- Release Notes and Announcements
- CLB Release Notes
- [April 15, 2024] Domain Name Upgrade for Domain Name-based Public Network CLB
- [July 25, 2023] Adding Rate Limits on Shared CLB Instances
- [July 3, 2023] CLB API Authentication Upgrade
- [June 9, 2023] Adjusting the Grace Period for Pay-as-you-go CLB Instances
- [March 6, 2023] Launching Domain Name-Based Public CLBs
- [Feb. 24, 2023] Changing Health Check Source IP to 100.64.0.0/10 IP Range
- [July 8, 2022] Classic CLB Upgrade Prompt
- 【October 20, 2021】Classic CLB End-of-Sale Notice
- 【April 27, 2021】Announcement on the Authentication Upgrade for Certain CLB APIs
- Product Introduction
- Purchase Guide
- Getting Started
- Directions
- CLB Instance
- Directions for Upgrading to Domain Name-Based CLB
- Creating CLB Instances
- Creating an IPv6 CLB Instance
- Creating IPv6 NAT64 CLB Instances
- Creating an Anycast CLB Instance
- Configure CLB Forwarding Domain Name
- Configuring CLB Security Group
- Binding Private Network CLB to EIP
- Enabling or Disabling a CLB Instance
- Cloning CLB Instances
- Exporting CLB Instances
- Upgrade to a LCU-supported instances
- Adjusting Specification of LCU-supported CLBs
- Deleting CLB Instances
- Releasing Idle CLB Instances
- Configuring Deletion Protection
- Adjusting Instance Public Network Configurations
- CLB Listener
- CLB Listener Overview
- Configuring TCP Listener
- Configuring a UDP Listener
- Configuring TCP SSL Listener
- Configuring a QUIC Listener
- Configuring an HTTP Listener
- Configuring HTTPS Listener
- Load Balancing Methods
- Session Persistence
- Layer-7 Redirection Configuration
- Layer-7 Custom Configuration
- Layer-7 Domain Name Forwarding and URL Rules
- Using QUIC Protocol on CLB
- SNI Support for Binding Multiple Certificates to a CLB Instance
- Configuring gRPC Support for Layer-7 Protocols
- Real Server
- Health Check
- Certificate Management
- Log Management
- Monitoring and Alarm
- Cloud Access Management
- Classic CLB
- CLB Instance
- Best Practices
- Enabling Gzip Compression & Testing
- HTTPS Forwarding Configurations
- Obtaining Real Client IPs
- Best Practices for Configuring Load Balancing Monitoring Alerts
- Implementing HA Across Multiple AZs
- Load Balancing Algorithm Selection and Weight Configuration Examples
- Configuring WAF protection for CLB listening domain names
- Ops Guide
- Troubleshooting
- API Documentation
- History
- Introduction
- API Category
- Making API Requests
- Instance APIs
- Listener APIs
- Backend Service APIs
- Target Group APIs
- Redirection APIs
- Other APIs
- ModifyLoadBalancersProject
- InquiryPriceCreateLoadBalancer
- InquiryPriceModifyLoadBalancer
- InquiryPriceRenewLoadBalancer
- DescribeLoadBalancerTraffic
- DescribeTaskStatus
- DescribeClsLogSet
- CreateClsLogSet
- CreateTopic
- CreateLoadBalancerSnatIps
- DeleteLoadBalancerSnatIps
- SetLoadBalancerSecurityGroups
- SetSecurityGroupForLoadbalancers
- ReplaceCertForLoadBalancers
- DescribeLoadBalancerListByCertId
- SetLoadBalancerClsLog
- DescribeQuota
- DescribeResources
- Classic CLB APIs
- Load Balancing APIs
- Data Types
- Error Codes
- CLB API 2017
- FAQs
- Service Level Agreement
- Contact Us
- Glossary
- Release Notes and Announcements
- CLB Release Notes
- [April 15, 2024] Domain Name Upgrade for Domain Name-based Public Network CLB
- [July 25, 2023] Adding Rate Limits on Shared CLB Instances
- [July 3, 2023] CLB API Authentication Upgrade
- [June 9, 2023] Adjusting the Grace Period for Pay-as-you-go CLB Instances
- [March 6, 2023] Launching Domain Name-Based Public CLBs
- [Feb. 24, 2023] Changing Health Check Source IP to 100.64.0.0/10 IP Range
- [July 8, 2022] Classic CLB Upgrade Prompt
- 【October 20, 2021】Classic CLB End-of-Sale Notice
- 【April 27, 2021】Announcement on the Authentication Upgrade for Certain CLB APIs
- Product Introduction
- Purchase Guide
- Getting Started
- Directions
- CLB Instance
- Directions for Upgrading to Domain Name-Based CLB
- Creating CLB Instances
- Creating an IPv6 CLB Instance
- Creating IPv6 NAT64 CLB Instances
- Creating an Anycast CLB Instance
- Configure CLB Forwarding Domain Name
- Configuring CLB Security Group
- Binding Private Network CLB to EIP
- Enabling or Disabling a CLB Instance
