We would like to create Azure App Service / Azure Function App resources for our new project and try to understand the IP Address Requirement. I am looking for this information so that I could allocate the subnet size accordingly.
Each App Service will just consume 1 App Address or More? I am new to App Service and haven't used the App Service before. So if someone could clarify in detail, it would be great.
I have created an App Service in our Virtual Network and I could see for Inbound Traffic one IP Address is Assigned and for Outbound, there are many IP Addresses assigned. So bit confused in allocating the IP Addresses.
There are a few IP addresses to be aware of in an App Service Environment. They are as follows:
Public inbound IP address: Used for external app traffic and management traffic in both internal and external deployments.
Outbound public IP: This is the IP address that is used as the "from" ip for connections that exit the virtual network. These connections do not go through a VPN.
Internal load balancer IP address: This address is solely used for internal purposes.
App-assigned IP-based TLS/SSL addresses: These addresses are only possible when using an external deployment and configuring IP-based TLS/SSL binding.
The App Service Environment UI in the Azure portal displays all of these IP addresses.
Please refer to these links as well for more information -
IP addresses ,
App Service Environment networking
Related
Playing with Azure App Service, I instantiated a simple web app. I tried to identify its IP address and found one in the properties of my app. It was described as 'virtual IP address'.
Trying to ping it or put it in my browser, it doesn't work and I can't find if it's an Azure configuration or a principle of virtual IP addresses... To be more precise, if I type '40.79.130.128' in my search bar, I crash on a 404 page, instead of my website page.
I read a bit on the topic, mainly what it is used for, but I don't understand if I can just reach it in my browser, because just typing it in my search bar is no use. What am I missing?
The Virtual IP address under your App Service on the blade Settings->Properties is the Shared IP.
The way IP address work in App Service is different. App Service app runs in an App Service plan, and App Service plans are deployed into one of the deployment units in the Azure infrastructure which is internally called a webspace and each of the deployment unit is assigned up to five virtual IP addresses, which includes one public inbound IP address and four outbound IP addresses.
All App Service plans in the same deployment unit, and app instances that run in them, share the same set of virtual IP addresses which means many App Services is behind same IP address hence you need to configure Custom Domain on your App Service to get it to work.
For configuring Custom domain refer to this link:
https://learn.microsoft.com/en-us/azure/app-service/app-service-web-tutorial-custom-domain
Please refer to below articles for details:
Inbound and outbound IP addresses in Azure App Service
App Service networking features
Azure App Service has 2 types of outbound IP addresses:
Outbound IP Address:
Additional Outbound IP address:
I would like to know from the whitelisting perspective, which category do I need to use in my firewall?
As far as I know, you should whiteliste the Additional Outbound IP addresses:
An App Service app runs in an App Service plan, and App Service plans
are deployed into one of the deployment units in the Azure
infrastructure (internally called a webspace). Each deployment unit is
assigned up to five virtual IP addresses, which includes one public
inbound IP address and four outbound IP addresses. All App Service
plans in the same deployment unit, and app instances that run in them,
share the same set of virtual IP addresses. For an App Service
Environment (an App Service plan in Isolated tier), the App Service
plan is the deployment unit itself, so the virtual IP addresses are
dedicated to it as a result.
Because you're not allowed to move an App Service plan between
deployment units, the virtual IP addresses assigned to your app
usually remain the same, but there are exceptions.
Source.
So for some exceptions like if you scale your app between tier, one or more of the four outbound IP addresses may change (with some of the additional outbound IP addresses)
See: When outbound IPs change
I have created one Web app on Azure portal and its integrated with subnet under specific VNET.
Now, when I am trying to do telnet to one of my organisation's internal relay server IP from my web app its not getting connected. The request is going from web app's APIPA address range not from subnet's address range. I checked the IP as well of the web app using ifconfig and I found out that its taking from APIPA address range not from subnet one.
Any idea what steps do I need to take so that web app will take IP from subnet address range of the VNET not from APIPA address range.
Thanks in advance.
After my validation, when the app service on Linux is integrated with a virtual network. There is an extra NIC binding to the app service. It's IP address from APIPA address range. It looks like a design behavior as the app service on Linux is running in a standard Docker Container, read here. Also, for a normal app service is a multi-tenant environment, you can not get a dedicated IP address unless you are using a dedicated environment---ASE, read here.
Furthermore, from how regional VNet Integration works, you will see the app service integrated with a vNet is not the same as a VM from a VNet.
Regional VNet Integration works by mounting virtual interfaces with
addresses in the delegated subnet. Because the from address is in your
VNet, it can access most things in or through your VNet like a VM in
your VNet would. The networking implementation is different than
running a VM in your VNet. That's why some networking features aren't
yet available for this feature.
In this case, if you wan assign a private IP address for app service, you can use Azure Private Endpoint with web apps(Preview). Read this blog for more details.
Azure Private Endpoint provides private IP address access by using a
network interface controller (NIC) attached to a virtual network
subnet for an Azure web app, allowing access from an on-premise VPN or
ExpressRoute. Implementing an endpoint effectively blocks the public
inbound access. This technology is very similar to an internal App
Service Environment (ASE) but much cheaper.
We are currently validating a workflow which would involve whitelisting IP addresses from Azure in order to be able to talk to specific servers that we own. Our plan is to use Azure App Service Environment to be able to get a static IP address we could use (so that all app services running under that environment would be able to talk to our servers). My question -
Though the public VIP is described in detail, I couldn't find any documentation that describes cases when it could change or be disassociated from the App Service Environment.
Are there additional configurations/specific pricing tiers that we should follow in order for us to safely assume that we would not lose ownership of the public VIP we are whitelisting
ASE IP addresses
An ASE has a few IP addresses to be aware of. They are:
Public inbound IP address: Used for app traffic in an External ASE, and management traffic in both an External ASE and an ILB ASE.
Outbound public IP: Used as the "from" IP for outbound connections from the ASE that leave the VNet, which aren't routed down a VPN.
ILB IP address: The ILB IP address only exists in an ILB ASE.
App-assigned IP-based SSL addresses: Only possible with an External ASE and when IP-based SSL is configured.
All these IP addresses are visible in the Azure portal from the ASE UI.
These IP addresses will not change so long as your ASE stays up and running. If your ASE becomes suspended and restored, the addresses used by your ASE will change. The normal cause for an ASE to become suspended is if you block inbound management access or block access to an ASE dependency.
I have a website on Azure App service and I've asked a service provider to open up for my outbound IP addresses. How can I make sure that those IPs won't change?
If there is a new IP assigned to my app service, all calls from that IP will be blocked by the service provider.
The outbound IP addresses are per stamp/scale unit that the apps are on. It is not specific to a certain webspace or resource group.
You can find the stamp/scale unit in the Properties blade under the FTP Hostname endpoint. It should list out something like "waws-prod--". All of the apps in the same stamp/scale unit number in that region will have the same outbound IP addresses, as they are per stamp/scale unit.
The list of outbound IP addresses is not completely static but normally it does not change. Check out the reasons for the IP change in the thread outlined by Ruslan.
If you need both incoming and outgoing to be static, you will need an App Service Environment. This will give you dedicated IP addresses.
For more information see: https://learn.microsoft.com/en-us/azure/app-service/environment/app-service-app-service-environment-intro and https://msdn.microsoft.com/en-us/magazine/mt793270.aspx.