This topic describes how to adjust the bandwidth of an ApsaraDB for Redis instance. If the bandwidth of an instance is insufficient to handle unexpected or scheduled traffic spikes, such as traffic spikes in a flash sale, you can increase the bandwidth of the instance without changing the instance specifications. This allows you to focus on business growth.

Prerequisites

  • The instance uses local disks.
  • The instance is a Community Edition instance or a DRAM-based instance of the ApsaraDB for Redis Enhanced Edition (Tair). For more information about DRAM-based instances, see DRAM-based instances.

Scenarios

The bandwidth of an instance varies based on the instance type. If the traffic of an instance reaches the allocated bandwidth, network congestion may occur and instance performance may deteriorate. In the following scenarios, you can adjust the bandwidth of an instance to prevent network congestion and performance deterioration on the instance. A bandwidth adjustment helps you increase bandwidth at a lower cost than an instance specification change and can prevent transient connections.

Note
  • We recommend that you use the bandwidth auto scaling feature. When the bandwidth usage of an instance reaches a specified threshold, the bandwidth is automatically increased or decreased. This feature reduces costs and facilitates O&M. For more information, see Enable bandwidth auto scaling.
  • If the instance is a Community Edition instance that requires a sharp bandwidth increase, we recommend that you change the instance into an Enhanced Edition (Tair) instance. This is because a Tair instance can support a bandwidth of 96 Mbit/s or more.
Scenario Description
Handle traffic spikes You can adjust the bandwidth of the instance to handle traffic spikes during promotional events such as a flash sale. After these events end, you can decrease the bandwidth of the instance to reduce costs.
Mitigate impacts on your business If a large number of read and write operations are performed on large keys within a short period of time, you must temporarily increase the bandwidth of the instance to mitigate impacts on your business and to reserve time to process these operations.
Deal with skewed requests at low costs If the instance is a cluster or read/write splitting instance, some data shards or read replicas of the instance are frequently accessed. As a result, the bandwidth usages of these data shards or read replicas frequently reach the allocated bandwidths. However, the bandwidth usages of other data shards or read replicas are low. In this case, you can increase the bandwidths of specific data shards or read replicas instead of increasing the bandwidth or changing the specifications of the instance. For more information about cluster and read/write splitting instances, see Cluster master-replica instances and Read/write splitting instances.
Increase the bandwidth of a standard instance If the instance is a standard instance of the highest specifications and the bandwidth of the instance does not meet your business requirements, you can increase the bandwidth of the instance without the need to upgrade the instance to a cluster instance. This allows you to focus on business improvements. For more information about standard instances, see Standard master-replica instances.

Limits

  • The bandwidth of an instance can be increased to up to three times the bandwidth that is provided for the instance type. If you require higher bandwidth for an instance, you can change the specifications of the instance or upgrade the instance from a standard instance to a cluster instance, and then adjust the instance bandwidth.
    Note
    • For more information about the bandwidths that are supported by different instance types, see Overview.
    • If you change the architecture of an instance, such as from standard to cluster, you can no longer use the bandwidth auto scaling feature.
  • If you perform the following operations on an instance, the extra bandwidth that you purchased becomes invalid and you receive a refund. You must re-adjust the instance bandwidth based on your business requirements. By default, the adjusted bandwidth inherits the expiration time of the previously purchased extra bandwidth.
    Operation Exception
    Upgrade the major version None
    Change the configurations of an instance If the instance is a standard instance, the bandwidth settings remain valid after you upgrade the specifications of the instance.
    Migrate an instance across zones If the instance is a standard instance, the bandwidth settings remain valid.

Billing

You are charged per day based on the amount and usage duration of the extra bandwidth that you purchase. The fees vary based on the region that you select. For more information, see Billable items.

Note You are not charged for the bandwidth that is provided for the instance type. You are charged only for the extra bandwidth that you purchase.

Procedure

  1. Log on to the ApsaraDB for Redis console and go to the Instances page. In the top navigation bar, select the region in which the instance is deployed. Then, find the instance and click its ID.
  2. In the Basic Information section, click Modify to the right of Maximum Internal Bandwidth.
    Note
    • In the Basic Information section, you can view the maximum internal bandwidth of the instance. If the instance is a cluster instance or a read/write splitting instance, the bandwidth is the sum of the bandwidths that are allocated to all data nodes within the instance.
    • During off-peak hours, you can reduce the bandwidth to save resources and reduce costs. For more information about how to view the traffic usage of an instance, see View monitoring data.
  3. In the panel that appears, specify the amount and subscription duration of the extra bandwidth that you want to purchase.
    Configuration item Description
    Bandwidth

    Select the extra bandwidth that you want to purchase. The bandwidth of an instance can be increased to up to three times the bandwidth that is provided for the instance type. For more information about the bandwidths that are provided for various instance types, see Overview. The maximum extra bandwidth that you can select varies based on the instance type.

