likely degrade performance. Operating System Caching Almost all modern operating systems cache file-data in memory managed directly by the kernel. This is a powerful feature, and for the most part operating header" file, which includes meta- information about the URL, such as when it is due to expire and a ".data" file which is a verbatim copy of the content to be served. In the case of a content negotiated via a ".vary" directory will be created for the URL in question. This directory will have multiple ".data" files corresponding to the differently negotiated content. Maintaining the Disk Cache Although

likely degrade performance. Operating System Caching Almost all modern operating systems cache file-data in memory managed directly by the kernel. This is a powerful feature, and for the most part operating header" file, which includes meta-information about the URL, such as when it is due to expire and a ".data" file which is a verbatim copy of the content to be served. In the case of a content negotiated via a ".vary" directory will be created for the URL in question. This directory will have multiple ".data" files corresponding to the differently negotiated content. Maintaining the Disk Cache Although

likely degrade performance. Operating System Caching Almost all modern operating systems cache file-data in memory managed directly by the kernel. This is a powerful feature, and for the most part operating header" file, which includes meta-information about the URL, such as when it is due to expire and a ".data" file which is a verbatim copy of the content to be served. In the case of a content negotiated via a ".vary" directory will be created for the URL in question. This directory will have multiple ".data" files corresponding to the differently negotiated content. Maintaining the Disk Cache Although

likely degrade performance. Operating System Caching Almost all modern operating systems cache file-data in memory managed directly by the kernel. This is a powerful feature, and for the most part operating header" file, which includes meta-information about the URL, such as when it is due to expire and a ".data" file which is a verbatim copy of the content to be served. In the case of a content negotiated via a ".vary" directory will be created for the URL in question. This directory will have multiple ".data" files corresponding to the differently negotiated content. Maintaining the Disk Cache Although

likely degrade performance. Operating System Caching Almost all modern operating systems cache file-data in memory managed directly by the kernel. This is a powerful feature, and for the most part operating header" file, which includes meta-information about the URL, such as when it is due to expire and a ".data" file which is a verbatim copy of the content to be served. In the case of a content negotiated via a ".vary" directory will be created for the URL in question. This directory will have multiple ".data" files corresponding to the differently negotiated content. Maintaining the Disk Cache Although

overwrite that file with arbitrary data. If the log files themselves are writeable (by a non-root user), then someone may be able to overwrite the log itself with bogus data. 13http://httpd.apache.org/lists operating system environment under which the server itself runs, you must use the standard environment manipulation mechanisms provided by your operating system shell. Setting Environment Variables Related Modules BROWSERMATCHNOCASE PASSENV REWRITERULE SETENV SETENVIF SETENVIFNOCASE UNSETENV Basic Environment Manipulation The most basic way to set an environment variable in Apache is using the unconditional SETENV

likely degrade performance. Operating System Caching Almost all modern operating systems cache file-data in memory managed directly by the kernel. This is a powerful feature, and for the most part operating header" file, which includes meta-information about the URL, such as when it is due to expire and a ".data" file which is a verbatim copy of the content to be served. In the case of a content negotiated via a ".vary" directory will be created for the URL in question. This directory will have multiple ".data" files corresponding to the differently negotiated content. Maintaining the Disk Cache Although

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 537 10.35 Apache Module mod data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 540 10.36 Apache Module loaded, it will now set some default timeouts. • MOD DUMPIO: DUMPIOLOGLEVEL is no longer supported. Data is always logged at LOGLEVEL trace7. 1.1. UPGRADING TO 2.4 FROM 2.2 5 • On Unix platforms, piped now skip compression if it knows that the size overhead added by the compression is larger than the data to be compressed. • Multi-language error documents from 2.2.x may not work unless they are adjusted

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 537 10.35 Apache Module mod data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 540 10.36 Apache Module loaded, it will now set some default timeouts. • MOD DUMPIO: DUMPIOLOGLEVEL is no longer supported. Data is always logged at LOGLEVEL trace7. 1.1. UPGRADING TO 2.4 FROM 2.2 5 • On Unix platforms, piped now skip compression if it knows that the size overhead added by the compression is larger than the data to be compressed. • Multi-language error documents from 2.2.x may not work unless they are adjusted

loaded, it will now set some default timeouts. mod_dumpio: DumpIOLogLevel is no longer supported. Data is always logged at LogLevel trace7. On Unix platforms, piped logging commands configured using either now skip compression if it knows that the size overhead added by the compression is larger than the data to be compressed. Multi-language error documents from 2.2.x may not work unless they are adjusted mod_buffer Provides for buffering the input and output filter stacks mod_data Convert response body into an RFC2397 data URL mod_ratelimit Provides Bandwidth Rate Limiting for Clients mod_request