We have an Azure WebJob running on an App Service connected to a vNET via Point-to-Site connection.
That same vNET is then connected to the on-premise network via a Site-to-Site VPN connection.
Routing is set up so to the Site-to-Site conn so that that the IP range of the Azure vNET (172.27.0.0/24) is sent from OnPrem > Azure. This can be tested by logging in to a VM inside of the vNET to query on premise resources - this works fine, and as expected.
If the same request (to a REST API) is sent from the WebJob, things do not work.
The IP range of the Point-to-Site (172.27.1.144/28) does not intersect with that of the vNET, so i am wondering if we need to also route this range "back across" the Site-to-Site connection also?
Another alternative is that a routing table within Azure needs to have a manual entry, somehow?
Any tips on how to troubleshoot / get this working would be much appreciated.
The IP range of the Point-to-Site (172.27.1.144/28) does not intersect
with that of the vNET, so i am wondering if we need to also route this
range "back across" the Site-to-Site connection also?
You need to do that, indeed. Not only that, you need to configure this network range (172.27.1.144/28) on your on-premises router too - so it recognises and accepts the traffic.
But in order to make the routing from the Point-to-Site (Azure app service) to the on-premise over the Site-to-Site VPN Connection, you will need to use a Virtual Appliance which is capable of forwarding the traffic.
For sake of simplicity and cost savings, you could just use Azure Hybrid Connections to connect Azure Web App / Web Job to on-premise Resource.
You can also refer to the documentation here, which lists the limitations of connecting App Service Plan to a Virtual Network, namely:
There are some things that VNET Integration does not support
including:
mounting a drive
AD integration
NetBios
private site access
Please note the last one - private site access - this is your on-premises.
Related
I deploy my web application to an App Service instance on Premium tier. My web application makes outbound requests to external resources on the Internet.
In order to secure the connection with one of these external resources so I can reach it with a private IP address, my plan is to create a Site-to-Site VPN from Azure to Oracle Cloud Infrastructure (where the external resource resides). Then, I plan to use the VNET Integration for outbound traffic and connect my App Service to my VPN.
My question is - will the web application still be able to reach the other external resources on the Internet with their public IPs? I believe the answer is related to routing tables but I can't wrap my mind around it.
Just because you integrate a Regional VNet (I'm assuming) doesn't mean the app service won't be able to make outbound connections. Pretty much like
When you integrate your app service with your VNet that has the site-to-site VPN, traffic from your app service will traverse the Azure network rather than going out to internet, assuming your app service is using an RFC1918 address for your infrastructure. If you want to secure the traffic even further, then your app service would need to be hosted inside an App Service Environment
We have set up a VPN gateway and used it to connect an on-premise network with an Azure VNet. We have successfully tested a number of scenarios
communication from VMs to on-premise DBs
communication from on-premise computers (desktops and servers) to VMs (SSH etc.)
communication from on-premise computers (desktops and servers) to services with Private Link endpoints (App Serivces, DBs etc.).
The use-case we are now attempting is to access an on-premise DB from an app-service. I have integrated the app-service to the routed VNet and also added a service endpoint to this VNet. I have seen infos that this should work but it is not getting though.
A second question is what is the actual source ip of the app-service when it connects to the on-premise server. Surely not the outbound IPs? These are non-exclusive public IPs. Opening these on our VPN firewall would be a risk. In this case is the solution to also give the app service in question a private link endpoint. Will it's source IP then be the private IP of the PL?
Private Endpoint is only used for incoming flows to your Web App. Outgoing flows will not use this Private Endpoint, but you can inject outgoing flows to your network in a different subnet through the VNet integration feature. When you enable Private Endpoint to your Web App, the access restrictions configuration of the Web App is not evaluated. So in this case, I don't think you need to set the service endpoint Microsoft.Web for your web app if you have set it. Reference from using Azure private endpoint for Azure web app.
When regional VNet Integration is enabled, your app makes outbound calls to the internet through the outbound addresses that are listed in the app properties portal. Regional VNet Integration works by mounting virtual interfaces with addresses in the delegated subnet. If WEBSITE_VNET_ROUTE_ALL is set to 1, all outbound traffic can be sent into your VNet. So the source IP address will be from the integrated subnet when app service comes to the on-premise server as the #silent's comment. Reference from how regional VNet Integration works. Please note that the feature supports only one regional VNet Integration per App Service plan.
I've got an Azure app service that I'd like to use to run some software that requires licensing. The license is provided via a server on our internal network. The issue being finding a way to connect to this server.
The first option is to provide a fixed license that ties to the MAC address. However I don't think this will be possible from an app service, as it does not really have a MAC address? Can I provide a VNI to it and obtain a fixed MAC address that way?
What other options are there? Can the app service be tied to a VNET that can tunnel to the on-premises resource? Should I use a VM with a VNI instead of an app service? Any resources on these kind of problems would be appreciated.
I have used Azure Relay to connect my on-prem service with my app service. Not sure if you have already considered this option.
