I provisioned the resources accordingly to the documentation.
https://learn.microsoft.com/en-us/azure/postgresql/flexible-server/concepts-networking
I did the provisioning using BICEP.
The name of the server is my-dev-db and I created a DNS private zone:
my-dev.postgres.database.azure.com
Now what I see, is that from my local computer, so public internet, I can ping both
my-dev.postgres.database.azure.com
and
my-dev-db.postgres.database.azure.com
I created a VM in the same VNET and I managed to connect via postgres client, but, not to the private DNS, my-dev.postgres.database.azure.com but to the my-dev-db.postgres.database.azure.com which is the one automatically created by azure as server name. When I try to connect with the private DNS it doesn't resolve.
So my question:
Why can I ping both dns from outside Azure.
Why the private dns doesn't resolve in the VM.
Really can't make sense of this behavior.
Related
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
I have an Azure logical SQL server to which I added a Private Link, the NIC is attached to an existing vnet\subnet. Our company's VPN is linked to that vnet and I can see other devices on the private link's subnet but not the SQL Server.
The SQL Server is reachable on the public URL (temporarily for testing) but trying to ping or tracert the server with the private IP fails, I can ping and tracert to other VMs on the same subnet.
I'm not using a custom DNS zone because it's imperative that we configure it with the IP and I haven't made any changes to our company DNS (I'm expecting not to have to).
Other than creating the private link and attaching it to the SQL Server, what else needs to be done? What am I missing?
I'am working on the same Issue. It's still not solved yet but there are some steps you need to do.
For the Connectivity it's required to add a DNS, especially if you want to connect from the On-Prem. Azure has a default DNS-Solution for Azure-Resources. The Problem is: From On-Prem you can't access the default Azure-DNS-Service.
So you have to configure a DNS-Zone (in Azure or On-Prem).
I have a Private AKS cluster deployed in a VNET on Azure. Once I deployed it, a private endpoint and a private DNS zone were created by default therefore making the cluster accessible from VM's which are part of the same VNET. (I have a VM deployed in the same VNET as the AKS cluster and "kubectl" commands work in it.)
My requirement is that I want to perform the "kubectl" commands from my local machine (connected to my home network) and also connected to the VPN which connects to the VNET.
My machine can talk to resources within the VNET but cannot seem to resolve the FQDN of the private cluster.
I read somewhere that having a DNS forwarder setup in the same VNET can help resolve the DNS queries made from the local machine which can then be resolved by Azure DNS. Is this the way to go about this? Or is there a better way to solve this problem?
It would really help if someone could give me an action plan to follow to solve this problem.
The better way to perform the "kubectl" commands from your local machine to your private AKS cluster is to use AKS Run Command (Preview). This feature allows you to remotely invoke commands in an AKS cluster through the AKS API. This feature provides an API that allows you to, for example, execute just-in-time commands from a remote laptop for a private cluster. Before using it, you need to enable the RunCommandPreview feature flag on your subscription and install aks-preview extension locally. However, there is a limitation that AKS-RunCommand does not work on clusters with AKS managed AAD and Private link enabled.
In this case, If you want to resolve the FQDN of the private cluster from your on-premise network, you could select to use either the hosts file locally(used for testing) or use your DNS forwarder to override the DNS resolution for a private link resource like this.
The DNS forwarder will be responsible for all the DNS queries via a server-level forwarder to the Azure-provided DNS 168.63.129.16.You can provision IaaS Windows VM with DNS role or Linux VM with bind configured as a DNS forwarder. This template shows how to create a DNS server that forwards queries to Azure's internal DNS servers for Linux VM. Refer to this for DNS forwarder on Windows VM.
If there is an internal DNS server in your on-premise network. The on-premises DNS solution needs to forward DNS traffic to Azure DNS via a conditional forwarder for your public DNS zones(e.g. {region}.azmk8s.io). The conditional forwarder references the DNS forwarder deployed in Azure. You could read this blog about DNS configuration sections for more details.
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 followed the documentation guide here to configure an Azure DNS zone for a virtual network.
I then created a virtual machine on that virtual network and provisioned a virtual network gateway to allow my Azure web apps to communicate with the virtual machine using VNet integration. My web apps are then able to resolve against the virtual machines private IP as expected.
I then created an 'A' type record set within the DNS zone resolving a service name against the private IP of the virtual machine just like here.
However, when I then attempt to access the DNS configured service name that should resolve against the private IP address of the virtual machine, I get the following error:
curl: (6) Could not resolve host: xxxx.local
Am I missing something obvious here?
I can not reproduce this error following your steps:
Create an Azure VNet with a DNS private zone like private.test.com.
Create a VM and a VPN gateway on that VNet.
Enable VNet integration with my Azure web app service.
My web apps are able to resolve against the virtual machines private IP as expected. This could verify the Azure private DNS zone should work. Then I also create an A record for a custom name against the VM private IP address. Both scenarios work.
You could check if an A record is something like below picture in the private DNS zone.
Then you could verify if curl with http:// or without that, or without the specific port 9200, the error is still the same.
I suggest using SET WEBSITE_DNS_ command. This command will output the current DNS server that is being used by the web app. If the error Environment variable WEBSITE_DNS_ not defined is received, no custom DNS servers are configured for the web app. See more details about networking Related Commands for Azure App Services.