This topic describes the causes of unexpected high bills and the solutions to them. If your domain name is vulnerable to attacks or is abused for data transmission, high bandwidth values or traffic spikes may occur. In this case, you may receive bills that are higher than expected.

Potential risks: high bills caused by attacks or attack-like activities

  • If an attack occurs, you are charged for the bandwidth resources of Alibaba Cloud CDN and data transfer.
  • If your domain name is abused for data transmission, high bandwidth values or traffic spikes may occur. This is similar to an attack, and you are charged for bandwidth resources and data transfer.

Potential consequences: bills that are higher than expected

If your domain name is under attack or abused for data transmission, the bills may be higher than expected and your account balance may be exhausted.

Alibaba Cloud CDN uses the pay-as-you-go billing method. In some cases, Alibaba Cloud CDN may not be suspended when the account balance reaches 0 due to different billing cycles (by hour, by day, or by month) or bill delays. Overdue payments may occur, including those whose amount due is higher than the value specified in the grace period policy.

Alibaba Cloud CDN supports grace periods. If you have a grace period configured, Alibaba Cloud CDN is not suspended before the grace period ends. The grace period is determined based on your account credibility and purchase history. You can set the grace period to a period of time. The grace period is reset every month.

Solutions

To ensure that Alibaba Cloud CDN runs as expected and prevent unexpected high bills, we recommend that you enable security features to manage network traffic. For more information, see the product page of Anti-DDoS.

The following table lists the features that can be used to manage network traffic.
Feature Description
Bandwidth cap If you want to limit the amount of bandwidth resources that a domain name can consume, you can set a bandwidth cap for the domain name. After a bandwidth value reaches the specified bandwidth cap, Alibaba Cloud CDN disables acceleration for the domain name and requests destined for the domain name are directly sent to the origin server. For more information, see Configure a bandwidth cap.
Bandwidth throttling If your daily peak bandwidth of greater than 10 Gbit/s can be met and you want to throttle bandwidth for Alibaba Cloud CDN, you can submit a ticket.
Notice After a bandwidth value reaches the specified threshold, users access your website slower than before and packet loss may occur.
Real-time monitoring If you want to monitor the peak bandwidth values of a domain name in real time, you can use CloudMonitor. After a bandwidth value reaches the specified threshold, notifications are sent to the administrator of your Alibaba Cloud CDN service through text messages, emails, or DingTalk messages. This alerts you of potential risks. For more information, see the product page of CloudMonitor.
Spending management and alerts You can use the following features to monitor and control the expenses of your Alibaba Cloud CDN service. To configure these features, move your pointer over Expenses in the top navigation bar of the console and select User Center.
  • Low balance alert: After this feature is enabled, notifications are sent to you through text messages if the balance in your Alibaba Cloud account drops below a specified value.
  • Grace period: After this feature is disabled, Alibaba Cloud CDN stops running immediately after an overdue payment occurs. This prevents high overdue payments.
  • High bill alert: After this feature is enabled, notifications are sent to you through text messages if a daily bill reaches a specified amount.
Note To ensure the integrity of the statistics and the accuracy of the bills, Alibaba Cloud CDN issues the bill about three hours after a billing cycle ends. Therefore, the time when the relevant fees are deducted from your account balance may be later than the time when the resources are consumed within the billing cycle. Alibaba Cloud does not provide consumption details of CDN resources in bills because Alibaba Cloud CDN is a distributed service. Other CDN providers adopt similar approaches.