virtual network
243 TopicsA demonstration of Virtual Network TAP
Azure Virtual Network Terminal Access Point (VTAP), at the time of writing in April 2026 in public preview in select regions, copies network traffic from source Virtual Machines to a collector or traffic analytics tool, running as a Network Virtual Appliance (NVA). VTAP creates a full copy of all traffic sent and received by Virtual Machine Network Interface Card(s) (NICs) designated as VTAP source(s). This includes packet payload content - in contrast to VNET Flow Logs, which only collect traffic meta data. Traffic collectors and analytics tools are 3rd party partner products, available from the Azure Marketplace, amongst which are the major Network Detection and Response solutions. VTAP is an agentless, cloud-native traffic tap at the Azure network infrastructure level. It is entirely out-of-band; it has no impact on the source VM's network performance and the source VM is unaware of the tap. Tapped traffic is VXLAN-encapsulated and delivered to the collector NVA, in the same VNET as the source VMs, or in a peered VNET. This post demonstrates the basic functionality of VTAP: copying traffic into and out of a source VM, to a destination VM. The demo consists of 3 three Windows VMs in one VNET, each running a basic web server that responds with the VM's name. Another VNET contains the target - a Windows VM on which Wireshark is installed, to inspect traffic forwarded by VTAP. This demo does not use 3rd party VTAP partner solutions from the Marketplace. The lab for this demonstration is available on Github: Virtual Network TAP. The VTAP resource is configured with the target VM's NIC as the destination. All traffic captured from sources is VXLAN-encapsulated and sent to the destination on UDP port 4789 (this cannot be changed). We use a single source to easier inspect the traffic flows in Wireshark; we will see that communication from the other VMs to our source VM is captured and copied to the destination. In a real world scenario, multiple or all of the VMs in an environment could be set up as TAP sources. The source VM, vm1, generates traffic through a script that continuously polls vm2 and vm3 on http://10.0.2.5 and http://10.0.2.6, and https://ipconfig.io. On the destination VM, we use Wireshark to observe captured traffic. The filter on UDP port 4789 causes Wireshark to only capture the VXLAN encapsulated traffic forwarded by VTAP. Wireshark automatically decodes VXLAN and displays the actual traffic to and from vm1, which is set up as the (only) VTAP source. Wireshark's capture panel shows the decapsulated TCP and HTTP exchanges, including the TCP handshake, between vm1 and the other VMs, and https://ipconfig.io. Expanding the lines in the detail panel below the capture panel shows the details of the VXLAN encapsulation. The outer IP packets, encapsulating the VXLAN frames in UDP, originate from the source VM's IP address, 10.0.2.4, and have the target VM's address, 10.1.1.4, as the destination. The VXLAN frames contain all the details of the original Ethernet frames sent from and received by the source VM, and the IP packets within those. The Wireshark trace shows the full exchange between vm1 and the destinations it speaks with. This brief demonstration uses Wireshark to simply visualize the operation of VTAP. The partner solutions available from the Azure Marketplace operate on the captured traffic to implement their specific functionality.214Views0likes1CommentConsistent DNS resolution in a hybrid hub spoke network topology
DNS is one of the most essential networking services, next to IP routing. A modern hybrid cloud network may have various sources of DNS: Azure Private DNS Zones, public DNS, domain controllers, etc. Some organizations may also prefer to route their public Internet DNS queries through a specific DNS provider. Therefore, it is crucial to ensure consistent DNS resolution across the whole (hybrid) network. This article describes how DNS Private Resolver can be leveraged to build such architecture.18KViews5likes5CommentsCustom DHCP support in Azure
Discover the intricacies of Dynamic Host Configuration Protocol (DHCP), a network protocol used for assigning IP addresses and network parameters. Learn about the DORA process, lease renewals, and the role of DHCP Relay in large enterprises. Gain insight into how DHCP operates in Azure natively and how its support in Azure has evolved over time, including the removal of rate-limiting for relayed traffic. This comprehensive guide also covers the limitations and potential workarounds of DHCP in Azure. Ideal for network administrators and IT professionals.18KViews15likes4CommentsHelp! - How is VNet traffic reaching vWAN/on‑prem when the VNet isn’t connected to the vWAN hub
