on 38.117.80.2 so I need to create A record for that. To do that click on “Record Set” icon

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8)    Now in new window i am creating A record to point the website. Once done changes click on OK to create the record.

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9)    I am also creating CNAME record for WWW. So if someone type www.therebeladmin.com in the web browser it will resolve correctly. Also MX record too.

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10)    Now I can see the new records I added in the web page.

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Next step is to go to domain registrar and update name server records so it’s pointed to Azure DNS.

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Using a public too I check the dns status and now I can see Azure DNS records are resolving correctly.

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If you have any questions feel free to contact me on rebeladm@live.com