Apache Reference Manual (6)

KeepAliveTimeout directive
Syntax: KeepAliveTimeout seconds
Default: KeepAliveTimeout 15
Context: server config
Status: Core
Compatibility: KeepAliveTimeout is only available in Apache 1.1 and later.
The number of seconds Apache will wait for a subsequent request before closing the connection. Once a request has been received, the timeout value specified by the Timeout directive applies.
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<Limit> directive
Syntax: <Limit method method ... > ... </Limit>
Context: any
Status: core
Access controls are normally effective for all access methods, and this is the usual desired behaviour. In the general case, access control directives should not be placed within a <limit> section.
The purpose of the <Limit> directive is to restrict the effect of the access controls to the nominated HTTP methods. For all other methods, the access restrictions that are enclosed in the <Limit> bracket will have no effect. The following example applies the access control only to the methods POST, PUT, and DELETE, leaving all other methods unprotected:
<Limit POST PUT DELETE>
require valid-user
</Limit>
The method names listed can be one or more of: GET, POST, PUT, DELETE, CONNECT, OPTIONS, TRACE, PATCH, PROPFIND, PROPPATCH, MKCOL, COPY, MOVE, LOCK, and UNLOCK. The method name is case-sensitive. If GET is used it will also restrict HEAD requests.
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<LimitExcept> directive
Syntax: <LimitExcept method method ... > ... </LimitExcept>
Context: any
Status: core
Compatibility: Available in Apache 1.3.5 and later
<LimitExcept> and </LimitExcept> are used to enclose a group of access control directives which will then apply to any HTTP access method not listed in the arguments; i.e., it is the opposite of a <Limit> section and can be used to control both standard and nonstandard/unrecognized methods. See the documentation for <Limit> for more details.

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