An Alibaba Cloud RDS read-only instance has its data synchronized from the master instance.
Which of the following can be performed by the read-only instance from the RDS management console? (Single answer)
- A . Backup policy configuration and manual backup
- B . B. Database creation or deletion
- C . Editing its own whitelist
- D . Account authorization and account password changing
Which of the following statements is true for Alibaba Cloud RDS? (Single answer)
- A . Multiple databases can be created for one instance.
- B . Databases with the same name are allowed to be hosted on the same instance.
- C . Physical host CPU and Memory resource are not shared among the common type of RDS instances.
- D . All editions of RDS support HA mode.
lf you need to accelerate a certain domain name (such as abc.com) via Alibaba Cloud Content Delivery Network (CDN), you must add it to "CDN Domain Name List" in the CDN service. After added successfully, you will get a CNAME address A. Next, you need to modify domain name resolution and direct the domain name (such as abc.com) to CNAME address A.
Which of the following is a NOT correct description of modifying domain name resolution? (Single answer)
- A . The DNS service provider used by the domain name (such as abc.com) must support intelligent resolution.
- B . The DNS service provider used by the domain name (such as abc.com) can be companies other than Alibaba Cloud.
- C . If your domain name (such as abc.com) is transferred to Alibaba Cloud in advance, and managed by the same Alibaba Cloud account, you can perform one-step resolution modification.
- D . The CNAME address allocated to the domain name (such as abc.com) will point to an IP address. This IP address resolving mechanism is intelligently managed by Alibaba Cloud CDN system.
Company G developed a shopping App. The system is constructed based on Alibaba Cloud products. They use Elastic Compute Service (ECS) instances and object Storage Service (OSS) in North China 1region, and store static web pages and images on OSS.
After the App went online, the access speed in mainland China is acceptable. Recently, the company decided to expand to the U.S. market and requires an acceptable access speed too for U.S. users. To address this requirement, company G should select Alibaba Cloud ___service. (Single answer)
- A . Enabling object Storage Service (OSS) in West US region with Content Delivery Network (CDN) in North China 2 regions
- B . Enabling Object Storage Service (OSS) in North China 1 region with Content Delivery Network(CDN)accelerating West Us(Silicon Valley) region
- C . Enabling Auto Scaling and more Elastic Compute Service(ECS) instances
- D . Enabling Auto Scaling and Content Delivery Network(CDN)
A customer uses Alibaba Cloud Auto Scaling service and creates a scaling group. He/she sets the "Minimum number of instances" to 6 and "Maximum number of instances" to 8.After correctly configuring scaling settings, the customer adds a scaling rule "Adjust to 10 ECS instances " and creates a scheduled task based on this rule. And then, the customer checks the scaling group and see it already contains 6 valid ECS instances, he/she then enables this scaling group immediately.
How many ECS instance will be in the scaling group when the scheduled task is activated once? (Single answer)
- A . 8
- B . 10
- C . 6
- D . 5
Which of the following ports does RDs for MySQL listen on by default? (Single answer)
- A . Port 8080
- B . Port 3060
- C . Port 3600
- D . Port 3306
Which of the following statements is NOT correct, when comparing RDS with a self-built database? (Single answer)
- A . RDS features a high availability of 99.95% while self-built databases require you to implement data protection, primary-standby replication, and RAID all by yourself.
- B . RDS provides automatic backup while self-built databases require you to prepare storage space for backup copies and regularly verify that these copies can be restored.
- C . Self-built database support quick deployment and elastic scaling.
- D . RDS requires no O&M while self-built database require a dedicated DBA for maintenance
which results in high HR costs.
Which of the following statements about file uploading to OSS is NOT correct? (Single answer)
- A . All file uploading method provided by Alibaba Cloud OSS service will support resuming from break point.
- B . If you are uploading some small files(<1m), you can choose PUT method to finish uploading in one HTTP request.
- C . if you are using OSs to store some log files which are continuously being updated it’s better to choose APPEND method instead of overwriting or generating new versions.
- D . If you need to upload very large files it’s better to use multi-part uploading to get the capability of resuming from break point.
in Alibaba Cloud 0bject Storage, users want to use graphical tools to upload and download object files.
