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--- networking:recursive-authoritative [2026/07/22 15:33] – created - external edit 127.0.0.1
+++ networking:recursive-authoritative [2026/07/23 00:36] (current) – removed - external edit (Unknown date) 127.0.0.1
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-====== Recursive Resolver vs Authoritative DNS Server ======
-DNS involves two fundamentally different types of servers:
-  * **Recursive Resolvers**
-  * **Authoritative DNS Servers**
-Although both answer DNS queries, they perform very different roles.
------
-===== Recursive Resolver =====
-A recursive resolver is the DNS server that users query directly.
-Examples include:
-  * Google Public DNS (`8.8.8.8`)
-  * Cloudflare DNS (`1.1.1.1`)
-  * Quad9 (`9.9.9.9`)
-  * Your ISP's DNS servers
-Its responsibilities are:
-  * Receive DNS queries from users.
-  * Search its cache.
-  * Perform recursive lookups if necessary.
-  * Cache the results according to TTL.
-  * Return the final answer to the client.
-<code>
-User
-   │
-   ▼
-Recursive Resolver
-</code>
------
-===== Authoritative DNS Server =====
-An authoritative server stores the official DNS records for a domain.
-Example:
-<code>
-example.com
-      │
-      ▼
-ns1.example.com
-</code>
-It does **not** perform recursive lookups.
-Instead, it simply answers questions about domains for which it is authoritative.
-Typical records include:
-  * A
-  * AAAA
-  * MX
-  * TXT
-  * NS
-  * SOA
-  * CAA
------
-===== Query Flow =====
-Suppose a user requests:
-<code>
-www.example.com
-</code>
-The lookup proceeds as follows:
-<code>
-Browser
-   │
-   ▼
-Recursive Resolver
-   │
-   ▼
-Root Server
-   │
-   ▼
-TLD Server
-   │
-   ▼
-Authoritative Server
-   │
-   ▼
-Answer
-</code>
-The browser communicates only with the recursive resolver.
------
-===== Comparison =====
-^ Recursive Resolver ^ Authoritative Server ^
-| Receives queries from users | Stores official DNS records |
-| Performs recursive lookups | Never performs recursion |
-| Uses cache | Does not cache other domains |
-| Returns cached answers | Returns authoritative answers |
-| Usually operated by ISPs or public DNS providers | Usually operated by DNS hosting providers |
------
-===== Why Responses May Differ =====
-Recursive resolvers may return different answers because:
-  * Their cache has not expired.
-  * They are located in different countries.
-  * CDN or GeoDNS returns different IP addresses.
-  * DNS propagation is still in progress.
-Authoritative servers, however, always return the current published records.
------
-===== Can I Query the Authoritative Server Directly? =====
-Yes.
-For example:
-<code>
-dig @ns1.example.com example.com A
-</code>
-This bypasses recursive resolvers and asks the authoritative server directly.
-This is useful for verifying that recent DNS changes have been published.
------
-===== How Telenegar DNS Check Works =====
-Telenegar DNS Check queries multiple recursive DNS providers around the world.
-This allows you to:
-  * Compare DNS responses.
-  * Detect propagation delays.
-  * Observe GeoDNS behavior.
-  * Compare public DNS providers.
-Telenegar also supports querying authoritative DNS servers directly, allowing you to compare published records with what recursive resolvers currently return.
------
-===== Common Misconceptions =====
-  * **Recursive DNS servers own the DNS records.**
-    * False. They only cache and forward queries.
-  * **Authoritative servers cache Internet DNS records.**
-    * False. They only answer for their own zones.
-  * **Google DNS is authoritative for every domain.**
-    * False. Google Public DNS is only a recursive resolver.
------
-===== Related Topics =====
-  * [[networking:dns|DNS Explained]]
-  * [[networking:dns_propagation|DNS Propagation]]
-  * [[networking:cdn|CDN and GeoDNS]]
-  * [[tools:dnscheck|DNS Check]]
------
-{{tag>dns resolver authoritative recursion nameserver}}