Elastic Compute Service (ECS) functions as an important infrastructure for services. However, the deployment of ECS instances is limited to regions or countries. To address this issue, you can use ECS together with Dynamic Content Delivery Network (DCDN). DCDN and ECS help you deploy cost-effective, high-performance, and highly reliable networks and services. DCDN can accelerate the delivery of static and dynamic content on ECS instances, and provide computing and security services on points of presence (POPs). You can deploy services across the world with a minimum number of ECS instances.

Background information

This section briefly introduces ECS and DCDN.
  • DCDN

    DCDN is a virtual network that consists of POPs. It accelerates content delivery and provides computing capabilities that accelerate the delivery of dynamic content or both static and dynamic content. DCDN supports a wide array of protocols, including HTTP, HTTPS, Transmission Control Protocol (TCP), User Datagram Protocol (UDP), and WebSocket. DCDN has more than 3,200 POPs deployed across the world to provide protection and computing capabilities. For more information, see DCDN.

  • ECS

    ECS is a scalable cloud service. It helps you minimize IT expenses and improve operation and maintenance (O&M) efficiency. This allows you to focus on the innovation of core services. For more information, see Elastic Compute Service.

Scenarios

DCDN is suitable for various industries, including online education, gaming, retail, finance, media, and social media.
Online educationGamingRetailFinanceMediaSocial network
  • APIs
  • Online examination
  • Online programming
  • Interactive whiteboards
  • Learning and examination reports
  • Uploads of images and audio content
  • Curriculum
  • Knowledge communities
  • Online chat
  • Online shops
  • APIs
  • Browser games
  • Turn-based games
  • Real-time interaction
  • Online multiplayer games
  • Deployment of game servers
  • In-game purchases
  • Online chat
  • Player rankings
  • Installation packages and resource plans
  • Online shops
  • APIs
  • Commodity search
  • Orders and transactions
  • Shipping updates
  • Online customer service
  • Promotional HTML5 pages
  • Sales promotions
  • Flash sales
  • Cross-border e-commerce
  • Apps and websites
  • Financial transactions
  • Financial investments
  • Cross-border financial services
  • Financial markets
  • Financial news and information
  • Real-time quotation
  • SSL and VPN services for enterprises
  • Cloud desktop
  • IPv6 services
  • Websites and apps
  • News and information
  • Breaking news
  • Logon, registration, and query services
  • Personalized recommendations
  • Comments, replies, and likes
  • APIs
  • Online chat
  • File synchronization
  • Breaking news
  • Information graphics
  • Uploads of images and text
  • Comments and replies
  • Online shops
  • Likes and gifts
  • Personal information display

Benefits

DCDN provides the following benefits:
  • Acceleration of static and dynamic content

    Traditional CDN services can accelerate only static content delivery. DCDN can accelerate both static and dynamic content.

  • Compatibility with multiple protocols

    DCDN supports a wide array of protocols, including HTTP, HTTPS, WebSocket, TCP, and UDP. This allows you to accelerate content delivery at different layers.

  • Cost-effectiveness

    DCDN minimizes expenses on ECS bandwidth, computing resources, and connections because content can be cached on distributed DCDN nodes.

  • High availability

    DCDN has more than 3,200 POPs deployed across the world. These POPs support a wide array of features including protection and IPv6, which allow you to keep your services available and meet different business requirements.

  • Edge computing

    DCDN allows you to customize features such as A/B testing, URI rewrite, and rate limiting on edge nodes.

Architecture

The following figure shows how DCDN and ECS work with each other:Architecture
Assume that you purchase ECS instances in Region A and Region B. Applications are deployed on the ECS instances and Server Load Balancer (SLB) is used to balance loads. DCDN is used to accelerate the delivery of content on the ECS instances. After a domain name is added to DCDN, static content and dynamic content requested by users are intelligently identified by DCDN. Then, DCDN accelerates the delivery of static content or both static and dynamic content.
  • Accelerate the delivery of static content

    Static content is cached on DCDN nodes. Users can retrieve static content from the nearest nodes.

