I'm curious if the FQDN is persistent on Virtual Machines in Azure and if anyone could post an example how this would look.
Ie myhost-abc.vm.windows.net
By persistent I mean it will always be the same, never to be changed.
Connect to your virtual machine with Remote Desktop (RDP)
Open a command prompt
Type this command: hostname (to show the name of the machine)
Type this command: nslookup "MACHINE_NAME" (where "MACHINE_NAME" is the obtained during the previous step)
The result show Name (FQDN) and address, in my case: MYSERVER.MYDOMAIN.f5.internal.cloudapp.net is always the same.
When you create a Windows Azure Virtual Machine (or Windows Azure Cloud Service) you first select a name for your service and based on your service name a DNS name is assigned to you. So example you have choosen service name ( with both VM or CS) "myservice" your DNS name will be and will remain same forever as long as you delete this service:
http://myservice.cloudapp.net
Now when create a Virtual Machine in service (or deploy your cloud application to this cloud service) you will have a VIP (external facing) assigned to your service and depend on your service endpoint configuration your service will interact to externally. These IP address will stay same as long as you do not delete the virtual machine(s) or deployment.
Also you can use CNAME setting (or DNS record) to route www.myservice.com calls to myservice.cloudapp.net this way if you change myservice to myservice1 by any reason, after setting proper CNAME your www.myservice.com call still go to your Azure service (VM or CS).
http://www.myservice.com ==>> http://myservice.cloudapp.net or http://myservice1.cloudapp.net
As you can see it does not matter if you choose myservice or myservice1 as service name, by setting proper CNAME/DNS setting you can route your actual DNS to Azure Service.
Just an addition. For Linux, do:
nslookup "$(hostname)"
Related
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.
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.
I have a Azure WebApp inside the VPN. When I go on networking I see the connection like this:
When I click on "Click here to configure"it appears to be up & running:
So, everything appears OK.
The VPN externally connects BUT where can I find the Internal "VPN" IP Address of this Web App?
If I go on configurations / SCM etc I can only find the "external" IP!
Thanks
If you have a normal App Service then you can't get it's IP, mainly because the application is running on a distributed environment and the exact location of the instance might change with little notice.
If you need a dedicated public (or private) IP, then I recommend you have a look at Azure App Service Enviroments.
I've been running the free trial and am trying to point of my name cheap domain to the vm web site I have created.
I covered the server Ip.
Here are my namecheap settings for the domain.
The covered Ip is the same as above..
Here are my IIS settings
Change the Hostname to my actual domain.
I've also disabled Windows firewall and added port 80 and 443 in the security app hooked to the Azure VM. I can't seem to connect to the website at all. Am I missing something? I've been troubleshooting for hours and cant find anything except basic tutorials and how to do it on the Classic Azure portal.
thank you.
If you are using V1 (old portal/classic) Azure VM resources, then you need to open up the endpoint on the cloud services. All VMs exist as part of a Cloud Service.
From the new portal,
Select the VM (Classic)
Settings
Endpoints
Add the required port (make sure public port is the one you want to use, say 80, and the internal port is the one IIS is listening for)
If you are using V2 resources, you need to add a public IP to your VM before it can be reached from the outside world.
From the new portal
Click on the VM
Open settings
Select Network Interfaces
Select IP Address
Enable public IP (and add a PIP)
Keep in mind that in Azure, all IPs are dynamic. You will want to configure DNS settings against the DNS names provided, and not the IP address (as this will change if you power off the machine). For V1, use the cloud service name. For V2, you are given the option when creating the PIP to have azure assign a DNS name.
For testing, try to telnet on port 80 to the correct DNS name.
I had a need to add additional public IP addresses to an Azure VM and found a working solution here:
Azure VM: More than one Public IP
Essentially this creates a reserved IP in Azure and then adds the reserved IP to a cloud service. Once it's bound to a cloud service it can be mapped to a VM endpoint.
This all works great but there is one bit I don't understand - The IP address of the reserved IP and the resultant VM endpoint don't match. I have to set up DNS to point to the IP address of the endpoint to make this work. Is there something I am not doing right, or is this just the way reserved VMs work?
It looks like this unanswered question is the same issue:
azure reserved IP for VM is diffrent than the given
Thanks!
The "Azure Cloud Service" is a container that provides internet connectivity to "Azure VMs". Thus, you assign the Internet facing Public IP to the Cloud Service. This article is relatively good at explaining the relationship: Azure Cloud Services
From above link:
Here’s a definition of an Azure IaaS cloud service that will make it easy for you to understand what it is in the context of Azure Infrastructure Services:
A cloud service is a network container where you can place virtual machines.
All virtual machines in that container can communicate with each other directly through Azure (and therefore don’t have to go out to the Internet to communicate with each other).
This container is also assigned a DNS name that is reachable from the Internet.
A rudimentary DNS server is created and can provide name resolution for all virtual machines within the same cloud service container (note that name resolution provided by the DNS server is only available to the virtual machines that are located within the cloud service).
One or more Virtual IP Addresses (VIPs) are assigned to the container and these IP addresses can be used to allow inbound connections from the Internet to the virtual machines.
Certain services (like FTP) may require your vm have a public IP: Azure VM Public IP
(IaaS v1) An Azure cloud service comes with a permanent DNS name - something.cloudapp.net - and has a single VIP allocated whenever there are VMs deployed in it OR whenever a reserved IP address is associated with it. Traffic is either load balanced or NATted (port forwarded) to the VM from the Azure Load Balancer sitting on the VIP. You can also associate a public instance-level IP address (PIP) with a VM, which gives it an additional IP address. The VIP always has a DNS name (something.cloudapp.net) while the PIP has one only if you specifically add it, I did a post which goes into these differences.
(IaaS v2) VMs are not deployed into cloud services and only have a public IP address if one is specifically added - either by configuring a PIP on the NIC of the VM (and optionally giving it a cloudapp.azure.com DNS name) or by configuring a load balancer and either load balancing or NATting traffic to it. This load balancer is configured with a public IP address and can optionally have a cloudapp.azure.com DNS name associated with it. (Ignoring internal load balancers in this discussion.)