    • If the instance is a standard instance, adjust the bandwidth of the instance.
    • If the instance is a cluster or read/write splitting instance, select one of the following options:
      • Total Shard Bandwidth: allows you to adjust the bandwidths of all data shards within the instance at the same time. For example, if you want to handle traffic spikes during activities such as flash sales, you can select this option to increase bandwidths, instead of changing the specifications of the instance.
      • Selected Shard Bandwidth: allows you to adjust the bandwidths of one or more specific data shards. For example, if you want to handle request skew issues, you can select this option to adjust the bandwidths of the selected shads based on how requests are skewed.
        Note

        You can use the diagnostic report feature to analyze whether an instance receives skewed requests. For more information, see Create a diagnostic report.

    Auto-Renew Specify whether to enable auto-renewal. If auto-renewal is enabled, the renewal cycle is fixed to one month.
    Duration Select a subscription duration. The maximum subscription duration spans five years.
    Note If the previously purchased extra bandwidth has not expired, the subscription duration of the previously purchased extra bandwidth is inherited and this option is not displayed.
  4. Click Pay and complete the payment.
    After you complete the payment, wait for about 1 minute. Then, the maximum internal bandwidth of the instance is updated to the sum of the existing bandwidth and the purchased extra bandwidth, and the expiration time of the extra bandwidth is displayed.
    Note You can click the Renewal icon next to the expiration time of the extra bandwidth to increase the subscription duration.

FAQ

  • Q: Can I adjust the bandwidth of a specific data shard or data node within a cluster instance or a read/write splitting instance?

    A: Yes, you can adjust the bandwidth of a specific data shard or data node within a cluster instance or a read/write splitting instance based on your business requirements. This way, you can handle skewed requests with more flexibility.

  • Q: Does a bandwidth adjustment cause transient connections?

    A: No, a bandwidth adjustment immediately takes effect and does not cause transient connections.

  • Q: If I purchase a specific amount of extra bandwidth at 15:00 on March 1, 2021 and select a one-day subscription duration, when does the extra bandwidth that I purchase expire?

    A: The extra bandwidth that you purchase expires at 00:00 on March 3, 2021. You are not charged for the usage of the extra bandwidth on March 1, 2021.

  • Q: How do I unsubscribe from the extra bandwidth that I purchase for my instance?
    A: Move the bandwidth adjustment slider to the leftmost position to decrease the bandwidth of your instance to the value provided for the instance type. Then, check the refund to your Alibaba Cloud account and complete the payment.
    Note You can go to the Orders page to view the progress of the order.
  • Q: My subscription instance has expired, and I do not plan to renew the instance. If the extra bandwidth that I purchased does not expire until next month, can I receive a refund?

    A: Yes, after your instance is stopped, you will receive a refund based on the remaining subscription duration of the extra bandwidth that you purchased. If the extra bandwidth that you purchased expires before the instance, Alibaba Cloud sends you a notification. This helps prevent the impacts of bandwidth changes on your business.

  • Q: How do I check whether auto-renewal is enabled for the extra bandwidth that I purchased for my instance?

    A: Go to the Renewal page. Then, enter the ID of your instance and the -bw suffix in the Instance ID field and click Search. Example: r-bp1zxszhcgatnx****-bw.

  • Q: If I change the specifications of my instance after I purchase a specific amount of extra bandwidth, am I still charged for the extra bandwidth?

    A: Yes, if you change the specifications of your instance after you purchase a specific amount of extra bandwidth, the extra bandwidth remains valid and you are charged for the extra bandwidth. The bandwidth of your instance is the sum of the bandwidth that is provided for the new instance type and the extra bandwidth that you purchase. These rules apply only to standard instances. For other instance architectures, the extra bandwidth that you purchase becomes invalid and you receive a refund after you change the specifications of your instance. In this case, you must adjust the bandwidth of the instance again if needs arise.

    Note For more information about the bandwidths that are supported by different instance types, see Overview.

Related API operations

Operation Description
EnableAdditionalBandwidth Adjusts the bandwidth of an ApsaraDB for Redis instance.