  • Accelerate the delivery of dynamic content

    If content requested by some requests, such as POST requests, is not cached on DCDN nodes, DCDN nodes redirect the requests to the origin server to retrieve content based on an intelligent scheduling system. The system selects an optimal route for redirection.

  • Accelerate the delivery of both dynamic and static content

    DCDN intelligently identifies static and dynamic content. Static content is cached on DCDN nodes. Users can directly retrieve the cached static content from the nearest DCDN nodes. Requests for dynamic content are redirected to the origin server through an optimal route selected by the intelligent scheduling system.

Configuration procedure

Prerequisites

Before you start, make sure that the following requirements are met:
  • An ECS instance is created and applications are deployed on it. The ECS instance is assigned a public IP address. If you have configured an SLB instance for the ECS instance, make sure that the SLB instance is assigned a public IP address and can provide services to external systems.
  • A domain name with a valid Internet Content Provider (ICP) number is prepared. If the domain name does not have an ICP number, you can apply for one through Alibaba Cloud ICP Filing System.
  • DCDN is activated. For more information, see Activate DCDN.

Procedure

Configuration procedure

Basic settings (required)

Step 1: Add a domain name to DCDN

  1. Log on to the DCDN console.
  2. In the left-side navigation pane, click Domain Names.
  3. On the Domain Names page, click Add Domain Name.
  4. On the Add Domain Name page, configure the parameters that are described in the following table.
    Add Domain Name
    ParameterDescription
    Domain Name to Accelerate
    • Domain name type: Specify a domain name such as example.aliyundoc.com or a wildcard domain name such as *.aliyundoc.com.
    • Domain name format: The domain name must be in lowercase letters. Chinese characters are not supported.
      Important

      If the domain name contains Chinese characters such as 阿里云.网址, you must apply for an ICP number for the domain name in Chinese characters, and use the tool Punycode to convert the domain name to its ASCII equivalent, such as xn--fiq****.xn--eq****. Then, you can specify it as the domain name to be accelerated.

    • Requirements for wildcard domain names: For more information, see Does DCDN support wildcard domain names? .
      Important
      • The wildcard domain name that you specify and the domain names that match the wildcard domain name must belong to the same Alibaba Cloud account. Otherwise, an error message appears when you add domain names. If you need technical support from Alibaba Cloud, submit a ticket
      • If a wildcard domain name is not added to DCDN, you can add the domain names that match the wildcard domain name to DCDN by using different Alibaba Cloud accounts.
    • You cannot add domain names that have been added to other Alibaba Cloud services.

      If the system prompts that the domain name is added to other Alibaba Cloud services such as ApsaraVideo VOD and Alibaba Cloud CDN, submit a ticket

    • Each Alibaba Cloud account can add up to 50 domain names to DCDN.

      If the average daily peak bandwidth values of your domain names exceed 50 Mbit/s, you can submit a ticket to add more domain names to DCDN. Make sure that the increase of domain names does not incur business risks.

    • The content that is delivered from the domain name must abide by the relevant laws and regulations, and comply with the Terms of Service for DCDN. For more information, see Before you start.
    Resource GroupSelect the default resource group or a custom resource group. For more information about how to create a resource group, see Create a resource group.
    Business TypeSelect DCDN.
    Acceleration RegionChinese Mainland Only is selected in this example. If you select Chinese Mainland Only or Global, you must apply for an ICP number for the domain name. We recommend that you perform ICP filing by using Alibaba Cloud ICP Filing System. The Ministry of Industry and Information Technology (MIIT) may not immediately update the data in the database after you submit domain name information. We recommend that you configure the domain name 8 hours after you submit the domain name information.
    Note The pricing varies based on the acceleration region. Select an acceleration region based on your business requirements. For more information about billing, see DCDN pricing.
  5. On the Add Domain Name page, click Add Origin Server and configure the parameters that are described in the following table.
    Add Origin Server
    ParameterDescription
    Type

    Select the type of the origin server and enter the address of the origin server.

