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You have an Azure subscription that contains the following resources:
✑ A virtual network that has a subnet named Subnet1
✑ Two network security groups (NSGs) named NSG-VM1 and NSG-Subnet1
✑ A virtual machine named VM1 that has the required Windows Server configurations to allow Remote Desktop connections
NSG-Subnet1 has the default inbound security rules only.
NSG-VM1 has the default inbound security rules and the following custom inbound security rule:
✑ Priority: 100
✑ Source: Any
✑ Source port range: *
✑ Destination: *
✑ Destination port range: 3389
✑ Protocol: UDP
✑ Action: Allow
VM1 connects to Subnet1. NSG1-VM1 is associated to the network interface of VM1. NSG-Subnet1 is associated to Subnet1.
You need to be able to establish Remote Desktop connections from the internet to VM1.
Solution: You add an inbound security rule to NSG-Subnet1 that allows connections from the Internet source to the VirtualNetwork destination for port range 3389 and uses the UDP protocol.
Does this meet the goal?
A . Yes
B . No
Answer: B
Explanation:
The default port for RDP is TCP port 3389 not UDP.
NSGs deny all inbound traffic except from virtual network or load balancers. For inbound traffic, Azure processes the rules in a network security group associated to a subnet first, and then the rules in a network security group associated to the network interface.
By default NSG rule to allow traffic through RDP port 3389 is not created automatically during the creation of VM, unless you change the setting during creation.
Here in the solution UDP traffic is allowed at virtual network level which is not tcp/rdp protocol. So this will not work to achieve the goal.
References:
https://docs.microsoft.com/en-us/azure/virtual-machines/troubleshooting/troubleshoot-rdp-connection
https://docs.microsoft.com/en-us/azure/virtual-network/security-overview#default-security-rules
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