Microsoft windows 2000 DNS manual Using Global Suffix Search Order, Unqualified Single-Label Query

Models: windows 2000 DNS

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Unqualified Single-Label Query

resolution. The following summarizes the name resolution algorithm:

The query is issued to the lead server on the preferred adapter's server list.

If no response was received within a one second interval, the query is issued to the lead server(s) on all lists, including the one on the preferred adapter.

If no response was received within a two second interval, the query is issued to all DNS servers on all lists, including the lead servers queried before.

If no response was received within a two second interval, once again the query is issued to all DNS servers on all lists.

This procedure will be repeated after 4 seconds, and later after 8 seconds if no response is received.

If the query is not resolved after all listed attempts (they may take up to seventeen seconds), then a timeout is returned to the client.

The algorithm is modified if some response(s) was received:

If a positive response is received from a server, the response is returned to the caller and the algorithm stops

If a negative response is received from a server, the list that server belongs to is removed from this query.

If a server on every adapter list returns a negative response, then a negative response is returned to the caller.

If a server returns a server failure, then that server is removed from the query for a certain period of time as described in the “DNS Server List Management” section.

Unqualified Single-Label Query

A name containing no dots is called an Unqualified Single-Label name, for example ntserver.

If such a name needs to be resolved it must be fully-qualified using some suffix before being placed on the wire. The list of suffixes to try can come from two places:

Global suffix search order, and

Primary and per-adapter domain names.

If a suffix search order is predefined, then it is used. If it is not defined then the Primary and per-adapter domain names are used.

Using Global Suffix Search Order

The global suffix search order is set by means of the TCP/IP configuration User Interface. It is not a per-adapter value. Suffixes are appended in the order given in the user interface.

The name concatenation algorithm in a name resolution process is as follows:

The first suffix in the search order is appended to the name.

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Microsoft windows 2000 DNS manual Using Global Suffix Search Order, Unqualified Single-Label Query