Which tools can they use? (Single answer)
- A . ossbrowser
- B . ossutil
- C . osscmd
- D . ossfs
Alibaba Cloud Object Storage Service (OSS) is a massive, highly available, secured and cost-effective storage service. One of the special characteristics of OSS is its superior data reliability, because of its underlying backup technology and policies.
Which of the following statements about OSS backup is correct? (Single answer)
- A . OSS supports 3 internal data copies, so the data can be manually recovered should there be any problem.
- B . Customer has to safeguard their own data. OSS provides various backup interfaces to facilitate offsite backups.
- C . OSS leverages RAID0+1 configuration of its underlying physical hard disks. There is no impact even if 2 hard disks were to fail simultaneously.
- D . OSS supports 3 internal data copies, no human intervention is required to recover the data when anything goes wrong.
Alibaba Cloud Object Storage OSS can upload object files through the console.
What is the largest object file uploaded? (Single answer)
- A . 1GB
- B . 5GB
- C . 10GB
- D . 1TB
Auto Scaling is a management service that can automatically adjust elastic computing resources based on your business needs and policies. This service can automatically adjust. (Single answer)
- A . Number of ECS instances
- B . CPU for ECS instances
- C . Memory size for ECS instances
- D . Bandwidth for ECS instances
When using Auto Scaling, you want to add/remove ECS instances based on the utilization rate of computing resources. For example, you want to remove one ECS instance when the average CPU utilization rate is not greater than 30%. In this case, you need to set the scaling rule "Remove 1 ECS instance" and _____to finish the configuration. (Single answer)
- A . Create a scaling configuration
- B . Configure the attributes of the scaling group
- C . Create a Scheduled task
- D . Create an Event-triggered task
You have bought an ECS instance on Alibaba Cloud. After deploying a Python environment on it which of the following is the easiest and quickest way to monitor whether the Python process is running normally and report an alert if the process is accidentally terminated? (Single answer)
- A . Write a script for monitoring by yourself.
- B . Use process monitor of ECS instance monitoring.
- C . Use site monitoring.
- D . Log on to the ECS instance console.
Many websites have suffered DDoS attacks of different volumes. Therefore, accurate understanding of DDoS attacks is critical to website security protection.
Which of the following statements about DDoS attacks is the MOST accurate? (Single answer)
- A . DDoS attacks primarily target databases.
- B . DDoS attacks crack the server’s logon password by means of a massive number of attempts.
- C . The main purpose of a DDoS attack is to prevent the target server from providing normal services. Currently the DoS attack is one of the strongest and most indefensible website attacks.
- D . The purpose of a DDoS attack is to steal confidential information.
An insurance company has more than 200,000 online orders per day on their platform. in the past one year, the platform has suffered frequent large volume DDoS attacks (exceeding 10 Gbps).
Which of the following Alibaba Cloud products can the customer use to defend against this type of attacks and ensure service availability? (Single answer)
- A . Anti-DDoS Origin Basic Edition
- B . Managed Security Service
- C . Security Center
- D . Anti-DDoS Pro or Premium Service
Alibaba Cloud ECS is a simple and efficient computing service. ECS helps you quickly deploy applications, improve your 0&M efficiency, and reduce IT cost. ECS belongs to this type of service_______.(Single answer)
- A . SaaS (Software as a Service)
- B . PaaS (Platform as a Service)
- C . IaaS (Infrastructure as a Service)
- D . DaaS (Data as a Service)
User A is the system administrator of a company, who often takes business trips to Shanghai. Each time he remotely logs on to the server in Shanghai, an alert is reported, prompting "Someone is remotely logging on to the server. Please pay attention to your server security ".
Which of the following methods can be used to quickly and automatically resolve this problem? (Single answer)
- A . Open a ticket immediately to consult Alibaba Cloud engineers.
- B . Ask the company leaders for help.
- C . Log on to Alibaba Cloud console, and add a frequent logon location to the Security Center configuration item.
- D . Call a friend for help, who is a famous hacker in the industry.
If you need to make the ECS instances under three VSwitches (inside the same Alibaba Cloud VPC) cannot access to each other, meanwhile, not affecting other Intranet connections in this VPC, what should you do? (Single answer)
- A . Create three Security Groups, which respectively include all ECS instances under these three VSwitches. First, configure each of these Security Groups to allow access of all CIDR Blocks. Second, configure each of these Security Groups to forbidden the access of CIDR blocks of the other two VSwitches (given this rule with a higher priority than the previous rule).
