You are working as an AWS developer for an online multiplayer game start-up company. Elasticache with Redis is used for gaming leaderboards to provide low latency for online games. Redis clusters are deployed within a dedicated VPC in the us-east-1 region.
Last week, due to configuration changes in Redis Clusters, the gaming application was impacted for two hours. To avoid such incidents, you have been requested to plan for secure access to all the new clusters. What would you prefer to use for secure access to Redis Clusters while accessing from EC2 instance, initialized in different VPC in the us-east-1 region? (SELECT TWO)

Answer options:

A.Use Redis AUTH with in-transit encryption disabled for clusters.
B.Create a Transit Gateway to have connectivity between 2 VPC’s.
C.Use Redis AUTH with in-transit encryption, enabled for clusters.
D.Create an Amazon VPN connection between 2 VPCs.
E.Use Redis AUTH with At-Rest encryption, enabled for clusters.

Correct Answer – B, C
To use Redis AUTH that will require users to provide a password before accessing Redis Cluster, in-transit encryption needs to be enabled on the cluster while creating the cluster. For accessing Redis Cluster from EC2 instance in different VPCs from the same region, a Transit Gateway can be established between 2 VPCs.
Option A is incorrect. For Redis AUTH, clusters must be enabled with in-transit encryption during initial deployment.
Option B is correct. Transit Gateway is suitable to access Redis Clusters from EC2 instance in VPC created in different regions. Transit Gateway is more secure because it reduces the security footprint available between the VPCs.
Refer link: https://aws.amazon.com/transit-gateway/?whats-new-cards.sort-by=item.additionalFields.postDateTime&whats-new-cards.sort-order=desc
Option D is incorrect as VPN Connections will be required to access the Redis Cluster from on-prem servers.
Option E is incorrect. For Redis AUTH, clusters must be enabled with in-transit encryption during initial deployment, not At-Rest encryption.
For more information on Authentication with Redis & Accessing Redis Clusters from a different VPC, refer to the following URLs-
https://docs.aws.amazon.com/AmazonElastiCache/latest/red-ug/auth.html
https://docs.aws.amazon.com/AmazonElastiCache/latest/red-ug/elasticache-vpc-accessing.html