    • OSS Domain
      • If you use an Object Storage Service (OSS) bucket as the origin server, you can enter the public domain name of the OSS bucket, such as, ***.oss-cn-hangzhou.aliyundoc.com. Internal domain names of OSS buckets are not supported.
      • You can obtain the public domain name of an OSS bucket in the OSS console. You can also select the domain name of an OSS bucket that belongs to the current Alibaba Cloud account from the Domain Name drop-down list.
    • IP

      You can enter public IP addresses of one or more servers. Public IP addresses of Alibaba Cloud Elastic Compute Service (ECS) instances do not need to be reviewed. Private IP addresses are not supported.

    • Site Domain
      You can enter the domain name of an origin server. To configure multiple domain names, repeat the preceding steps.
      Note
      • The origin domain name must be different from the accelerated domain name. If the origin domain name is the same as the accelerated domain name, a DNS resolution loop occurs, and requests cannot be redirected to the origin server.
      • The domain name must be in lowercase letters.
      • If the domain name contains Chinese characters such as 阿里云.网址, you must apply for an ICP number for the domain name in Chinese characters, and use the tool Punycode to convert the domain name to its ASCII equivalent, such as xn--fiq****.xn--eq****. Then, you can specify it as the domain name to be accelerated.
    Priority

    You can configure priorities to specify primary and secondary origin servers. The primary origin server has a higher priority than the secondary origin server. DCDN preferentially redirects requests to the primary origin server.

    For example, if you specify Origin Server A as the primary origin server and specify Origin Server B as the secondary origin server, requests are preferentially redirected to Origin Server A. When Origin Server A is down, requests are redirected to Origin Server B until Origin Server A works as expected again.

    Weight
    If origin servers have the same priority, DCDN redirects requests to the origin servers based on the weights of the origin servers. This implements load balancing between the origin servers. You can specify a weight based on your business requirements.
    • The weight of an origin server ranges from 0 to 100. An origin server that has a higher weight receives more requests.
    • The default value is 10.

    For example, you specify Origin Server A and Origin Server B as primary origin servers. If the weight of Origin Server A is 80 and the weight of Origin Server B is 20, DCDN redirects 80% of requests to Origin Server A and 20% of requests to Origin Server B.

    Port
    Select a port based on the protocol that is supported by the origin server.
    • Port 80: Requests are redirected to the origin server over port 80.
    • Port 443: Requests are redirected to the origin server over port 443. Make sure that the origin server supports HTTPS.
    Note Before you can specify a custom port, you must set Static Origin Protocol Policy and Dynamic Origin Protocol Policy to HTTP after you add a domain name. For more information, see Configure the static origin protocol policy and Configure back-to-origin requests to retrieve dynamic content.
  6. After you configure an origin server, click Next.
  7. Wait for manual verification.

    After the domain name passes the verification, the status of the domain name changes to Enabled. In this case, the domain name is added to DCDN.

Step 2: Run tests (optional)

After you add a domain name to DCDN, we recommend that you test whether the domain name is accessible before you update the CNAME record of the domain name. This ensures that DNS updates do not affect your business.
Note During the test, requests are sent to DCDN points of presence (POPs). You are charged for the basic services and value-added services of DCDN that you have used. The billing rules of DCDN apply in the test. For more information, see Overview.
  1. Obtain the CNAME of the domain name.
    1. Log on to the DCDN console.
    2. In the left-side navigation pane, click Domain Names.
    3. On the Domain Names page, copy the CNAME of the domain name.
      Note Copy the CNAME of the domain name that is in the Normal state.
      Copy CNAME
  2. Obtain the IP address of the CNAME.
    Note The following IP address is an example returned by running the ping command and is for reference only. To obtain the actual IP address of your CNAME, run the ping command to ping your CNAME.
    • Windows: To obtain the IP address of your CNAME, open the command-line interface and run the ping CNAME command
    • macOS: To obtain the IP address of your CNAME, open the command-line interface and run the dig CNAME command MAc dig CNAME
  3. Add the IP address and domain name to the hosts file of the on-premises machine.