- B . Create three Security Groups, which respectively include all ECS instances under these three VSwitches. First, configure each of these Security Groups to allow access of all CIDR Blocks. Second, configure each of these Security Croups to forbidden the access of CIDR blocks of the other two VSwitches (given this rule with a lower priority than the previous rule).
- C . Create one Security Group, which include all ECS instances under these three VSwitches. First, configure each of these Security Groups to allow access of all CIDR Blocks. Second, configure each of these Security Groups to forbidden the access of CIDR blocks of the other two VSwitches (given this rule with a higher priority than the previous rule).
- D . None of these answers are correct.
An online education website is built based on ECS, SLB and Auto Scaling, which greatly reduces resource cost, O&M cost and without compromising system stability and user experience.
Now, the website admin wants to keep the user information (such as source IP, accessed URLs, and duration on each page) for analysis to support their upcoming campaign events.
In this case, which of the following statements is NOT correct? (Single answer)
- A . Let each ECS instance in the scaling group keeps the user access information it processes. Thus, the data saved by these ECS instances can be accessed and analyzed at any time, making the solution not only simple, but also efficient, reliable, and cost-effective.
- B . Save user-related access information to ApsaraDB for RDS in real time or quasi real time, which can then be used for performing query and analysis,
- C . Synchronize user-related access information to ApsaraDB for Memcache in real time or quasi real time. Then, access Memcache using an application or make the data in Memcache persistent based on certain rules, and then can use the persistent data for further analysis.
- D . Synchronize user-related access information to OSS in real time or quasi real time for further use.
For Alibaba Cloud ECS instances in a VPC, you can configure Resource Access Management settings on ECS instances through Security Group.
Which of the following statements is correct? (Single answer)
- A . A security group can contain ECS instances of different VPCs in the same zone.
- B . A security group can contain ECS instances of different VPCs in the same region.
- C . A security group can only contain ECS instances of the same VPC in the same zone.
- D . A security group can contain ECS instances of the same VPC in the same region.
in Alibaba Cloud VPC, the device used for connecting each VSwitch is. (Single answer)
- A . route table
- B . VRouter
- C . ECS
- D . SLB
If an administrator often needs to manage multiple ECS instances in an Alibaba Cloud VPC through the Internet.
Which of the following solutions can meet this need at low costs and without affecting system security. (Single answer)
- A . Modify the VPC Security Group policy, to allow access from the Internet.
- B . None of these answers are correct.
- C . Bind an EIP to each of the ECS instances, and log on to each of these ECS instances to manage them.
- D . Choose an ECS instance from VPC and make it as the bastion host. And then, apply an EIP and bind it to this ECS instance. After that, the administrator can manage other ECs instances through this bastion host.
Which of the following statements about OSS bucket is NOT correct? (Single answer)
- A . Every user can create more than one bucket
- B . Bucket name can be changed after creation
- C . Every bucket should have a unique name
- D . There is no limitation on the number of objects inside a bucket
Which of the following is not the potential cause of latency on an RDS read-only instance? (Single answer)
- A . The load on this read-only instance is significant.
- B . There exists significant load on the ECS that is connected to this read-only instance
- C . The specification of this read-only instance is too low.
- D . This read-only instance’s master instance is performing a lot of write operations.
A company uses Alibaba Cloud SLB with a layer 7 Listener and Auto Scaling at the same time, hoping this combination can help reduce O&M costs and provide a stable and reliable system.
However, because they do not have experience with Alibaba Cloud, the company’s engineers listed some precautions they think they should take, and have given you the list to ask for your advice.
As an Alibaba Cloud expert, you tell them that only ______is a valid concern. (Single answer)
- A . SLB instances must have Health Check enabled, or they cannot be used together with Auto Scaling
- B . All ECS instances under the same SLB instance must be running the same operating system
- C . All backend servers under the same SLB instance must be in the same Scaling Group
- D . All backend servers under the same SLB instance must have the same configuration
When using Alibaba Cloud SLB, users can enable the health check function. Layer-4 SLBs (TCP protocol) determine the availability of ECS instances through_____________. (Single answer)
- A . Whether the 3-way handshake can be established between the backend ECS instance and the SLB
- B . Special characters contained in the message returned from backend ECS instances
- C . Status codes returned from backend ECS instances
- D . Length of message returned from backend ECS instances
Using Alibaba Cloud ECS, SLB, and Auto Scaling in combination, you can build a stable, highly efficient, and secure system at low cost. This system can transfer loads based on predefined policies, and automatically scales resources based on changes in business volume.
