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    Domain Names:FAQ about DNS resolution

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    Domain Names:FAQ about DNS resolution

    Last Updated:Dec 25, 2025

    This topic answers frequently asked questions about DNS resolution.

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    DNS record settings

    Resolution failures/Website inaccessibility

    DNS record settings

    Does DNS resolution support IPv6?

    Yes. You can add AAAA records to point a domain name to an IPv6 address. All Alibaba Cloud DNS name servers are IPv6-enabled.

    How many free DNS records can I add in Alibaba Cloud DNS?

    • Alibaba Cloud DNS supports a maximum of 100,000 DNS records for a primary domain.

    • The Free Edition of Alibaba Cloud DNS allows a maximum of 10 DNS records per hostname (for the same record type and routing policy).

    • The Free Edition supports a maximum of two explicit or implicit URL forwarding records.

    For more information, see Edition comparison.

    What is a TTL value?

    Time to Live (TTL) is the amount of time, in seconds, that a local DNS server is allowed to cache the response for a DNS query.

    Note

    Some local DNS servers may not honor the TTL you set, which can delay the propagation of your DNS changes.

    1. When a local DNS server receives a query, it requests the record from an authoritative name server, such as Alibaba Cloud DNS.

    2. The local DNS server caches the response for the duration specified by the TTL. For any subsequent queries for the same record within this period, the server returns the cached result.

    3. When the TTL expires, the local DNS server removes the cached result. The next query for that record will trigger a new request to the authoritative name server.

    What is the priority of an MX record?

    The priority value determines the order in which mail servers are used. A lower number indicates a higher priority. For example, a server with a priority of 10 will be tried before a server with a priority of 20.

    What is a wildcard DNS record?

    A wildcard DNS record uses an asterisk (*) as the hostname to match requests for any subdomain that does not have an explicitly defined record.

    Assume you create a wildcard A record (such as *.example.com) for your domain name example.com on your name server. Any subdomain that ends in .example.com and does not have a specific DNS record will point to the IP address that you set for the wildcard record. For example:

    • If you set *.example.com to point to 192.0.2.1,

    • then attempts to access any non-existent subdomain such as a.example.com or b.example.com are resolved to 192.0.2.1.

    However, if a subdomain already has a specific DNS record (for example, a.example.com already points to another IP address), a query for that subdomain returns the specifically configured IP address instead of the one in the wildcard record.

    How do I add an SRV record?

    If you use Alibaba Cloud DNS for DNS resolution, see Add an SRV record.

    Can I export DNS records?

    Yes. For more information, see Modify, delete, pause, import, or export DNS records.

    Can I add a URL forwarding record for a domain name?

    Yes. For more information, see Add a URL forwarding record.

    Why is my TXT record verification failing?

    Possible reasons are as follows:

    • Incorrect record value: The TXT record value you added does not exactly match the value required by the service provider. Check for typos or extra characters.

    • Paused record: The DNS record or the entire domain name is paused in the Alibaba Cloud DNS console. Ensure that the record is enabled.

    • Propagation delay: DNS record changes take time to propagate globally. Wait for the record's TTL to expire before you attempt verification.

    Resolution failures/Website inaccessibility

    How do I troubleshoot an inaccessible domain name or website?

    Domain name issues

    The domain name has expired

    • Cause: Your domain name may have expired, which deactivates its DNS records.

    • Solution: Check the domain name's status using a WHOIS lookup tool. If the domain name has expired, you must renew it promptly. After a successful renewal, DNS resolution resumes within 24 to 48 hours.

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    Resolution issues

    The domain name is still inaccessible after renewal

    • Cause: The issue is likely caused by a stale DNS cache.

    • Solution: You can try clearing your browser's cache or using a different browser.

    A "URL forwarding destination not found" error happened

    • Cause 1: Your local resolver may have stale DNS data cached.

      Solution: You can try clearing your browser's cache or using a different browser.

    • Cause 2: There are no DNS records configured for the domain name in the Alibaba Cloud DNS console.

      Solution: You must add a DNS record for the domain name in the Alibaba Cloud DNS console.

    • Cause 3: There is an internal error on the web server that the domain name points to.

      Solution: Contact your hosting provider for assistance.