I have hosted my web application in azure, My team accessing my application vi application gateway private ip using Azure P2P VPN connection. My application is working with private IP, I want to configure dns name and ssl certificates for my private ip.
Following things I have tired so far
Created Azure Private DNS Zone and Linked my VNets
Created A records for my private ips
Added dnssuffixes in azurevpnconfig.xml (Azure VPN Client configuration)
I tried accessing test.demo.com, I'm getting site not be reached
Not sure what I'm missing
Clarification would be helpful
Azure wont support private dns configuration for P2S VPN connection ?
Any other workaround to achieve dns and SSL configuration for private IPs ?
Reference :
https://learn.microsoft.com/en-us/answers/questions/64223/issue-with-resolving-hostnames-while-connected-to.html
https://learn.microsoft.com/en-us/azure/vpn-gateway/vpn-gateway-troubleshoot-vpn-point-to-site-connection-problems
As per Name resolution for resources in Azure virtual networks:
In order for the P2S VPN clients to be able to resolve Private Endpoint entries hosted on Azure Private DNS Zones, you must leverage an existing DNS Server (Forwarder or Proxy) or deploy one IaaS VM using a DNS Server role. That is required to P2S VPN clients be able to consume Azure Private DNS Zone which is exposed to 168.63.129.16 via DNS Forwarder/Proxy.
Once you have a DNS forwarder/proxy deployed on Azure, you can define the DNS server at the VNET level or set DNS Server configuration directly on client XLM profile. Post this, you will be able to resolve Private Endpoint entries from your P2S clients.
Refer : https://learn.microsoft.com/en-us/azure/private-link/private-endpoint-dns#on-premises-workloads-using-a-dns-forwarder
https://github.com/dmauser/PrivateLink/tree/master/DNS-Integration-P2S
Related
I have the following situation:
If I deploy an application (Deployment, Service and Ingress) in my kubernetes cluster, my ingress deployment is being automatically added to my application gateway (I am using the Azure Application Gateway Ingress Controller; https://azure.github.io/application-gateway-kubernetes-ingress/annotations/ ). So far so good.
That means that my application can be reached via my application gateway via https://my-app-gateway-public-ip/myAppPath/. Also, I have an additional private DNS zone which makes my app accessible via https://dns-name/myAppPath.
Additionally, we have an AADDS in combination with a Bastion Service. Deployed some virtual machines and the virtual machines use the DNS resolver of the AADDS (for authentication against the AAD).
The problem is: If I am outside of the cloud, I can nslookup the dns or can access the site via the ip, but I cannot do that with my virtual machines. My DNS server (within the AADDS) is unable to resolve the dns or accessing the ip. I am wondering what the issue is.
The bastion and AADDS are in different subscriptions and therefore different virtual networks. I established already a peering between those virtual networks (or the authentication between the AADDS and the VMs wouldn't work).
The kubernetes cluster and the application gateway are also in a different subscription, but no peering has been done so far.
Are there any hints what I could be missing?
Kind regards
• Since, you are using a Bastion gateway server to connect to the VMs hosted in your subscription, the Bastion gateway server must be having a public IP address through which then the registered underlying VMs can be connected to via private links created in the private DNS zones associated with a particular virtual network in a subnet and an assigned private IP address and a FQDN accordingly. Thus, if you want to access the application website hosted behind the application gateway, then you will have to create a conditional forwarder in the DNS zone in AADDS to redirect the internal requests from the VMs hosted within a virtual network to the public IP address of the website hosted behind the application gateway
• Thus, a conditional forwarder forwards the DNS resolution requests for a particular resource hosted on the public internet for which the DNS host resolution is not found or done in that DNS zone which usually serves or fulfils the requests related to internal environment. As a result, when a VM configured with a private IP is registered as a host in the internal DNS zone queries the public IP or FQDN associated with the application’s website, the DNS requests are forwarded to the public internet through the conditional forwarder and then the results are displayed in the VM’s browser for the application’s webpage. Thus, the VMs don’t need to have internet access but the DNS server should have or should forward the requests through the Internet proxy server accordingly to reach the internet.
For more information on creating conditional forwarder in AADDS, kindly refer to the below link: -
https://learn.microsoft.com/en-us/azure/active-directory-domain-services/manage-dns#create-conditional-forwarders
I am trying to access resources that are secured behind private endpoint from a remote location using an Azure VPN Point-to-Site connection.
So far I have setup a conditional forwarder to send DNS requests to Azure's internal DNS IP address (168.63.129.16). With my setup I can resolve all my private endpoints using nslookup to their private IP addresses. I can also connect to services such as SQL server from my local machine (using SQL Server Management Studio in the case of SQL server).
The problem I am facing is that I can only access resources if I use a desktop client for a given service. If I try to do anything using the Azure Portal, I get an error stating that I cannot access resources using my Public IP address without adding it as an inbound IP address. Whilst this is certainly an option, I don't want to go down this road.
