- What's New
- Function Overview
- Service Overview
- Getting Started
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User Guide
- Public Zones
- Private Zones
- Record Sets
- PTR Records
- Intelligent Resolution
- Permissions Management
- Using CTS to Collect DNS Key Operations
- Quota Adjustment
- Change History
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API Reference
- Before You Start
- API Overview
- Calling APIs
- APIs
- Examples
- Permissions Policies and Supported Actions
- Appendix
- Best Practices
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FAQs
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DNS Overview
- Will I Be Billed for the DNS Service?
- How Many Zones, PTR Records, and Record Sets Can I Create?
- What Are Huawei Cloud DNS Servers?
- What Are Huawei Cloud Private DNS Server Addresses?
- What Are the Differences Between Public and Private Domain Names?
- Does DNS Support IPv6?
- Does DNS Support Explicit and Implicit URLs?
- Does DNS Support Dynamic Domain Name Resolution?
- Does DNS Support Wildcard Entries?
- What Is TTL?
- How Many Domain Name Levels Does DNS Support?
- How Are Zones Queried to Resolve a Domain Name?
- What Are the Priorities of Resolution Lines?
- Why Was the Email Address Format Changed in the SOA Record?
- What Is CAA?
- Why Should I Set Priority For an MX Record Set?
- Can DNS Point a Domain Name to a Specific Port?
- Invalid Domain Resolution
- Website Access Failures
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Public Zones
- Why Is a Message Indicating Conflict with an Existing Record Set Displayed When I Add a Record Set?
- How Do I Add Record Sets to Subdomains?
- Which IP Address Is Returned for the Domain Name If There Are Multiple IP Addresses in a Record Set?
- Can I Modify a Zone?
- Can DNS Translate a Domain Name to IP Addresses of On-premises Servers or Third-Party Servers?
- How Can Multiple Domain Names Be Linked to the Same Website?
- How Do I View and Change the DNS Servers of a Domain Name?
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Private Zones
- Why Is a Message Indicating Conflict with an Existing Record Set Displayed When I Add a Record Set?
- How Do I Change Default DNS Servers of an ECS to Huawei Cloud Private DNS Servers?
- How Can I Access an ECS Using Its Host Name?
- How Can I Map the Private IP Address of an ECS to a Domain Name?
- How Can I Use a Private Domain Name to Route Internet Traffic?
- Can I Use Private Domain Names Across Regions?
- Do I Need to Register Private Domain Names?
- Will a Deleted VPC Be Automatically Disassociated from the Private Zone?
- Are Private DNS Server Addresses the Same for All Users?
- What Are the Restrictions on Concurrent Private DNS Requests?
- Reverse Resolution
- Domain Transfer
-
DNS Overview
Show all
What Is TTL?
TTL (time to live) specifies how long records are cached on a local DNS server.
The local DNS server is connected to clients (computers or smartphones) through the Internet. By default, its address is assigned by the broadband carrier. You can also choose a public DNS server, for example, 114.114.114.114 or 8.8.8.8, as your local DNS server.
When receiving requests for a domain name, the local DNS server asks the authoritative DNS server for the required DNS record, and then caches the record for a period of time. During this period, if the local DNS server receives requests for this domain name again, it will not request the record from the authoritative DNS server, but directly returns the cached record.
The time records are cached on the local DNS server is specified by the TTL value. You can set it when adding record sets in public or private zones. For details, see Managing Record Sets.
The effective time of the following operations depends on the TTL value (to accelerate the process, decrease the TTL value):
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