If your requirement is to establish a connection between your on-prem service and you app service, check out this https://learn.microsoft.com/en-us/azure/service-bus-relay/relay-what-is-it
Hope this helps
You could use VNet Integration with Azure App service and Azure VPN gateway to connect to on-premise resources. VNet Integration is used only to make outbound calls from your app into your VNet. There are Regional VNet Integration and Gateway-required VNet Integration.
How regional VNet Integration works
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.
How gateway-required VNet Integration works
Gateway-required VNet Integration is built on top of point-to-site VPN
technology. Point-to-site VPNs limit network access to the virtual
machine that hosts the app. Apps are restricted to send traffic out to
the internet only through Hybrid Connections or through VNet
Integration. When your app is configured with the portal to use
gateway-required VNet Integration, a complex negotiation is managed on
your behalf to create and assign certificates on the gateway and the
application side. The result is that the workers used to host your
apps are able to directly connect to the virtual network gateway in
the selected VNet.
For more information, you could read this blog---How to Connect Azure Web Apps To On-Premises
In addition, If you need more control of the application deployment and less scale out or in than the Azure app service. You could host your application on the Azure VM, then set up a VPN gateway in that VNet where Azure VM locate, it allows access to the on-premise resources from your Azure VM as usual in the internal network.
I've been trying to set up an App Service which communicates with a server in our on-premises environment. I've set up everything regarding VNET, Local network gateway, Virtual network gateway, Point-to-Site and so on. I've also set up a Linux VM to enable testing, the VM can communicate with on-prem and on-prem reaches our VM.
I also connected the app service to the VNET and it is able to tcpping the VM. But I can't get the app service to communicate with the on-prem service.
In the App Service Plan everything looks normal, I can see all the subnets, site-to-site, point-to-site and that the certificates are in sync.
But when I look at the Networking for the App Service it does not show as connected and Azure says that the certificates are not in sync. Could this be one of the reasons why the App Service and the on-prem can't communicate? Do I have to add routes for the Point-to-Site to the on-prem network?
If the Networking for the App Service is working well it should show as connected and the certificates are in sync. One or more of the possible actions you could try:
Avoid picking IP address space that overlaps with other networks.
When the Site to Site VPN is first set up then the scripts used to configure it should set up routes including your Point-to-Site VPN. If you add the Point-to-Site VPN after you create your Site to Site VPN, then you need to update the routes manually.
If those certificates or network information is changed, then you need to click Sync Network to forcibly sync the certificate to ensure the security of the connection. NOTE: When you click Sync Network then you cause a brief outage in connectivity between your app and your VNet. While your app is not restarted, the loss of connectivity could cause your site to not function properly.
You can get more details from the VNet Integrations.
Update
If your VNet hosted VM can reach your on-premises system but your app can't then the reason is likely one of the following:
your routes are not configured with your point to site IP ranges in your on-premises gateway
your network security groups are blocking access for your Point-to-Site IP range
your on-premises firewalls are blocking traffic from your Point-to-Site IP range
you have a User Defined Route(UDR) in your VNet that prevents your Point-to-Site based traffic from reaching your on-premises network
I'm trying to setup a VPN connection from a VLAN in Azure to on-premise. We have two different ISP's on-premise and I want to setup Azure with a VPN connecting to both so that if the primary ISP is down Azure will try to connect using the secondary.
The problem is that I can't add two gateways to a single VLAN, and the one gateway will not let me add two VPN connection with the same IP address range. I can understand that if I wanted both to be active, but I want one to be standby and only used if the first disconnects.
Is this even possible? Any pointers would be great?
I have been looking at https://learn.microsoft.com/en-us/azure/vpn-gateway/vpn-gateway-highlyavailable#a-name--activeactiveonpremamultiple-on-premises-vpn-devices but that only covers active-active setup which is not what I want.
I want both VNET resouces and on-premise resources to reach each other via the same IP addresses no matter if it's the primary or secondary VPN that's connected.
I know that Azure has fail over on it's side via a standby gateway, but I want fail over when on-premise is down, not Azure.
Update
I know that Azure has fail over on it's side via a standby gateway,
but I want fail over when on-premise is down, not Azure.
Unfortunately, there is not an auto solution for on-premise failover, you could manually perform, which is the same as If the on-premises gateway IP change need to update the same entry. You need to update the local network gateway (Including the On-premises gateway IP and private range ) on the Azure side and the ISP settings where VPN is connected on the on-premise side. Please expect some downtime, because IPSEC session of ISAKMP, PH1 and PH2 Will again take place.
Besides, If you have more than one ISP and need a redundant connection to the Azure. Azure now supports redundant Site to Site VPNs.
Support multiple tunnels between a VNet and an on-premises site with automatic failover based on BGP
You can establish multiple connections between your Azure VNet and
your on-premises VPN devices in the same location. This capability
provides multiple tunnels (paths) between the two networks in an
active-active configuration. If one of the tunnels is disconnected,
the corresponding routes will be withdrawn via BGP and the traffic
automatically shifts to the remaining tunnels.
The following diagram shows a simple example of this highly available setup:
NOTE
BGP is supported on Azure VpnGw1, VpnGw2, VpnGw3, Standard and HighPerformance VPN gateways. Basic SKU is NOT supported.
BGP is supported on Route-Based VPN gateways only.