Edge Acceleration
  • Site Acceleration
    • Overview
    • Quickly Import and Export Site Configuration
    • Access Control
      • Token Authentication
    • Smart Acceleration
    • File Optimization
      • Smart Compression
    • Network Optimization
      • HTTP/2
      • HTTP/3(QUIC)
        • Overview
        • Enable HTTP/3
        • QUIC SDK
          • SDK Overview
          • SDK Download and Integration
          • Sample Code
            • Android
            • iOS
          • API Documentation
            • Android
            • iOS
      • IPv6 Access
      • Maximum Upload Size
      • WebSocket
      • Client IP Geolocation Header
      • Client IP Geographical Location
      • gRPC
    • URL Rewrite
      • Access URL Redirection
      • Origin-Pull URL Rewrite
    • Modifying Header
      • Modifying HTTP Response Headers
      • Modifying HTTP Request Headers
    • Custom Error Page
    • Request and Response Actions
      • Processing order
      • Default HTTP Headers of Origin-Pull Requests
      • Default HTTP Response Headers
    • Media Services
      • Audio and Video Pre-pulling
      • Just-in-Time Image Processing
      • Just-in-Time Media Processing
      • VOD Media Origin
  • L4 Proxy
    • Overview
    • Creating an L4 Proxy Instance
    • Modifying an L4 Proxy Instance
    • Disabling or Deleting an L4 Proxy Instance
    • Batch Configuring Forwarding Rules
    • Obtaining Real Client IPs
      • Obtaining Real TCP Client IPs via TOA
      • Obtaining Real Client IPs Through Protocol V1/V2
        • Overview
        • Method 1: Obtaining Real Client IPs Through Nginx
        • Method 2: Parsing Real Client IPs on Application Server
        • Format of Real Client IPs Obtained Through Proxy Protocol V1/V2
      • Transmitting Client Real IP via SPP Protocol
  • Edge DNS
    • Hosting DNS Records
      • Modifying DNS Servers
      • Configuring DNS Records
      • Advanced DNS Configuration
    • Domain Connection
      • Adding A Domain Name for Acceleration
      • Ownership Verification
      • Modifying CNAME Records
    • Domain alias
      • Overview
      • Configuration Guide
      • Batch Connecting SaaS Domain Names
      • Configuring Alias Domain Names for Disaster Recovery
    • Traffic Scheduling
      • Traffic Scheduling Management
    • Origin Configuration
      • Origin-pull configuration
        • Configuring Origin-Pull HTTPS
        • Host Header Rewrite
        • Controlling Origin-pull Requests
        • Redirect Following During Origin-Pull
        • HTTP/2 Origin-Pull
        • Range GETs
      • Load Balancing
        • Overview
        • Quickly Create Load Balancers
        • Health Check Policies
        • Viewing the Health Status of Origin Server
        • Related References
          • Load Balancing-Related Concepts
          • Introduction to Request Retry Strategy
      • Origin Group Configuration
      • Related References
        • ld Version Origin Group Compatible Related Issues
      • Collect EdgeOne origin-pull node IP
  • Edge Cache
    • Overview
    • EdgeOne Cache Rules
      • Content Cache Rules
      • Cache Key Introduction
      • Vary Feature
    • Cache Configuration
      • Custom Cache Key
      • Node Cache TTL
      • Status Code Cache TTL
      • Browser Cache TTL
      • Offline Caching
      • Cache Prefresh
    • Clear and Preheat Cach
      • Cache Purge
      • URL Pre-Warming
    • How to improve the Cache Hit Rate of EdgeOne
  • Rules Engine
    • Overview
    • Supported Matching Types and Actions
    • Rule Management
    • variables

Default HTTP Response Headers

Overview

This document describes default response headers that EdgeOne passes to the client. These headers follow the origin unless there are custom HTTP headers.





Default HTTP response headers

EdgeOne adds the following default HTTP response headers to responses to the client.

EO-Cache-Status

EO-Cache-Status is used to indicate whether the current Client-initiated requests hit the Cache or not, with the following values:
EO-Cache-Status: HIT: Indicates that the requested resources hit the Cache on the EdgeOne node and the Cache is not expired, directly responded by the node to the user requests.
EO-Cache-Status: MISS: Indicates that the requested resources did not hit the Cache on the EdgeOne node, or hit the Cache but the Cache is expired, the node performs origin-pull verification, the origin file is updated and responded with a 200 status code, the node needs to origin-pull the resources.
EO-Cache-Status: RefreshHit: Indicates that the requested resources hit the Cache on the EdgeOne node, but the Cache is expired, the node performs origin-pull verification, the origin file is not updated and responded with a 304 status code, the node continues to use the Cache to respond to user requests.

Server

This header indicates the server name. The header value depends on the service that the Web Server is built on. By default, this header follows the origin response (if exists). Otherwise, the EdgeOne node adds this header with the value of Server:TencentEdgeOne. For more information, see Server.
Values of Server header for different origin types:
Cloud Object Storage (COS) origin: Server: tencent-cos
Cloud Virtual Machine (CVM) origin: Server: nginx, Server: apache, Server: tomcat, or Server: Microsoft-IIS
Cloud Load Balancer (CLB) origin: Server: openresty

Date

The value of the Date header is the current time of the EdgeOne node server. For more information, please refer to Date.
For instance: Date: Sat, 07 Jan 2023 14:15:52 GMT.

Connection

This header indicates how a persistent connection is handled during the communication between the client and server. By default, this header follows the origin response (if exists). Otherwise, EdgeOne sets the header based on the following rules:
HTTP/2 and QUIC requests: This header is not added.
HTTP 1.0 requests w/o KeepAlive option: The header is set to Connection:close.
**Origin response does not contain content-length and transfer-encoding**: This header is set to Connection:close.
In other cases, the header is set to Connection:keepalive.
For more information, see Connection.

Alt-Svc

Alt-Svc stands for Alternative-Service. It lists the alternative access methods of the site. This header is commonly used for backward compatibility with previous protocols after updating to a new one, such as QUIC. If you enable HTTP/3 (QUIC) for a domain name, this header is added to the HTTP response header by default. For more information, see Alt-Svc.

EO-LOG-UUID

It carries the unique identifier of the request. When an access exception occurs, you can locate the problem by querying logs with this UID.

Example: EO-LOG-UUID: 4105283880544427145.