Feedback will be sent to Microsoft: By pressing the submit button, your feedback will be used to improve Microsoft products and services. Privacy policy. Check whether the DNS server is authoritative for the name that is being looked up.
If so, see Checking for problems with authoritative data. If you get a failure or time-out response, see Checking for recursion problems. Flush the resolver cache. To do this, run the following command in an administrative Command Prompt window:.
If the resolver returns a "Server failure" or "Query refused" response, the zone is probably paused, or the server is possibly overloaded. You can learn whether it's paused by checking the General tab of the zone properties in the DNS console. If the resolver returns a "Request to server timed out" or "No response from server" response, the DNS service probably is not running. Try to restart the DNS Server service by entering the following at a command prompt on the server:.
If the issue occurs when the service is running, the server might not be listening on the IP address that you used in your nslookup query. On the Interfaces tab of the server properties page in the DNS console, administrators can restrict a DNS server to listen on only selected addresses.
If the DNS server has been configured to limit service to a specific list of its configured IP addresses, it's possible that the IP address that's used to contact the DNS server is not in the list. You can try a different IP address in the list or add the IP address to the list. In rare cases, the DNS server might have an advanced security or firewall configuration. If the server is located on another network that is reachable only through an intermediate host such as a packet filtering router or proxy server , the DNS server might use a non-standard port to listen for and receive client requests.
Therefore, if the DNS server uses any other port, nslookup queries fail. If you think that this might be the problem, check whether an intermediate filter is intentionally used to block traffic on well-known DNS ports.
Check whether the server that returns the incorrect response is a primary server for the zone the standard primary server for the zone or a server that uses Active Directory integration to load the zone or a server that's hosting a secondary copy of the zone.
Specifies a DNS server. Cache locking is configured as a percent value. For example, if the cache locking value is set to 50, the DNS server does not overwrite a cached entry for half of the duration of the TTL. By default, the cache locking percent value is Specifies how long 1 to seconds an entry that records a negative answer to a query remains stored in the DNS cache. The value must be provided as a TimeSpan.
The default setting is 15 minutes. Specifies how long 0 to seconds a record is saved in cache. The default setting is one day 86, seconds. Returns an object representing the item with which you are working. By default, this cmdlet does not generate any output. Already a Member? Join your peers on the Internet's largest technical computer professional community.
It's easy to join and it's free. Register now while it's still free! Already a member? Close this window and log in. Join Us Close. Join Tek-Tips Forums! Join Us! By joining you are opting in to receive e-mail. Promoting, selling, recruiting, coursework and thesis posting is forbidden. Students Click Here. We have a Fileserver that does an automatic DNS failure to a disaster recovery if it goes down. On a network capture, we would see the following Network Monitor output note Similar to forwarders, there are two key variables for Conditional Forwarders.
We still have RecursionTimeout which is operating at server level but in this scenario we are using ForwarderTimeout instead of ForwardingTimeout.
Specifically note that ForwarderTimeout is operating on a zone basis and has different default values:. Since Conditional Forwarders are configured for specific zones, the ForwarderTimeout is zone-dependent as well. When the DNS server receives a query for a record in a zone that it is not authoritative for, and is configured to use Conditional Forwarders for it, the default behavior is the following:. In addition to the configured delay there can be an additional half second delay due to system overhead.
We don't send the Server Failure immediately after the RecursionTimeout expiration, but only when it is the time to try the next conditional forwarder.
This means that with default settings, a R2 server will be able to query at most 2 conditional forwarders. There will not be enough time to arrive to use the third conditional forwarder. At the eighth second, RecursionTimeout expires so we'll not reach the point where the third conditional forwarder is queried which would have happened after 5.
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