- Cloning CLB Instances
- Exporting CLB Instances
- Upgrade to a LCU-supported instances
- Adjusting Specification of LCU-supported CLBs
- Deleting CLB Instances
- Releasing Idle CLB Instances
- Configuring Deletion Protection
- Adjusting Instance Public Network Configurations
- CLB Listener
- CLB Listener Overview
- Configuring TCP Listener
- Configuring a UDP Listener
- Configuring TCP SSL Listener
- Configuring a QUIC Listener
- Configuring an HTTP Listener
- Configuring HTTPS Listener
- Load Balancing Methods
- Session Persistence
- Layer-7 Redirection Configuration
- Layer-7 Custom Configuration
- Layer-7 Domain Name Forwarding and URL Rules
- Using QUIC Protocol on CLB
- SNI Support for Binding Multiple Certificates to a CLB Instance
- Configuring gRPC Support for Layer-7 Protocols
- Real Server
- Health Check
- Certificate Management
- Log Management
- Monitoring and Alarm
- Cloud Access Management
- Classic CLB
- CLB Instance
- Best Practices
- Enabling Gzip Compression & Testing
- HTTPS Forwarding Configurations
- Obtaining Real Client IPs
- Best Practices for Configuring Load Balancing Monitoring Alerts
- Implementing HA Across Multiple AZs
- Load Balancing Algorithm Selection and Weight Configuration Examples
- Configuring WAF protection for CLB listening domain names
- Ops Guide
- Troubleshooting
- API Documentation
- History
- Introduction
- API Category
- Making API Requests
- Instance APIs
- Listener APIs
- Backend Service APIs
- Target Group APIs
- Redirection APIs
- Other APIs
- ModifyLoadBalancersProject
- InquiryPriceCreateLoadBalancer
- InquiryPriceModifyLoadBalancer
- InquiryPriceRenewLoadBalancer
- DescribeLoadBalancerTraffic
- DescribeTaskStatus
- DescribeClsLogSet
- CreateClsLogSet
- CreateTopic
- CreateLoadBalancerSnatIps
- DeleteLoadBalancerSnatIps
- SetLoadBalancerSecurityGroups
- SetSecurityGroupForLoadbalancers
- ReplaceCertForLoadBalancers
- DescribeLoadBalancerListByCertId
- SetLoadBalancerClsLog
- DescribeQuota
- DescribeResources
- Classic CLB APIs
- Load Balancing APIs
- Data Types
- Error Codes
- CLB API 2017
- FAQs
- Service Level Agreement
- Contact Us
- Glossary
Product Introduction
Product Purchase
Product Implementation
What is HTTP/2?
HTTP/2 (Hypertext Transfer Protocol Version 2) is a major revision of the HTTP network protocol used by the World Wide Web.
HTTP/2 is designed to address the performance issues in HTTP1.X to better use network resources and reduce network application latency.
HTTP/2 is backward compatible with HTTP1.X.
Why should I use HTTP/2?
Compared with HTTP1.X, HTTP/2 can make the response be more fast and efficient. HTTP/2 has the following advantages:
Multiplex: concurrent processing brings a faster response.
Server push: the server proactively pushes resources needed by the client, reducing the number of requests.
More features include bandwidth limit, request priority, header compression, and binary framing.
How does the billing work?
CLB supports the HTTP/2 protocol without charging extra fees.
How do I enable HTTP/2 on CLB?
Note：
The HTTP listener does not support HTTP/2. Mainstream browsers and web servers only support the TLS-based HTTP/2 protocol.
The HTTP1.X protocol is still used between the CLB instance and the real server.
1. Enable HTTP/2 on HTTPS listeners
CLB instance: you can enable or disable the HTTP/2 protocol in a CLB instance. For more information, please see Configuring an HTTPS Listener.
Classic CLB instance: HTTPS listeners created for a classic CLB instance before April 2018 do not support HTTP/2. HTTPS listeners created after April 2018 support but cannot disable HTTP/2.
2. Agree on the protocol at client access
When the client accesses an HTTP/2-enabled listener, the protocol version will be negotiated during the handshake process of HTTPS. The client uses ALPN (Application-Layer Protocol Negotiation) to inform the server of a list of supported protocols. The server selects HTTP/2 or HTTP1.X according to the protocol list. If the client does not support HTTP/2, the server will be automatically backward compatible without requiring additional configuration.
Which regions support HTTP/2?
Currently, all regions support HTTP/2.
Yes
No
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