Pass the Alibaba Cloud Computing ACP-Cloud1 Questions and answers with ValidTests

 You can change the private IP address of an ECS instance after it is created, but you need to stop the instance first. The private IP address must be within the CIDR block of the VPC and the VSwitch that the instance belongs to. You can modify the private IP address of an instance by using the console or the API. References: 3, ACP Cloud Computing Certification - Alibaba Cloud Academy

After stopping an Alibaba Cloud Elastic Compute Service (ECS) instance, you will still be charged for some resources related to that ECS instance, such as disks, snapshots, and public IP addresses, until you release them. The charging policy depends on the billing method and network type of the ECS instance. For pay-as-you-go instances, you can choose whether to enable the No fees for stopped instances feature, which allows you to stop paying for vCPUs and memory when the instance is stopped. However, this feature is only available for VPC-connected instances in some regions1. For subscription instances, you will be charged for the entire subscription period regardless of whether the instance is running or stopped2. References:

1: Billing FAQ - Elastic Compute Service - Alibaba Cloud Documentation Center1

2: Billing overview - Elastic Compute Service - Alibaba Cloud Documentation Center2

Alibaba Cloud VPC uses tunneling technology with unique tunnel IDs to create isolated virtual networks that offer similar isolation capabilities as VLANs in traditional networks. This allows each VPC to function as an independent, secure network environment within the cloud, ensuring traffic separation and resource isolation.

For a service focused on storing and providing fast access to a massive amount of images, the team should use:

Object Storage Service (OSS): For scalable and cost-effective storage of large image datasets.

Elastic Compute Service (ECS): For running the application’s backend and API logic.

Content Delivery Network (CDN): To cache and accelerate image delivery globally, improving access speed for users worldwide.While Auto Scaling is useful for applications with highly variable compute demands, it is not essential for this setup based on the described requirements.

To meet the company’s security requirements, the following solutions should be used together:

A. Enable the VPN on the bastion host (or directly use the VPN image on Alibaba Cloud Marketplace). The administrator uses VPN encrypted communication during O&M. This solution can support secure remote O&M, because VPN (Virtual Private Network) is a technology that creates a secure and encrypted connection over the Internet between the bastion host and the administrator’s device. VPN can protect the data transmitted between the bastion host and the administrator from being intercepted or tampered by malicious third parties1. Alibaba Cloud provides VPN Gateway service that allows users to create VPN connections between VPCs and on-premises data centers, or between VPCs in different regions2. Users can also use VPN images from Alibaba Cloud Marketplace, such as OpenVPN, to create VPN servers on ECS instances3.

B. Build an independent ECS instance as the bastion host or remote logon and O&M, and authorize the bastion host to access ECS instances running other subsystems. This solution can also support secure remote O&M, because a bastion host is a special-purpose ECS instance that acts as a proxy or a gateway for accessing other ECS instances in the VPC. A bastion host can enhance the security of the ECS instances by limiting the exposure of the ECS instances to the public network, and by implementing security policies and monitoring tools on the bastion host4. Alibaba Cloud provides Bastionhost service that allows users to centrally manage the access to cloud servers from external networks and provide secure connections to VPC resources5.

C. Use the security group function of the ECS instance, and respectively deploy ECS instances running different subsystems to independent security groups. This solution can isolate the networks between subsystems, because a security group is a virtual firewall that controls the inbound and outbound traffic of the ECS instances in the group. Users can configure security group rules to allow or deny access based on the network protocol, port, and source IP address. By deploying ECS instances running different subsystems to independent security groups, users can prevent unauthorized access or communication between the subsystems6.

The other solution is not suitable for the company’s scenario, for the following reason:

D. Create multiple ECS instances in the VPC to install subsystems of different departments- Allocate only Intranet IP addresses to all ECS instances, and deploy them in the same security groups. This solution cannot isolate the networks between subsystems, because ECS instances in the same security group can communicate with each other by default, regardless of whether they have intranet or internet IP addresses. Moreover, this solution may also prevent the ECS instances from accessing the internet or providing external services, which may affect the business operation of the company6.

References: What is a VPN? - Virtual Private Network - Cisco, VPN Gateway - Alibaba Cloud, OpenVPN - Alibaba Cloud Marketplace, Bastion Host - Alibaba Cloud Document Center, Bastionhost - Alibaba Cloud, Security groups - Elastic Compute Service - Alibaba Cloud

Modifying the MAC address of an ECS instance’s NIC can cause network disconnection issues because Alibaba Cloud's VPC network infrastructure relies on consistent NIC configuration. Changing the MAC address may prevent the instance from being identified correctly on the network.

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https://cloudacademy.com/course/alibaba-security-monitoring-1275/introduction-to-cloud-monitor/#:~:text=Cloud%20Monitor%20is%20a%20service,safeguard%20your%20products%20and%20business .