Which of the following statement is correct? (Single answer)
- A . An SLB instance can bind multiple Auto Scaling groups, and the scaling configurations of these scaling groups can be different
- B . An SLB instance can bind multiple Auto Scaling groups, but the scaling configurations of these scaling groups must be consistent
- C . A scaling group may correspond to multiple SLB instances, but they must be within the same region
- D . A scaling group may correspond to multiple SLB instances, but they must be within the same zone
SLB is a load balancing service that distributes traffic to multiple cloud servers. It provides a wide range of functions to meet the needs of various business scenarios. If a user wants to use SLB and ECS instances to deploy two-way authenticated HTTPS websites, the following statement is correct_________.(Single answer)
- A . You need to host server SSL certificates and client CA certificates on SLB
- B . SLB can only host SSL certificates, not CA certificates
- C . SLB can only host CA certificates, not SSL certificates
- D . SLB can only support HTTPS one-way authentication
Alibaba Cloud SLB includes these components: external service requests, Listener, Load Balancer, Backend Server, etc.
Which of the following statements is correct about Listeners? (Single answer)
- A . Listener includes SLB policies and forwarding rules.
- B . Listener is a collection of ECS instances that provide external services.
- C . Listener refers to an SLB instance.
- D . By configuring monitoring rules, Listener can generate monitoring indexes for SLB.
You deployed the website on an Alibaba Cloud Elastic Compute Service (ECS) instance. After sometime, you worried that the ECS instance might be cracked by brute-force password cracking.
To address this issue, you can use Alibaba Cloud’s ___ product.
- A . Object Storage Service (oss)
- B . Cloud Monitor
- C . Server Load Balancer (SLB)
- D . Security Center
As a technical employee at a startup company, you deploy static files such as images, and videos on the same ECS instance to provide services.
After some time, due to business growth, you find that those static files are using too much ECS diskspace.
To quickly address this issue, you should choose Alibaba Cloud_______.
- A . Server Load Balancer (SLB)
- B . Apsara DB for RDS
- C . Object Storage Service (oss)
- D . Auto Scaling
Cloud Disk is a kind of block storage product provided by Alibaba Cloud (especially for ECS). It features low latency and high reliability.
Which of the following statements is true for Cloud Disk?
- A . A Cloud Disk can be attached to an instance in a different region than the Cloud Disk.
- B . Cloud Disk can be attached between ECS instances under the same account and in the same zone.
- C . Cloud Disk cannot be attached or detached between ECS instances.
- D . cloud Disk can be used directly without formatting.
You deployed a MySQL database on an Alibaba Cloud Elastic Compute Service (ECS) instance. Due to traffic increases, you want to improve the performance by splitting read/write requests.
Therefore, you can use Alibaba Cloud_______to solve this issue.
- A . Object Storage Service (oss)
- B . SSD cloud disk
- C . Apsara DB for RDS
- D . Table Store
Alibaba Cloud ECS provides multiple instance types to meet the needs of different business scenarios. A medium-sized enterprise user wants to use two ECS instances, one to deploy a single Tomcat service
and the other one to deploy Memcache.
Which of the following configurations is most recommended?
- A . Tomcat: 4 cores, 4G,
Memcache: 2 cores, 8G - B . Tomcat: 4 cores,4G,
Memcache: 2 cores,16G - C . Tomcat: 4 cores, 8G,
Memcache: 2 cores, 8G - D . Tomcat: 4 coros,8G,
Memcache: 2 cores,16G
When using ECS, you don’t have to stop the ECS instance before resizing the system disk.
- A . TRUE
- B . FALSE
When creating an Alibaba Cloud VPC, you must specify Intranet network segments used in the VPC with CIDR Block. This CIDR Block can later be modified after the VPC is created
- A . TRUE
- B . FALSE
Alibaba Cloud object storage (Object Storage Service, OSS for short) provides massive, secured, relatively low-cost, and highly reliable cloud storage service. Users can upload and download files to/from OSS via WEB console or API.
- A . TRUE
- B . FALSE
A route table refers to the list of routing entries on a VRouter in Alibaba Cloud VPC. You can create/delete any route tables in VPC.