Hello, I needed some clarity on how the following is working: Attached is a network diagram of our current setup. The function apps (in VNet-1) initiate a connection(s) to a specific IP:Port or FQDN:Port in the on-premises network(s). A Private DNS zone ensures that any FQDN is resolved to the correct internal IP address of the on-prem endpoint. In our setup, both the function app and the external firewall reside in the same VNet. This firewall is described as “Unattached” because it is not the built-in firewall of a secured vWAN hub, but rather an independent Azure Firewall deployed in that VNet. The VNet has a user-defined default route (0.0.0.0/0) directing all outbound traffic to the firewall’s IP. The firewall then filters the traffic, allowing only traffic destined to whitelisted on-premises IP: Port or FQDN: Port combinations (using IP Groups), and blocking everything else. The critical question and the part that I am unable to figure out is: Once the firewall permits a packet, how does Azure know to route it to the vWAN hub and on to the site-to-site VPN? Because VNet-1 truly has no connection at all to the vWAN hub (no direct attachment, no peering, no VPN from the NVA). But the traffic is still reaching the on-prem sites. Unable to figure out how this is happening. Am I missing something obvious? Any help on this would be appreciated. Thank you!145Views0likes3CommentsTraffic processing BGP Azure VPN gateway A/A
Hello, Can someone explain how Azure processes the traffic with implemented a VPN gateway in Active Active mode?. Azure firewall premium is also configured. BGP is without preferences. The user route definition is set up to the next hop Azure firewall . Is it possible in this scenario occurs the asymmetric routing with traffic drop by azure firewall ? In my understand is that, if we need to configure User route definition on Gateway subnet to inspect traffic to peering subnet, so the firewall don't see traffic passing through VPN gateway. Traffic going through ipsec tunnels can go different paths and firewall do not interfere because everything is routed to it by user route definition.91Views0likes1CommentHelp ! - Hub Spoke Architecture and Routing via NVA
I have a classic example of routing. I want to force all traffic via Fortigate firewalls. EastWest and NorthSouth. However when large Supernet of Azure Vnet is used to route and force the traffic via UDR at gateway subnet, its not working. Because Routes learned at Hub Vnet via Vnet peering is taking precedence. To isolate, i have created multiple small subnet routes for Gateway subnet. Each pointing to spoke vnet and next hop as Fortigate firewall. However this is working, i want to make solution solid. Means if someone creates new vnet in future and peer with Hub, it should not get direct traffic. Is that possible? Or this is typical shortcoming of Azure where routing works with preference to vnet peeering.? Below is architecture -Solved200Views0likes2CommentsAdvanced Container Apps Networking: VNet Integration and Centralized Firewall Traffic Logging
Azure community, I recently documented a networking scenario relevant to Azure Container Apps environments where you need to control and inspect application traffic using a third-party network virtual appliance. The article walks through a practical deployment pattern: • Integrate your Azure Container Apps environment with a Virtual Network. • Configure user-defined routes (UDRs) so that traffic from your container workloads is directed toward a firewall appliance before reaching external networks or backend services. • Verify actual traffic paths using firewall logs to confirm that routing policies are effective. This pattern is helpful for organizations that must enforce advanced filtering, logging, or compliance checks on container egress/ingress traffic, going beyond what native Azure networking controls provide. It also complements Azure Firewall and NSG controls by introducing a dedicated next-generation firewall within your VNet. If you’re working with network control, security perimeters, or hybrid network architectures involving containerized workloads on Azure, you might find it useful. Read the full article on my blog100Views0likes0CommentsNetwork Detection and Response (NDR) in Financial Services
New PCI DSS v4.0.1 requirements heighten the need for automated monitoring and analysis of security logs. Network Detection and Response solutions fulfill these mandates by providing 24/7 network traffic inspection and real-time alerting on suspicious activities. Azure’s native tools (Azure vTAP for full packets, VNET Flow Logs for all flows) capture rich network data and integrate with advanced NDR analytics from partners. This combination detects intrusions (satisfying IDS requirements under Requirement 11), validates network segmentation (for scope reduction under Req. 1), and feeds alerts into Microsoft Sentinel for rapid response (fulfilling incident response obligations in Req. 12). The result is a cloud architecture that not only meets PCI DSS controls but actively strengthens security.1.2KViews1like0CommentsIKEv2 and Windows 10/11 drops connectivity but stays connected in Windows
I’ve seen this with 2 different customers using IKEv2 User VPNs (virtual wan) and Point to Site gateways in hub and spoke whereby using the VPN in a Always On configuration (device and user tunnel) that after a specific amount of time (56 minutes) the IKEv2 connection will drop the tunnel but stay connected in Windows. To restore the connection, you just reconnect. has anyone else had a similar experience? I’ve seen the issue with ExpressRoute and with/without Azure firewalls in the topology too.1.5KViews0likes1CommentHow can I convert an website on Microsoft to IOS?
Hello everyone, Hope you all are doing good, I am Jeck. I have a website which I design and developed on my apple machine and basically made on IOS. Now, I want to change my website to Microsoft, my website is on https://www.bestelectricsmoker2021.com/ Can you guide me porperly or suggest me anyone who can work for me and extend my bussiness on Micosoft. Thank you Have a good day!683Views0likes1Comment