Immediate Solution for Hybrid Connectivity Outages
Question
A banking organization has hybrid connectivity for its 3-tier application.
They have set up redundant AWS Direct Connect links from DataCenter to AWS.
Last week, a connectivity issue where fiber cut at the service provider end resulted in an outage of primary link & traffic was shifted to secondary after a long delay.
This resulted in the failure of many banking transactions & financial loss. After troubleshooting, it was found that traffic sent over primary link even after fiber cut & was getting blackholed.
IT head is looking for an immediate solution to this problem to avoid such instances in the future.
Which of the following solution can be deployed in a quick way?
Answers
Explanations
Click on the arrows to vote for the correct answer
A. B. C. D.Correct Answer - B.
BFD (Bidirectional forwarding detection) can be used to detect link failure & failover to secondary links faster.
BFD is enabled for all AWS DX links & is activated once BFD is configured at the Customer End router.
No additional changes are required on the AWS side for BFD configuration.
At Customer Router, BFD is enabled on a virtual interface towards AWS.
Options A & Dare incorrect as BFD needs to add on the virtual interface & not on the physical interface.
Option C is incorrect as at the AWS end, BFD is already enabled & it takes effect once BFD is configured at the Customer end router.
For more information on using BFD, refer to the following URL.
https://docs.aws.amazon.com/directconnect/latest/UserGuide/dc-ug.pdfPlease refer to the below link.
https://aws.amazon.com/premiumsupport/knowledge-center/enable-bfd-direct-connect/The scenario describes an issue with the primary AWS Direct Connect link which resulted in an outage and financial loss. The issue was caused by traffic being sent over the primary link even after a fiber cut. The IT head is looking for an immediate solution to avoid such instances in the future.
Bidirectional Forwarding Detection (BFD) is a protocol used to quickly detect failures in the forwarding path between two routers. It provides rapid detection of failures on any type of link, including physical, virtual, and logical links.
To address the issue in the scenario, BFD can be enabled at the customer end router on the physical or virtual interface. The customer can also open an AWS Support Ticket to enable BFD at the AWS end. The objective is to quickly detect any issues with the link and shift traffic to the secondary link before any financial loss occurs.
Option A suggests enabling BFD at the customer end router on the physical interface and opening an AWS Support Ticket to enable BFD at the AWS end. This solution would ensure that BFD is enabled on both ends of the link, providing a quick way to detect any issues with the link.
Option B suggests enabling BFD at the customer end router on the virtual interface. While this would provide a way to detect failures on the virtual interface, it may not detect failures on the physical interface.
Option C suggests enabling BFD at the customer end router on the virtual interface and opening an AWS Support Ticket to enable BFD at the AWS end. This would provide a way to detect failures on the virtual interface and ensure that BFD is enabled on both ends of the link.
Option D suggests enabling BFD at the customer end router on the physical interface. This would provide a way to quickly detect any issues with the physical interface, but it would not detect failures on the virtual interface.
Based on the above analysis, Option A is the best solution to deploy in a quick way to address the issue in the scenario.
