Troubleshooting VPN Connectivity

Correct Answer: C.

In the above question, source IP 172.31.41.189 tries to do an RDP session (destination port 3389) to destination IP address 172.8.51.117 using TCP protocol ( Protocol number 6).

VPC Flow Logs have the following fields.

Version: 10

Account-id: 123456789010

Interface-id: eni-abc123de.

Source IP: 172.31.41.189

Destination IP: 172.8.51.117

Source Port: 39751

Destination Port: 3389

Protocol: 6

Packets:20

Bytes: 3279

Start Time:1218430010

End Time:1218430070

Action: REJECT.

Log-status: OK.

Option A is incorrect as VPC Logs has a protocol number 6 which is a TCP Protocol number & not a UDP packet that has a Protocol number 17.

Option B is incorrect as VPC logs source IP address is 172.31.41.189 while destination IP address is 172.8.51.117.

Option D is incorrect as VPC Logs has a protocol number 6 which is a TCP Protocol number & not a UDP which has a Protocol number 17

Also, the source IP address is 172.31.41.189 while the destination IP address is 172.8.51.117.

For more information on VPC Flow Logs, refer to the following URL-

https://docs.aws.amazon.com/vpc/latest/userguide/flow-logs.html

The VPC flow log record captured is as follows:

yamlCopy code
10 123456789010 eni-abc123de 172.31.41.189 172.8.51.117 39751 3389 6 20 3279 1218430010 1218430070 REJECT OK 

Each field in the VPC flow log record represents the following information:

1. 10 - The version number of the VPC Flow Logs format.
2. 123456789010 - The AWS account ID.
3. eni-abc123de - The network interface ID.
4. 172.31.41.189 - The source IP address.
5. 172.8.51.117 - The destination IP address.
6. 39751 - The source port number.
7. 3389 - The destination port number.
8. 6 - The protocol number.
9. 20 - The number of packets transmitted from the source to the destination.
10. 3279 - The number of bytes transmitted from the source to the destination.
11. 1218430010 - The start time of the flow, in Unix epoch time.
12. 1218430070 - The end time of the flow, in Unix epoch time.
13. REJECT - The action taken on the traffic.
14. OK - The reason for the action taken on the traffic.

From the above information, we can infer the following:

• The source IP address is 172.31.41.189.
• The destination IP address is 172.8.51.117.
• The source port number is 39751.
• The destination port number is 3389.
• The protocol number is 6, which corresponds to TCP.

Therefore, the correct answer is option C: Host with IP 172.31.41.189 is trying RDP connection using TCP protocol to host with IP 172.8.51.117.