    You must add the IP address obtained from Step 2 and the domain name to the hosts file of the on-premises machine. Make sure that you add the IP address before the domain name.

    In this example, the domain name is example.com, the CNAME is example.com.w.kunlunsl.com, and the IP address of the CNAME is 192.168.0.1.

    • The path of the hosts file in Windows is C:\Windows\System32\drivers\etc\hosts. The following figure is an example. Example
    • The path of the hosts file in macOS is Finder > Go > Go to the folder > /etc/hosts. The following figure is an example. hosts file
  4. Test whether the domain name is accessible.
    After you add the IP address and domain name to the hosts file, you can open the browser and enter the domain name in the address bar to test the connectivity. You can view the test result by using the developer tool of the browser.
    • If the IP address in the Remote Address field is the same as the one that you add to the hosts file, the configuration is valid. You can configure the CNAME on the DNS service provider side. Test the connectivity of the website
    • If the IP address in the Remote Address field is different from the one that you add to the hosts file, the configuration is invalid. Make sure that you add the IP address of the CNAME to the hosts file.

    After you access the domain name, you can also test other features by using the on-premises machine.

Step 3: Add a CNAME record

You must add a CNAME record for the domain name at your DNS service provider. Alibaba Cloud DNS is used in this example to demonstrate how to add a CNAME record. The procedure for adding a CNAME record at a third-party DNS service provider is similar.

  1. Log on to the DCDN console, navigate to the Domain Names page, and then copy the CNAME of the domain name.
    Domain name management
  2. Add a CNAME record.
    1. Log on to the Alibaba Cloud DNS console with the Alibaba Cloud account to which the domain name belongs.
    2. Optional:In the Alibaba Cloud DNS console, add a domain name that is not registered with Alibaba Cloud.
      Note If the domain name is not registered with Alibaba Cloud, you must add the domain name to Alibaba Cloud DNS before you can add a DNS record for it. For more information, see Domain management. If the domain name is registered with Alibaba Cloud, skip this step.
    3. On the Domain Name Resolution page, find the root domain of your domain name and click DNS Settings in the Actions column.
    4. Click Add DNS Record and add a record.
      Note The CNAME record of a specific domain name takes precedence over that of a wildcard domain name. If you want to accelerate a wildcard domain, where the DNS record contains an asterisk (*), you need to delete all other DNS records that match the wildcard domain.
      Add a record
      ParameterDescriptionExample
      Record TypeSelect CNAME from the drop-down list. CNAME
      Hostname
      • For root domains, enter @.
      • For wildcard domains, enter *.
      • For subdomains, enter the prefix of the subdomain.

      For more information about subdomain names, see Add a CNAME record for a domain name.

