Azure Multi-Site VPN from One Location - azure

We have a client who wants to connect their premises to Azure. Their main hindrance at this point is determining the best way to connect to Azure given their current connectivity configuration. They have two redundant ISP connections going to the head office for internet access. They want to be able to configure a VPN connection to Azure that would operate in a similar way i.e. if ISP A went down it would seamlessly use ISP B and vice versa. The normal multi-site VPN configuration does not fit this since there is one local network behind which means the network behind separate VPNs over each ISP would have overlapping IP address ranges which is not supported. Is such a configuration possible? (See diagram below)
Either that or is there a way to abstract the two ISP connections onto one VPN connection to Azure.
They’re currently considering using a Cisco ASA device to help with this. I’m not familiar with the features of this device so I cannot verify if it will solve their issue. I know there is also a Cisco ASAv appliance in the Azure marketplace don't know if that could also be a part of a possible solution if they went with such a device.
required vpn configuration

The Site-to-Site VPN capability in Azure does not allow for automatic failover between ISPs.
What you could do are the following
- Have automation task created that would re-create the local network and gateway connection upon failover. Manual and would take some RTO to get it up and running
- Use the Cisco CSRs to create a DMVPN mesh. You should be able to achieve the configuration you want using that option. You would use UDRs in Azure to ensure proper routing

I havent done it in Azure, but here is what you do in AWS (And I am sure there would be parallel in Azure)
Configure a "detached VGW" (virtual Private gateway) in aws. Use DMVPN cloud to connect CSRs to multi-site on-prem.
Also, for failover between ISPs you could have a look at DNS load balancing via a parallel to AWS's Route 53 in Azure.
Reference thread :
https://serverfault.com/questions/872700/vpc-transit-difference-between-detached-vgw-and-direct-ipsec-connection-csr100

Related

Azure Networking - Application GW, Virtual Network GW, VWAN, ExpressRotue, PrivateLink, Arc

can anyone explain difference between Azure Application Gateway, Virtual Network Gateway, Virtual WAN, ExpressRoute, Arc and Private Link, please?
It seems to me all services are pretty similar helping with connecting either on-prem to Azure, in-Azure to in-Azure or public to Azure.
They're similar in that they all involve network traffic, but that's pretty much where the similarities end.
Application Gateway is a Layer 7 load balancing service with advanced features like SSL termination. It's used to route client requests to your applications.
Virtual Network Gateway is a VPN gateway for point-to-site (user) and site-to-site (office/datacenter) VPN connections to your own Azure VNETs. This would, for example, allow you to RDP into Azure VMs from your on-prem office using their private IPs.
ExpressRoute is similar to site-to-site, however it doesn't use IpSec tunnels, it's a dedicated, unencrypted connection from your location directly into Microsoft's backbone. (i.e. you don't traverse the public internet). There's no encryption and the connection is faster. This is a service you need to work with a 3rd party internet provider to implement.
Virtual WAN is more like a networking hub where there would be many site-to-site, point-to-site, ExpressRoute, etc... connections spanning a wide area (as the name implies). This would be for large enterpise organizations with many on-prem locations.
Arc is a means of adding your on-prem resources into Azure for management. e.g. you have a physical server somewhere and you want to manage it though ARM/portal.
Azure Private Link is a feature of many Azure services (storage, SQL PaaS, etc..) which allows you to create a private DNS record and assign a private IP address on your internal VNETs. This is used when you want to disable all public network access to a resource and only allow access from within your own VNET.
I have barely scratched the surface of the differences here, but suffice it to say, there are many differences. From this page, you can type the service name into the search and get more specific details on the offering. Hope this helps.
https://learn.microsoft.com/en-us/search/?terms=networking%20in%20azure

Is it possible for a Azure Container App to access on-prem network share using a UNC path?

Hey all I've been trying to look into whether this is possible or not.
I was working with Infra-Engineering to setup a VNet with peering to the on-prem network. Everything was smooth sailing until we found out that the Azure Sandbox for Function Apps blocks the SMB ports. I saw a reply on this thread: https://learn.microsoft.com/en-us/answers/questions/290531/how-can-i-access-a-on-premise-network-file-share-d.html
that if we use a Container App that we would not have this restriction. Can anyone corroborate this? I just want to get some insight before committing to trying this out.
In short - you need a VPN/Express Route connection to on premise, the container app needs to be in a VNet peered with the VPN VNet (if separated), a DNS server able to resolve on-premises DNS records, if there are firewalls, NSGs involved you will also need access rules there, and obviously the IP address ranges need to be routed (BGP or Static) and should not overlap
https://techcommunity.microsoft.com/t5/apps-on-azure-blog/azure-container-apps-virtual-network-integration/ba-p/3096932
https://learn.microsoft.com/en-us/azure/architecture/hybrid/hybrid-dns-infra

How do we use Azure Analysis Service with the SQL databases that are behind the firewall?

We are considering using Azure Analysis Services for the BI requirements. Currently, the databases are deployed behind a firewall in a VNET. Since AAS do not have either VNET support or has static IP address range, how do we connect to the databases behind the firewall? I have seen one solution where folks are talking about using the gateway (https://azure.microsoft.com/en-gb/blog/azure-analysis-services-integration-with-azure-virtual-networks-vnets/). But apart from using Gateway, what are the other options I have?
You need to
Install On-Premises Data Gateway on VM
Add VM Virtual Network to SQL firewall settings
Set AAS to use On-Premises Data Gateway
Force all AAS traffic through gatway. This is important.
As for other options I don't think there are any that are good in terms of security. AAS IP can change during restarts so you can't make it this way. Unless you write script which changes IP every time but its cumbersome.
At this time gateway is our current production solution for this scenario.
For dev/test you can always examine the connection failure error from AAS to SQL Database, extract the IP address and add a firewall exception for that IP address, or a small range containing it.

Best network design for company with remote offices that need to go through 1 public facing interface

I received a call from a business owner. One of his services will only license and whitelist one public IP well he has three locations. When I got involved they were trying to spin up an OpenVPN appliance and have site to site vpns to the remote locations. Well the remote locations have Fortigate firewalls and this will not work I believe with the SSL VPN of OpenVPN.
I would like to recommend something with Azure or AWS but I am unclear on the best VPN setup with Azure. Essentially he will need all remote sites exiting to the internet through Azure.
Late last night tried to test with AWS VPC and a VPN back to the fortigate. Client later expressed he would rather not use AWS.
Also recommended this https://forum.fortinet.com/m/tm.aspx?m=148626&p=
but he did not want to bottlekneck one of his locations
All sites exiting Azure out of one IP address
If you have 3 sites in Azure, you can make all 3 sites exiting Azure with one VPN gateway IP for the same destination.
You need to configure VNET to VNET peering and enable Gateway Transit to make it work. Can you also elaborate your ask here with a Network Diagram ?

Q: Azure S2S VNet VPN with failover

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.

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