Sorry if this is vague...I am currently looking at an AZURE architecture design that has 3 VNETs. I am looking for each VNET pass through a firewall server.
Basically I am trying to figure out if 1VM can be part of 3 Virtual networks without multiple NICs, or if AZURE doesn't support this function yet at all.
A VM can be a part of three subnets in a single network, if you have three nics. So at the minimum you would need an A4/extra large which has a 4 nic capacity.
You could then link the vnets together to create a logical grouping.
But it is not possible to have a single VM in multiple VNets.
Related
I am working on an Azure-based networking solution.
We have a typical hub and spoke VNets topology. The Hub VNet connects to on-prem DC via ExpressRoute and spoke VNets peer to Hub VNet. There is an Azure Firewall in the Hub that filters traffic between Hub-spokes and hub-on-prem segments. GREEN in the diagram
We have a bizarre requirement of adding a new isolated VNet (RED in the diagram) that will have overlapping IPs with the existing network (GREEN). We want to allow workloads in this new VNet to access private apps deployed in Hub or on-prem.
I need help on how to achieve this connectivity.
Note: We don't want to set up any VPN between the new VNet and Hub
As you might appreciate, this is more of a general networking limitation moreso than an Azure limitation. If we want two different networks with overlapping IP addresses to communicate then we would need networking devices in between both networks that perform some form of network address translation so the IP addresses appear to be different to the communicating hosts. Below is an example from the Azure documentation
Logically you have two options here:
Create your own network devices and configure routes between these subnets to transit your virtual appliance that does the translation.
Use the managed service from Azure. In this case, it's the Azure VPN Gateway
I saw your note above for not wanting to use any VPN devices. Having said that, however, generally speaking it is usually a better option from an availability & supportability perspective to leverage the built-in offering vs. hand rolling your own virtual appliance using IP tables or a Windows NAT Router or something similar. Hope this clarifies.
It is not possible to peer Virtual Networks with overlapping IP addresses. This is documented here. You will have to move to a different address space and move/recreate resources under this new address space.
If it helps you can take a look at this Checklist before moving resources.
if someone can give me a industry example on why do we need multiple Virtual Networks and Subnets?
One vnet cannot span subscriptions or regions. So everytime you need services deployed in to vnets in different subscriptions or in different regions you would need multiple vnets.
Multiple subnets are often used to separate workloads for security reasons. Making sure services on different subnets cannot communicate with eachother or only communicate over controlled ports.
Can someone let me know when Microsoft Azure introduced Vnet Peering? I'm working with a company that has introduced a number of Vnets (8 Vnets) for security. I'm trying to suggest that creating that number of Vnets is unnecessary.
I just would like to know if there are any other benefits to Vnet peering and when it was first introduced by Azure?
Cheers
Carlton
I just would like to know if there are any other benefits to Vnet
peering and when it was first introduced by Azure?
Virtual network peering enables you to connect two virtual networks in the same region through the Azure backbone network. Once peered, the two virtual networks appear as one, for connectivity purposes. The two virtual networks are still managed as separate resources, but virtual machines in the peered virtual networks can communicate with each other directly, by using private IP addresses. More information about this please refer to this link.
I'm trying to suggest that creating that number of Vnets is
unnecessary.
It depends on your company's need. If you want to connect two Vnets, you must create a peering tunnel.
VNet peering is between two virtual networks, and there is no derived transitive relationship.
In others words, if you want 3 VNets to be both interconnected, you need create 3 peering tunnels. Please refer to the similar question.
We announced peering in September 2016. See our service update for reference: https://azure.microsoft.com/en-us/updates/vnet-peering-ga/
VNet peering has many benefits: low latency, high bandwidth, direct VM to VM connectivity among others. You can see a comprehensive list here: https://learn.microsoft.com/en-us/azure/virtual-network/virtual-network-peering-overview
You can also suggest using subnets in the same virtual network: https://learn.microsoft.com/en-us/azure/virtual-network/virtual-networks-create-vnet-arm-pportal
-- Anavi N [MSFT]
I have 2 Virtual Networks and each of them has a subnet. I want to assign 2 private IP's to a virtual machine. One private IP resides in 1st Virtual Network while second private IP is in 2nd Virtual Network.
I have tried attaching 2 NIC's to the VM, and attached the first private IP to first NIC and second private IP to second NIC.
When I deploy the ARM template it says that second NIC is referring to a subnet which is not in same Virtual Network?
How can I achieve this in Azure?
How can I achieve this in Azure ?
As far as I know, Azure does not support this.
For now, Azure just support multiple NICs on the same virtual network.
Q:Are there any limitations to this feature that customers must be aware
of?
A:Multiple NIC is supported on Azure VMs (IaaS, Standard SKUs) only;
and VMs must be in an Azure Virtual Network.
More information about multiple NICs, please refer to this link.
Select the existing NIC for the box you are trying to assign the second Private IP,
Select IP configuration on the right tab bar,
Click on +Add, write a name for your new IP address,
Select static Private IP address (it could stay as dynamic as well)
I think your best bet would be Azure VNET Peering, which can loosely be thought of as a VPN between the two VNETs via the Azure backbone. This way, all machines in one VNET can talk directly to all those in the second VNET. It assumes that there's no Address Space crossover between the to VNETs, but if that's the case you may always have struggled.
There's a good article here which explains it in more detail.
The best scenario to implement this through below steps.
Site 2 site between the 2 VNET thru VPN gateway.
Also you have to make the machines in Fail over cluster so as they form a cluster.
I have two kind of services deployed on Azure, and they need communicate with each other. So far two options:
1. Put them in same Vnet
2. Put them in separate Vnet and create Vnet-to-Vnet connection between them.
My question is, is there any performance/bandwidth limitation on option 2 compared to option 1?
I would say approach 1 is better in case you have less load in your vNet.
In Approach 2 the communication depends on below factors-
1. Whether the two vNets are in same region or not. If yes obviously you will face less latency.
2. Which vNet gateway you have selected- high performance vNet gateway provides faster speed over basic and standard.
Azure point to site vpn connections are reliable only when the data to be transferred is not much ( < 1Tb ) and are in the same region.
Also consider that with option 2 you will face egress data charges for traffic exiting the VNET.
If you're workloads are similar or are even in two separate tiers (web vs app vs data for example), you can segregate them via subnet and NSG. You don't need to separate out into different VNETs.