- A . TRUE
- B . FALSE
When using Alibaba Cloud SLB to forward layer 7 (HTTP) service requests, SLB will replace the IP address in the HTTP header file to forward requests.
Therefore, the source IP address that can be seen on the backend ECS instance is the IP address of SLB instead of the client’s real IP address.
- A . TRUE
- B . FALSE
After stopping an Alibaba Cloud Elastic Compute Service (ECS) instance, since the ECS instance is stopped, you will not be charged for anything related to that ECS instance until you start the instance again regardless of which region the instance is located in.
- A . TRUE
- B . FALSE
When using Alibaba Cloud SLB, users can enable the health check function. If a backend ECS instance A is running abnormally, SLB will isolate it and forward the requests to other ECS instances, and when the backend ECS instance A is back to normal, SLB will again forward requests to it.
- A . TRUE
- B . FALSE
After activating an Alibaba Cloud Elastic Compute Service (ECS) instance, you want to monitor the status of the ECS instance via Alibaba Cloud console. Therefore, you must activate and purchase Alibaba Cloud CloudMonitor service to meet this demand.
- A . TRUE
- B . FALSE
Alibaba Cloud Security Center provides brute force password cracking protection. Therefore, users having activated Security Center neither need to modify the administrator password of their ECS instances periodically nor need to set a complicated password.
- A . TRUE
- B . FALSE
Many of Alibaba Cloud services provide highly reliable data storage capacity. For example, Object Storage Service (OSS) promises that its data reliability is no less than 99.99999999%. This high data reliability is solely achieved by RAID 0+1 redundancy technology.
- A . TRUE
- B . FALSE
Alibaba Cloud SLB can distribute user requests to backend ECS instances. These ECS instances must have the same specification (CPU, Memory).
- A . TRUE
- B . FALSE
Alibaba Cloud Content Delivery Network (CDN) is a distributed network that is built and overlaid on the bearer network. Moreover, it is composed of edge node server clusters distributed across different
regions.
It replaces the traditional data transmission mode, which is centered on Web servers. CDN acceleration is especially suitable for scenarios where there is significant site traffic and the static resource is repeatedly used by different users. The higher the repeated access rate, the more significant the acceleration effect.
- A . TRUE
- B . FALSE
RDS instances are automatically created in master-slave mode without any extra costs or associated configuration.
- A . TRUE
- B . FALSE
0n an Alibaba Cloud Elastic Compute Service (ECS) instance, if you change the MAC address of the NIC within the operating system, this may result in network connection failure.
- A . TRUE
- B . FALSE
All versions of Alibaba Cloud RDS uses master-slave mode to ensure high availability. When the master database fails, RDS will switch to the standby database within 30 seconds.
- A . TRUE
- B . FALSE
In Auto Scaling, a scaling group refers to the collection of ECS instances deployed with the same applications, where these ECs instances can be charged by monthly subscription or Pay-As-You-Go. For scenarios with abrupt service traffic change, Pay-As-You-Go ECS instances can meet service requirements with minimizing cost.
For monthly subscription ECS instances, you can manually add the idle instances to the scaling group to take full advantage of idle resources.
- A . TRUE
- B . FALSE
After activating an SLB, it will be assigned an IP address. The SLB will keep this IP address until it is released.
- A . TRUE
- B . FALSE
Alibaba Cloud’s object storage (Object Storage Service, OSS for short) can be used to store a large amount of data, but there is still a maximum number of files in a single bucket.
- A . TRUE
- B . FALSE
Alibaba Cloud Server Load Balancer (SLB) provides services for distributing traffic among multiple ECS instances. SLB can expand the application system’s service capacity through traffic distribution, and improve the system’s availability by eliminating SPoFs (Single Points of Failure).
Which of the following
statements are correct? (Number of correct answers: 2)
- A . When recreating an SLB instance that has an Internet lp address, a new Internet lP address will be assigned to the SLB instance.
- B . Before using SLB to provide external services, make sure that you have installed and correctly configured the SLB agent on all of the backend ECs instances.
- C . One of SLBs features is the Health Check. f some of the backend ECS instances are down, whereas other backend ECS instances can still provide services, then the system can continue to work normally.
- D . SLB provides a function to automatically synchronize data among backend ECS instances using rsync remote synchronization technology
Alibaba Cloud OSS is a cloud storage service that features massive capacity, outstanding security low costs, and high reliability.