      • Root domains
        • aliyundoc.com: @
        • aliyundoc.com.cn: @
      • Wildcard domains
        • .aliyundoc.com: *
        • .aliyundoc.com.cn: *
        • *.example.aliyundoc.com: *.example
        • *.example.aliyundoc.com.cn: *.example
      • Subdomains
        • example.aliyundoc.com:example
        • example.aliyundoc.com.cn: example
        • www.example.aliyundoc.com: www.example
        • www.example.aliyundoc.com.cn: www.example
      Note .com.cn is a top-level domain that consists of two hierarchical levels.
      DNS Request SourceSelect Default from the drop-down list.We recommend that you keep the default setting.
      Record Value
      Enter the CNAME of the domain name.
      Note Each accelerated domain name is assigned a unique CNAME. Subdomains cannot use the CNAME of the root domain. If you want to accelerate a subdomain, add the subdomain to DCDN. Alibaba Cloud then assigns a CNAME to the subdomain. Alternatively, you can add a wildcard domain name to DCDN. Subdomains that match the wildcard domain name are mapped to the CNAME of the wildcard domain name. For more information, see Add a domain name.
      		www.example.com.w.kunlunsl.com
      TTL PeriodEnter a time-to-live (TTL) value for the CNAME record. A smaller value indicates that the record is updated quicker. The default TTL value is 10 minutes. We recommend that you keep the default setting.
    5. Click OK.
      If you add a CNAME record, it takes effect immediately. If you modify the CNAME record, it takes 10 minutes for the updates to take effect because the default TTL value of a CNAME record is 10 minutes. The time period varies based on the TTL value that you specify for the CNAME record. The system may prompt that you must add a CNAME record. Ignore the message.
Step 4: Verify that the CNAME record works as expected
  • Method 1: Quick verification in the DCDN console
    1. Log on to the DCDN console and navigate to the Domain Names page.
    2. Select the domain name and move the pointer over the CNAME Status column. The CNAME Configuration Guide tooltip appears.
    3. Click Open Configuration Guide and then click Search.
  • Method 2: Run the ping command to ping the domain name
    1. Open Command Prompt in Windows.
    2. Run the ping command to ping the domain name. If the CNAME in the output matches the CNAME that is assigned to the domain name in the DCDN console, the DCDN service is enabled for the domain name. Check whether the CNAME record is in effect

Advanced settings (optional)

After you enable DCDN to accelerate the delivery of content on the ECS instance, you can configure advanced settings based on your business requirements.
ScenarioDescriptionImplementationReferences
Accelerate the delivery of both static and dynamic contentAfter you enable acceleration for dynamic content delivery, DCDN automatically identifies dynamic content and static content. Static content such as images, Sitecore JavaScript SDK (JSS) code, and CSS code is cached on DCDN nodes so that users can retrieve content from the nearest DCDN nodes. For requests that request dynamic content, such as POST requests, DCDN selects an optimal route to redirect the requests to the origin server to retrieve the requested content. Enable acceleration for dynamic content delivery

In the console:

Navigate to the > Acceleration Rules > Dynamic Acceleration page.
Accelerate content delivery in more regionsIf the majority of your users and the ECS instances are located in the Chinese mainland, you can set the accelerated region to Chinese Mainland Only. As your business develops, your users may be located around the world. If requests from your users are all sent to DCDN nodes that are deployed in the Chinese mainland, content delivery can be slow. In this case, you can change the accelerated region to Global. Requests can be scheduled to nodes that are nearest to the users. Change the accelerated regionChange the accelerated region
Balance loads on origin serversDCDN can redirect requests to primary and secondary origin servers based on the round-robin algorithm to balance loads on the origin servers. In addition, DCDN can automatically switch to another origin server when an error occurs on one origin server.
This feature is applicable to the following scenarios:
  • Switch from one ECS instance to another ECS instance that is deployed in a different zone but in the same region. For example, you can switch from an ECS instance in Beijing Zone A to an ECS instance in Beijing Zone B.
  • Switch from one ECS instance to another ECS instance that is deployed in a different region. For example, you can switch from an ECS instance in the China (Beijing) region to an ECS instance in the China (Qingdao) region.
  • Switch from one cloud service provider to another cloud service provider. For example, you can switch from Alibaba Cloud to Tencent Cloud.
  • Switch from cloud services to data centers.
Specify primary and secondary origin serversConfigure an origin server
Meet requirements such as DNS settings, latency, and availabilityYou can enable the IPv6 feature to meet business requirements, including DNS settings, latency, and availability. Enable IPv6Configure IPv6

For more information about DCDN, see What is DCDN?