I am using same NSG for two subnets in a VM. Now i have created a Custom rule where VM1 cannot accept packets from VM2. But default NSG rule allows VM2 to send packets to VM1.
Here are the pictures - Vm2 to Vm1 outbound default rule created by NSG
Vm1 custom inbound rule set by me
Does VM2 communicate with VM1 or can VM1 receive packets from VM2?
As your screenshot displayed, VM2 can send packages to VM1 but VM1 can not receive packages from VM2 because the inbound traffic from VM2 is blocked.
For a short test. VM1 is VMb and VM2 is VMc in my example.
The NSG setting of both subnets
From VMb to VMC
From VMC to VMb
Related
I have the following subnets
Subnet_1 = 10.2.3.0
Subnet_1 = 10.2.4.0
I want to prevent subnet to subnet communication. As far as I see, it can be done using the Network Security Group. However I am not sure about the required change.
I tried to reproduce the same in my environment to prevent communication between 2 Subnet
I have created 2 subnets in my Vnet, like below.
Subnet 1: Prod-Subnet (10.0.1.0/24)
Subnet 2: default (10.0.0.0/24)
In order to prevent communication between both the VNet, you need to create an inbound and outbound rule in same NSG group, like below.
I have created 2 virtual machines and attached above subnets to 2 virtual machines, like below.
Prod-subnet attached to VM1
Default Subnet attached to VM2
Create inbound and outbound rule in Network Security Group to block the communicatioin ,like below.
Inbound Rule:
Source IP: 10.0.0.9/24
Source Port: * ( for all)
Destination IP: 10.0.1.0/24
Destination Port: *( for all)
Service: custom
(Note: If you want block particular service and port, mention the port details and protocol type)
Outbound Rule:
Source IP: 10.0.1.0/24
Source Port: * ( for all)
Destination IP: 10.0.0.0/24
Destination Port: *( for all)
Service: custom
Tested communication and its getting denied from the subnets.
VM 1 Result
VM 2 Result
Please below image: subnetimage
I have below things:
3 VM inside 3 subnet all are in Vnet1.
VM1 has enable IIS and it's private access through subnet B.
Is there any ways to allow traffic from VM2 to VM1? I have tried multiple time but didn't worked.
I have followed below MS Docs, but it allows only internally(private) in network, it's not working for internet.
https://learn.microsoft.com/en-us/azure/virtual-network/tutorial-create-route-table-portal
I've custom template of this scenarios, You have just apply it and all configuration will be created.
you can access from below link:
https://www87.zippyshare.com/v/bEcvSVnC/file.html
I'm new Here , Please help me out from this issue.
Update :
VM1 has assign public IP and I need all traffic from public IP of vm1 from VM2.
Please check below image for more info.
• I would suggest you to please attach one more NIC (Network Interface Card) to the VM1 in subnet A and enable IP forwarding in that NIC along with enabling the same setting in VM2 in subnet B. Since, VM2 is exposed to the internet and has a public IP address but VM1 doesn’t, thus when you configure the NSG (Network Security Group) of both the NICs, ensure that you are creating inbound as well as outbound rules for ensuring traffic flow smoothly over port 80 and 443 through both the NICs. This will ensure that internet traffic over the designated ports is only forwarded from the VM2 to the VM1 and vice versa.
• Also, if you want to, you can attach the additional NIC to VM1 and associate it in some other subnet, i.e., subnet C or any other subnet. This will ensure that the subnet level NSG in effect can be configured for the related subnets only, i.e., subnet in which the additional NIC for VM1 is added and the subnet for VM2. For more information, kindly refer to the below documentation links on attaching additional NICs to the VMs: -
https://learn.microsoft.com/en-us/azure/virtual-machines/windows/multiple-nics
https://learn.microsoft.com/en-us/azure/virtual-network/virtual-network-network-interface-vm#view-network-interfaces-for-a-vm
Snapshots for reference: -
Update : - Yes, you can surely browse the IIS page by accessing the public IP address of the VM1 in local system through chrome browser. But you will need to open the ports 80 and 443 for inbound traffic access on the VM1's NSG. Also, if you want the VM1 to have a publicly accessible DNS name/label, then you will have to configure the desired DNS name in the VM1 settings. To do the above said configurations, kindly refer to the link below: - https://social.msdn.microsoft.com/Forums/expression/en-US/98da3ab5-3909-4048-b935-95d5f7667ab5/accessing-azure-virtual-machine-iis-website-publicly?forum=WAVirtualMachinesforWindows#:~:text=1-%20Click%20on%20the%20VM,Click%20on%20Save.
Scenario
In Azure, I have the following configuration:
1 VNET (address space) - 10.10.0.0/24
Subnet 1 - 10.10.0.0/28
Subnet 2 - 10.10.0.16/28
VM 1 (in subnet 1) - has IP# of 10.10.0.1
VM 2 (in subnet 2) - has IP# of 10.10.0.17
Problem
I need to create a UDR (a custom route) that allows VM1 to receive all packets from VM2.
What would that route be?
I cannot seem to find any links on the internet explaining this scenario.
I have tested in my environment.
By default, the VM1 in subnet1 is allowed to receive all data packets from VM2 in subnet2 if both subnet1 and subnet2 are in the same Virtual Network. We do not need to create any custom route (User Defined Route) for this
For this to work, the firewall for the private networks needs to be turned off inside both the VMs. Then both the VMs will be able to receive data packets from each other
I created VM1 (10.0.0.4) in subnet1 (10.0.0.0/24) and VM2 (10.0.1.4) in subnet2 (10.0.1.0/24)
I turned the firewall off for private networks in both the VMs VM1 and VM2
I can receive data packets from each other
I pinged VM2 private IP address from VM1 and able to receive the data packets from VM2
I have added a new VM to a Subnet that has no NSG assigned to. I have a NSG where I have added rules to allow 3389 (RDP) port, but I did not associate this NSG to either the Subnet or the VM n/w interface. But still I am able to RDP into it and am also being able to reach the web server. Basically n/w traffic to port 80 and 3389 is going through.
How come this can happen, when there is no NSG assigned. Does n/w interface of the VM allow this traffic by default? If so where can I find the allowed rules and how can I restrich such a traffic?
Yes, with no NSG around nothing is being blocked (imagine NSG is a firewall, what happens when there is NO firewall?).
Attach the NSG and it will work as you expect it.
I have the following scenario.
2 vnets (same location/location, but different resource groups)
vnetA: Address space 10.1.0.0/16
Gateway subnet 10.1.1.0/24
VM 10.1.0.5
vnetB: Address space 10.0.0.0/16
Gateway subnet 10.0.2.0/24
VM 10.0.1.7
They are both peered through vnet to vnet gateways, but machines cannot ping each other.
Could anyone please guide to documentation or give advice to this please?
You should check the Network Security Groups rules associated to the VNet's Subnets or to the VM's NICs. Unfortunately there is no a specific rule for ICMP protocol, but TCP and UDP only. You have to come up with a rule that suites your needs with the 'any' protocol (i.e. '*').
Instead of using ICMP, when you want to test network connectivity I would suggest to use some TCP protocol based tool like Test-NetConnection and create proper rules in the NSG to let the network traffic pass.