When talking about information security, the advantages of using OSS are_____. (Number of correct answers: 2)
- A . Supports Anti-DDoS, automatic traffic cleaning, and "black holing" without any extra charges.
- B . Offers a multi-user isolation mechanism directly, no need to leverage RAM.
- C . offers Server Side Encryption function for data security protection in OSS
- D . provides Primary/Secondary region configuration based data reliability protection.
Which of the following Alibaba Cloud products can provide Anti-DDoS service? (Number of correct answers: 2)
- A . Security Center
- B . Anti-DDoS Origin Service
- C . Anti-DDoS Pro Service
- D . Cloud Firewall
Cloud computing adopts a common model in Distributed System. It distributes a computing task to the resource pool (comprised of a large number of computers). Elastically utilize the resource pool can allow applications to obtain computing capacity, storage space, and message services according to the needs.
Which of the following statements are correct about cloud computing? (Number of correct answers: 4)
- A . Large scale
- B . High availability
- C . Service on demand
- D . Versatility
- E . Container based
- F . Only supports single tenant
Alibaba Cloud CloudMonitor allows you to customize monitoring metrics and alert policies.
Which of the following statements about customized monitoring are correct? (Number of correct answers:2)
- A . Users can monitor concerned services and report collected monitoring data to CloudMonitor, so that cloudMonitor processes the data and generates alerts according to the result.
- B . Users can only select limited and fixed templates, and monitor specified server performance indicators.
- C . The number of customized monitoring metrics is limited, and programs used to report metric data must be deployed on the Alibaba Cloud server.
- D . The number of customized monitoring metrics is not limited, and programs used to report metric data may be deployed on devices other than the Alibaba Cloud server.
When distributing loads to multiple ECS instances with an Alibaba Cloud Server Load Balancer (SLB). you can obtain the real IP addresses of users who initiate the requests through (Number of correct answers: 2)
- A . ForLayer-7 services, SLB obtains the real IP addresses of the visitors by means of HTTP Heard: X-Forwarded-For, but the "Obtain the Visitors Real IP Address" function must be enabled first.
- B . For Layer-4 services, you can obtain the visitor’s Real lP addresses directly, without any additional settings.
- C . ForLayer-4 services, SLB obtains the real IP addresses of the visitors by means of the HTTP Header: X-Forwarded-For, but the "Obtain the Visitor’s Real IP Address" function must be enabled first.
- D . For Layer-7 services, you can obtain the visitors’ real IP addresses directly, without any additional settings.
AVirtual Private Cloud (VPC) is an isolated network environment that is completely isolated from each other. The following statements about VPC are correct______. (Number of correct answers: 2)
- A . Each VPC has an independent tunnel ID, and a tunnel ID corresponds to a virtualized network.
- B . Subnets can be divided like the traditional network environment. Different cloud servers within each subnet are connected by the same router, and different subnets are interconnected by switches.
- C . The internal networks of different VPCs are completely isolated and can be interconnected through IP addresses mapped to the outside.
- D . ECS instances in a VPC use security group firewalls for Layer 2 network access control.
You are using Auto Scaling with one scaling group already created, then you want to execute a task at a specific time such as removing 1 ECS instance every night at 00:00.
To achieve this, which of the following operations should be performed? (Number of correct answers: 2)
- A . Create a new scaling group.
- B . Create a scaling rule.
- C . Create a scheduled task.
- D . Create an event-triggered task.
Availability Zones refer to data centers in the same region with independent power grids and networks.
Which of the following statements are true for Zones? (Number of correct answers:3)
- A . if the disaster recovery requirements of your applications are demanding it is recommended that you deploy ECS instances in the same Region and Zone.
- B . The network latency between inter-Zone ECS instances is lower.
- C . Intranet communication is available between different zones in the same region, and datacenter level fault isolation can be achieved between Zones.
- D . whether you place ECS instances in the same Zone depends on the requirements on disaster recovery and network latency.
- E . if your applications require a low network latency between ECS instances, it is recommended that you create ECS instances in different Zones.
Alibaba Cloud Content Delivery Network (CDN) is a distributed network that is built and overlaid on the bearer network. Moreover, it is composed of edge node server clusters distributed across different regions.