Option A is correct because site monitoring is one of the functions provided by CloudMonitor. Site monitoring monitors the availability, connectivity, and domain name resolution of sites. It monitors the connectivity and response time of domain names, IP addresses, and ports, and sends alert notifications based on monitoring results1

Option B is correct because customized monitoring is one of the functions provided by CloudMonitor. Customized monitoring allows you to monitor the metrics of your own applications or services. You can use the CloudMonitor API or SDK to report custom metrics to CloudMonitor and view them on the CloudMonitor console. You can also configure alert rules for your custom metrics2

Option E is correct because cloud service monitoring is one of the functions provided by CloudMonitor. Cloud service monitoring monitors the metrics of Alibaba Cloud services, such as Elastic Compute Service (ECS), Object Storage Service (OSS), ApsaraDB for RDS, and Server Load Balancer (SLB). CloudMonitor collects the metrics of these services and displays them on the CloudMonitor console. You can also configure alert rules for these metrics2

Option C is incorrect because custom firewall is not a function provided by CloudMonitor. Custom firewall is a feature of Alibaba Cloud Security Center, which is a different service from CloudMonitor. Security Center provides security protection for your cloud resources and applications. Custom firewall allows you to customize firewall rules for your ECS instances and control the inbound and outbound traffic3

Option D is incorrect because operation auditing is not a function provided by CloudMonitor. Operation auditing is a feature of Alibaba Cloud ActionTrail, which is a different service from CloudMonitor. ActionTrail records the operations performed on your Alibaba Cloud resources and delivers the audit logs to OSS or Log Service for storage and analysis. Operation auditing helps you track the changes of your resources and comply with security standards4

References:

2: What is CloudMonitor? - CloudMonitor - Alibaba Cloud Documentation Center

1: Introduction to Cloud Monitor - Alibaba Security & Monitoring Course

3: [Security Center - Alibaba Cloud]

4: [ActionTrail - Alibaba Cloud]

SLB (Server Load Balancer) is a service that distributes network traffic across groups of backend servers to improve the service capability and application availability1. SLB supports HTTPS listeners, which allow you to encrypt the data transmission between clients and SLB instances2. HTTPS is a secure version of HTTP that uses SSL/TLS protocols to provide data encryption, integrity, and authentication3.

To use HTTPS listeners, you need to upload SSL certificates to SLB. SSL certificates are digital certificates that use public key cryptography to verify the identity of a website and encrypt the data exchanged between the website and the visitors4. There are two types of SSL certificates: server certificates and client certificates. Server certificates are issued by trusted certificate authorities (CAs) to verify the identity of the website owner and the domain name. Client certificates are issued by the website owner to verify the identity of the visitors5.

SLB supports both one-way and two-way authentication for HTTPS listeners. One-way authentication means that only the server identity is verified by the client. Two-way authentication means that both the server and the client identities are verified by each other. To use one-way authentication, you only need to upload the server SSL certificate to SLB. To use two-way authentication, you need to upload both the server SSL certificate and the client CA certificate to SLB. The client CA certificate is the root certificate or intermediate certificate of the CA that issues the client certificates.

Therefore, if you want to use SLB and ECS instances to deploy two-way authenticated HTTPS websites, you need to host server SSL certificates and client CA certificates on SLB. SLB can host both SSL certificates and CA certificates, and it supports HTTPS two-way authentication. The other statements are incorrect. References: Server Load Balancer(SLB) - Alibaba Cloud, Add an HTTPS listener - Server Load Balancer - Alibaba Cloud Documentation Center, What is HTTPS? - SSL.com, What is an SSL Certificate? - SSL.com, What is a Client Certificate? - SSL.com, [Configure two-way authentication for an HTTPS listener - Server Load Balancer - Alibaba Cloud Documentation Center]

Alibaba Cloud ApsaraDB for RDS offers read/write splitting capabilities, allowing you to distribute read requests to read-only instances and write requests to the primary instance. This setup improves database performance under high traffic by optimizing read workloads, which is particularly useful for MySQL databases deployed in high-demand environments.

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A route table is a set of rules that determine how network traffic is routed within a VPC or between different network instances1. A VRouter is a hub that connects all VSwitches in the same VPC and enables communication between them2. When you create a VPC, a VRouter and a default route table are automatically created for the VPC1. The default route table contains system routes that are automatically generated by the system based on the network topology1. The system routes cannot be modified or deleted1.

However, you can also create custom route tables for your VPC and add custom routes to them1. Custom routes are manually configured by users to route traffic to specific destinations, such as other VPCs, VBRs, VPN Gateways, or NAT Gateways1. Custom routes can be modified or deleted as needed1. You can also associate VSwitches with different route tables to implement fine-grained routing control1.

Therefore, the statement that the routing entries of the route table can not be modified manually is not correct, as it only applies to system routes, not custom routes. The other statements are correct, as each VRouter may have multiple route tables, one default and several custom1; when a VPC is deleted, the corresponding route table is also deleted3; and the default route table cannot be deleted1. References: Route table overview - Virtual Private Cloud - Alibaba Cloud Documentation Center, VRouter overview - Virtual Private Cloud - Alibaba Cloud Documentation Center, Delete a VPC - Virtual Private Cloud - Alibaba Cloud Documentation Center

By default, ECS instances in different zones within the same region are not interconnected via the Intranet. To enable communication between instances across zones, you would need to configure a VPC or use other network configurations. This setup provides isolation and flexibility in managing network traffic within different zones.