I am hoping there is an option where I can connect to private endpoint resources from Azure Portal whilst connected to my point-to-site VPN. Any ideas?
So far I have setup a conditional forwarder to send DNS requests toAzure's internal DNS IP address (168.63.129.16). With my setup I can resolve all my private endpoints using nslookup to their private IP addresses. I can also connect to services such as SQL server from my local machine (using SQL Server Management Studio in the case of SQL server.
AfAIK, the process which you are doing is correct, To fix this issue try to update the local host file on client desktop to deploy a recourse with private endpoint please refer this link for more in detail
By default when you create a Private Endpoint in the Azure Portal it will automatically lock out public access. Service Endpoints operate by adding routes to allow traffic out of the virtual network to reach the public endpoint of the service selected. If you are access resources error, update firewall rules to communicate with your Azure resources you really need to configure v-net traffic on the firewall settings
Next option is conditional forwarder, in your scenario the ble from every v-net, its public ip it won't overlap with any private ips, it available from inside of azure v-net unique to each
In conditional for forwarder, client asks the ip of a host like www.seraltos.com .The dns server looks to see the answer if knows, if not a lookup will done based on root servers or forwarder to find the ip address returns that to the client
For more information in detail, please refer below links:
Private Endpoints and DNS in Azure & Cannot access my own public IP
https://learn.microsoft.com/en-us/azure/storage/common/storage-private-endpoints
https://learn.microsoft.com/en-us/azure/private-link/manage-private-endpoint?tabs=manage-private-link-powershell
PROBLEM:
I'm able to connect to the Azure SQL Database using the private link from VM within the virtual network, but not from my pc trough virtual network gateway
In sqlserver1 firewall, I have denied public network access.
From MyVM in the myvnet, I'm able to connect to the sqlserver1 using FQDN. nslookup shows correctly private address 10.0.0.4
I connected my pc to the vnet using the gateway. I'm able to ping MyVM using private adresss 10.0.0.5.
When I try to connect to the sqlserver1 using FQDN, I get error:
An instance-specific error occurred while establishing a connection to
SQL Server. The public network interface on this server is not
accessible. To connect to this server, use the Private Endpoint from
inside your virtual network. (Microsoft SQL Server, Error: 47073)
So it looks like that it's using the public dns record and not the private dns zone that I have created with the private endpoint. How can I connect to the database?
In this case, you can use NSLOOKUP FQDN on the PC to verify if the private DNS zone issue.
You need to correctly configure your DNS settings to resolve the allocated private IP address. You can follow On-premises workloads using a DNS forwarder and this blog about Azure SQL DB Private Link / Private Endpoint - Connectivity Troubleshooting.
It's not recommended to override a zone that is actively in use to
resolve public endpoints. Connections to resources won't be able to
resolve correctly without DNS forwarding to the public DNS. To avoid
issues, create a different domain name or follow the suggested name
for each service below.
To configure properly, you need the following resources:
On-premises network
Virtual network connected to on-premises
DNS forwarder deployed in Azure
Private DNS zones privatelink.database.windows.net with type A record
Private endpoint information (FQDN record name and private IP address)
I am trying to connect an on-premises laptop with dynamic external IP to our Azure SQL Server. To do this, I created a virtual network gateway and connected the laptop to the gateway. Also, I added a private endpoint to the SQL server. After this, I can successfully connect to the SQL server IP using telnet, and if I resolve the SQL server FQDS in hosts file, I can connect to the server via SSMS. But without hosts file, the laptop always tries to connect to the SQL server via its public endpoint/address.
I found the following article: https://techcommunity.microsoft.com/t5/azure-database-support-blog/azure-sql-db-private-link-private-endpoint-connectivity/ba-p/1235573 The article is great. It recommends using your own DNS server to resolve the SQL server FQDN to the local IP. Unfortunately, the laptop does not have access to any custom DNS, so this solution does not suit.
There are two questions:
Is there any possibility to establish connection between an on-premises computer with dynamic IP and an Azure SQL server using a private endpoint but without own DNS server?
If the answer to the first question is "No", is there another way to connect an on-premises computer with dynamic IP to an Azure SQL server using any other Azure application(s)?
First of all, you can not use FQDN without DNS service. So you indeed need a custom DNS server in using FQDN of the server in connection strings for your clients to connect from on-premise VM to the Azure SQL server.
Since you are using a laptop, the DNS servers used by your computer are most likely specified by your ISP. You have no more control over it or ask your ISP to configure the DNS forwarder. Otherwise, you need to deploy a DNS server in your internal network. Currently, in this scenario, the best method is to use the HOSTS file on the local machine to override the Public DNS.
However, if you don't like using the HOSTS file, you can provision an Azure VM as the DNS server in the same Azure virtual network as the virtual network gateway.