It replaces the traditional data transmission mode, which is centered on Web servers. If a user finds that the CDN cache hit rate is low while using the CDN, the possible reasons are. (Number of correct answers: 3)
- A . When websites have low access traffic and the files are not popular enough, the CDN will receive fewer requests and result in lower cache hit rate.
- B . If the cache configuration is inappropriate (ex. overly short Cache Expiry Time for popular files), this may result in frequent back-to-source operations.
- C . Insufficient bandwidth was selected when enabling the CDN service, making the service capacity reaches the limit.
- D . If the origin site has a largo number of dynamic resources or mostly non-cashback content, this can also lead to frequent back-to-source operations.
- E . Tho HTTP Header setting may cause the cache to fail. In this case, users must check the origin site’s “Cacho-Control” and “Expires” settings.
In Auto Scaling, the cool-down time of a scaling group refers to the lockout period after a scaling activity has been executed successfully.
Which of the following statements about cool down time are true? (Number of correct answers: 2)
- A . During the cool-down time, only the scaling activities in the same scaling group are locked.
- B . You can’t skip a scaling group’s cool-down time period anyway right after a scaling activity is just finished.
- C . When multiple ECS instances are added or removed from a scaling group, the cool-down time begins only when the last instance has been added or removed from the scaling group.
- D . During the cool-down time of a scaling group, only the alarms from CloudMonitor can bypass the cool-down time and trigger scaling activities, whereas others will still subject to the cool-down time, such as the manually triggered scaling activities.
A user builds an ECS + SLB -t RDS business application architecture on the cloud, and uses Auto Scaling to flexibly scale-in and scale out ECS instances. For business reasons, you need to use Apsara DB for Redis as a cache for hot data storage to ensure high-speed data access for applications. However, the Auto Scaling Scaling Group cannot be associated with a Redis instance directly, you need to manually configure ECS instances to be added to or removed from the Redis whitelist, which is time-consuming, laborious and inefficient.
If you are an Alibaba Cloud architect, which 2 Auto Scaling and OOS features would you recommend, in order to automatically add and remove instances from the Redis whitelist?
- A . Auto-Scaling lifecycle hooks
- B . OOS Template
- C . MNS
- D . Instance launch template
To connect VPC with your traditional IDC. Alibaba Cloud currently supports the following methods: ________________ (Number of correct answers: 2)
- A . VPN Gateway
- B . HTTP agent
- C . Connection through a stopping stone
- D . Leased line connection
Which of the following database engines are compatible with RDS? (Number of correct answers: 3)
- A . MySQL
- B . PostgreSQL
- C . SQL Server
- D . PPAS
- E . Sybase
Which of the following scenarios can be done using Alibaba Cloud Express Connection? (Number of correct answers: 2)
- A . Intranet communication between two VPCs under the same account in the same region
- B . Intranet communication between two VPCs in different accounts and different CIDR Blocks
- C . Intranet communication between VPCs and Smart Access Gateway in customers different branch offices
- D . Intranet communication between a VPC and servers in an external IDC
Auto Scaling is a management service that can automatically adjust elastic computing resources based on your business needs and policies It supports adding an existing ECS instance into the scaling group but imposes certain requirements on instance region In this case, which of the following statements is true?
- A . The instance and the scaling group must be in the same region and zone.
- B . The instance and the scaling group must be in the same region but not necessarily the same zone.
- C . Each scaling group can span up to two regions. After adding the ECS instance, the number of regions of all the ECS instances in the scaling group must be no greater than two.
- D . The instance and the scaling group can be in different regions and zones.
B
Explanation:
According to the Alibaba Cloud documentation1, Auto Scaling is a service that automatically adjusts the number of elastic computing resources based on your business demands and policies. When the demand for computing resources increases, Auto Scaling automatically adds ECS instances to ensure sufficient computing capabilities. When the demand decreases, Auto Scaling automatically removes ECS instances to reduce costs.
Auto Scaling supports adding an existing ECS instance into the scaling group, but the instance must meet some requirements 1. One of the requirements is that the instance and the scaling group must be in the same region. However, they do not have to be in the same zone. A zone is a physical area within a region that has independent power grids and networks. A region is a geographic area where Alibaba Cloud deploys its resources. Therefore, the correct answer is B.
Reference: 1: Auto Scaling: Automatically Adjusts Computing Resources – Alibaba Cloud
2: Introduction to Auto Scaling – Alibaba Cloud Document Center