Configuring the Domain Name Service

Slave mode servers

Any primary, secondary, or caching-only server can operate in slave mode. This type of server always forwards queries it cannot satisfy locally to a fixed list of forwarding servers instead of interacting with the master name servers for the root domain and other zones. The queries to the forwarding servers are recursive, rather than iterative, queries: the queried server either returns the requested data or an error rather than the address of another server that may contain the requested data. There may be one or more forwarding servers, and they are tried in turn until the list is exhausted. A server operating in slave mode never attempts to contact servers other than the forwarders.

A typical scenario would involve a number of workstations and a departmental timesharing machine with Internet access. The workstations might be administratively prohibited from having Internet access. To give the workstations the appearance of access to the Internet domain system, the workstations could be slave servers to the timesharing machine, which would forward the queries and interact with other name servers to resolve the query before returning the answer. An added benefit of using the forwarding feature is that the central machine develops a much more complete cache of information that all the workstations can take advantage of.

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SCO OpenServer Release 5.0.7 -- 11 February 2003