Main steps:
Deploy an Azure VM, and RDP to that VM and run the PowerShell commands to install the DNS server role.
Install-WindowsFeature -Name DNS -IncludeManagementTools
Get-WindowsFeature *DNS*
Add Azure DNS (168.63.129.16) as a forwarder on your custom DNS server according to the step 5 in this blog. If you do not want to use forwarder you can also create a forward lookup zone and added manually the host to match the FQDN. You could read On-premises workloads using a DNS forwarder for more details.
After you have configured the DNS server and set the DNS forwarder. You could change the DNS server of Azure VNet to your Azure VM's private IP address.
Restart your Azure VM and re-download the VPN client package and re-connect the VPN connection to make the networking update. Check the DNS server on the local VPN client machine and set the DNS server to the custom DNS server in the TCP/IP settings. Then you will look up your private IP address via the default FQDN of Azure service.
In my example, I am using Azure storage account but it works the same with Azure
SQL database when using a private endpoint on the Azure and P2S VPN connection.
In this way, it requires that there are not any other VPN connections except the
P2S VPN connection on the local machine.
Then you could resolve the Azure SQL server FQDN to the private IP address of the private endpoint. However, it perhaps does not have a better performance to connect to Azure SQL Server with a VPN connection than directly connect to it through the public Internet and public DNS sevice.
I'm migrating asp.net services that used to exist on a physical server on-premise to Azure. However they need to reach some web-services (SOAP) that will not be migrated to azure yet. These have a public IP but I need to set the hostname in order for IIS to properly redirect the requests to the correct service as there are several on the same server. Is there any way to create some sort of DNS-server in azure that is only available for the services created in azure that can resolve to the public IP-address outside of azure? (We have used the hosts file on the servers to achieve this previously)
I tried using the private DNS Zones, but as I've understood it they can only point to other azure services within the same vnet (correct me if I'm wrong). I've also tried creating a dnsmasq docker container. However, as this is running in a Linux container, it seems that I cannot put it in the same vnet as the asp.net app services. Thus I am unable to retrieve a private IP-address that these services can use to reach the DNS server.
In my understanding it is now possible to use Azure DNS Private Zones if you want.
You would need to use regional vnet integration to point your app's traffic to a vnet that is connected to the Private Zone. You need the following settings as well, which mean that all outbound traffic from the Web App is routed through the integrated vnet first, and that the Azure default DNS server is used for DNS.
WEBSITE_DNS_SERVER with value 168.63.129.16
WEBSITE_VNET_ROUTE_ALL with value 1
https://learn.microsoft.com/en-us/azure/app-service/web-sites-integrate-with-vnet#azure-dns-private-zones
If you don't want to use Azure DNS Private Zones, I think you can achieve similar results by directing the Web App to use a specific DNS server. This can be done using WEBSITE_DNS_SERVER and WEBSITE_DNS_ALT_SERVER app settings (the values are the IP addresses of the servers you want to use).
This is the most authoritative public statement I can find about using these settings.
Go to the web app->settings->Application Settings-> App Settings
section
Add the following: (WEBSITE_NODE_DEFAULT) should already be
there.
a. WEBSITE_DNS_SERVER with value having the IP address of the
primary DNS server.
b. WEBSITE_ALT_DNS_SERVER (optional), with value
having the IP address of a second DNS server.
Then save the settings & restart webapp in portal.
Double check the web app can actually
connect to the DNS server: a. In kudu console, run: Nameresolver.exe
[hostname-to-lookup] [dns-server-to-use]
First argument should be the
hostname you are trying to look up, second argument is one of the DNS
servers from step 1) If this times out, there is an issue with how
your DNS servers are configured (firewalls, etc.)
https://github.com/MicrosoftDocs/azure-docs/issues/13927#issuecomment-416382230
If using these settings with a DNS server that is only accessible via private IP, you would need to use regional vnet integration again to connect to a vnet. If the DNS server is on-prem, you have to connect through the integrated vnet over VPN or ExpressRoute.
It's possible but not using the private DNS Zone.
According to Name resolution for resources in Azure virtual networks. For the scenario Name resolution from App Service Web Apps in one virtual network to VMs in a different virtual network, you need to use your own DNS servers forwarding queries between virtual networks for resolution by Azure (DNS proxy). See Name resolution using your own DNS server.
In this case, you only allow this azure web service could resolve the public IP address outside of Azure. You could enable virtual network integration for your web app, this restricts your web app access in a private network. Then you could deploy a DNS server in the same Vnet as the web app integrated VNet. You could create an A type record in your DNS zone to point to your service Public IP, then add the DNS server's IP address into the DNS server of the Integrated web app Vnet in the portal. If so, the web app could resolve this public IP via a custom DNS server.
Hope this could help you.