You have an Auto Sealing group of Instances that processes messages from an Amazon Simple Queue Service (SQS)
queue. The group scales on the size of the queue. Processing Involves calling a third-party web service. The web service
is complaining about the number of failed and repeated calls it is receiving from you. You have noticed that when the
group scales in, instances are being terminated while they are processing. What cost-effective solution can you use to
reduce the number of incomplete process attempts?
A.
Create a new Auto Scaling group with minimum and maximum of 2 and instances running web proxy software.
Configure the VPC route table to route HTTP traffic to these web proxies.
B.
Modify the application running on the instances to enable termination protection while it processes a task and disable it when the
processing is complete.
C.
Increase the minimum and maximum size for the Auto Scaling group, and change the scaling policies so they scale less dynamically.
D.
Modify the application running on the instances to put itself into an Auto Scaling Standby state while it processes a task and return
itself to InService when the processing is complete.
D
D
I think B is the right answer.
https://aws.amazon.com/about-aws/whats-new/2015/12/protect-instances-from-termination-by-auto-scaling/
I think B too
AWS calls it “Instance Protection” and not “Termination Protection”
http://docs.aws.amazon.com/autoscaling/latest/userguide/as-instance-termination.html
So I guess it’s D, despite I initially thought it is B as well.
Yep, “Termination Protection” is not valid, this should be “Instance Protection”; Termination Protection exists but it is to prevent “Manual termination through the Amazon EC2 console” not termination when an AS is scaling in
Answer is B.
B.
D is not the right answer.
I also choose B,
ELB will deregister instance if it’s in Standby state.
http://docs.aws.amazon.com/autoscaling/latest/userguide/as-enter-exit-standby.html
C.
Instance in standby, stops receiving new traffic and it can’t be terminated by the auto scaling group as long as it is in standby mode (as its not the part of auto scaling group).
So C is the right answer.
D.
http://docs.aws.amazon.com/autoscaling/latest/userguide/as-enter-exit-standby.html#standby-state
A&C are wrong, they are not cost-effective.
B is wrong termination protection does not prevent AS from terminating the instance,
but Instance protection does.
D
The DisableApiTermination attribute does not prevent Auto Scaling from terminating an instance. To prevent instances that are part of an Auto Scaling group from terminating on scale in, use instance protection.
http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/terminating-instances.html
B is wrong. D is the answer
D is correct answer.
http://docs.aws.amazon.com/zh_cn/AWSEC2/latest/UserGuide/terminating-instances.html
在“限制”中写明了 要防止scale in 时终止实例 应该启用 ASG的实例保护 即 instance protection
而termination protection 是防止因误操作 手动终止实例时使用的一种保护措施
因此B不正确 只能选D了