A video streaming company uses SLB to distribute user requests to 30 ECS instances (the 30 ECS instances have the same configuration). Yet, the company finds that the service traffic soars dramatically every night from 20:00 to 02:00. According to their calculation, the evening traffic is 100% higher than the traffic in other periods of time. To properly respond to user requests, which of the following methods is most preferred from the perspective of cost and implementation simplicity?
Auto Scaling can automatically remove unhealthy ECS instances from the scaling group (this feature is called Elastic Self-Health). Yet, after removal, the user has to manually add equivalent amount of new ECS instances back to the scaling group.
RDS for MySQL is a PaaS, which means after creating the RDS instance, the user does not need to take care of the underlying OS, runtime environment of software packages. These would be taken care of by Alibaba Cloud.
In mainland China, the approval requirements for business record filing vary depending on provincial communication management bureaus.
Company A builds a sales management platform based on Alibaba Cloud services, using 3 ECS instances. One of the ECS instance has MySQL installed as the database server of the platform, the other two are used as WEB servers. After some time, due to the rapid increase of employees and sales analysis requests, the performance of the platform is challenged in terms of response time. Through CloudMonitor, it is found that the average CPU usage reaches 70% for the two WEB server ECS instances and the database load reaches 75% for the database server ECS instance. In this situation, company A may choose which Alibaba Cloud services to improve the performance . (Choose two.)