To serve Web traffic for a popular product your chief financial officer and IT director have purchased 10 ml
large heavy utilization Reserved Instances (RIs) evenly spread across two availability zones: Route 53 is used to
deliver the traffic to an Elastic Load Balancer (ELB). After several months, the product grows even more
popular and you need additional capacity As a result, your company purchases two C3.2xlarge medium
utilization Ris You register the two c3 2xlarge instances with your ELB and quickly find that the ml large
instances are at 100% of capacity and the c3 2xlarge instances have significant capacity that’s unused Which
option is the most cost effective and uses EC2 capacity most effectively?
A.
Use a separate ELB for each instance type and distribute load to ELBs with Route 53 weighted round robin
B.
Configure Autoscaning group and Launch Configuration with ELB to add up to 10 more on-demand mi large
instances when triggered by Cloudwatch shut off c3 2xiarge instances
C.
Route traffic to EC2 ml large and c3 2xlarge instances directly using Route 53 latency based routing and
health checks shut off ELB
D.
Configure ELB with two c3 2xiarge Instances and use on-demand Autoscailng group for up to two additional
c3.2xlarge instances Shut on mi .large instances.
A
why a ??
answer : a
because the weighted routing policy is used when you have multiple resources that perform the same function (for example, web servers that serve the same website) and you want Amazon Route 53 to route traffic to those resources in proportions that you specify (for example, one quarter to one server and three quarters to the other).
refer : http://docs.aws.amazon.com/Route53/latest/DeveloperGuide/routing-policy.html
By the way, obviously, D is not correct.
Shut on mi .large instances. ~ as mi. instances has been purchased as Reserved Instances. So I prefer A.
Not sure, any new thoughts ?
A.
Use a separate ELB for each instance type and distribute load to ELBs with Route 53 weighted round robin
A for me
D is definitely not correct. We already have c3 2xlarge instances that are not used. Configuring it to a Autoscale group for up to two additional c3.2xlarge instances, does not make much sense.
A seems to be more appropriate for this case
B again adds more instances. We already have 2 unused instances, adding more is not the solution
C We are not sure where the traffic is from. Latency based routing may cause more problems or may not. Its a iffy choice
I think A is the best fit – with weights in Route53 you can balance the load proportional to instance sizes.
A
Worth considering Answer C:
It’s more cost effective since its using 2 ELBs less.
The question is whether latency based routing will be able to distribute the traffic in an optimal manner
Answer is A. There are 2 type of instance used in the scenario. M1 and C3. with same shared load, M1 is 100% capacity but C3 still have a lot capacity unused. So Option A, Separate ELB for different instance type. and use Route53 weight route configure to assign more load to C3 type ELB.
A
Weighted Routing Policy
Use the weighted routing policy when you have multiple resources that perform the same function (for example, web servers that serve the same website) and you want Amazon Route 53 to route traffic to those resources in proportions that you specify (for example, one quarter to one server and three quarters to the other). For more information about weighted resource record sets, see Weighted Routing.