I want to cache images and other files on my site, so what I did is made sure mod_headers and mod_expires with :-
/usr/sbin/httpd -l
then edited .htaccess to be:-
ExpiresActive On
ExpiresDefault A0
# Set up caching on media files for 1 year (forever?)
<FilesMatch "\.(flv|ico|pdf|avi|mov|ppt|doc|mp3|wmv|wav)$">
ExpiresDefault A29030400
Header append Cache-Control "public"
</FilesMatch>
# Set up caching on media files for 1 week
<FilesMatch "\.(gif|jpg|jpeg|png|swf)$">
ExpiresDefault A604800
Header append Cache-Control "public"
</FilesMatch>
# Set up 2 Hour caching on commonly updated files
<FilesMatch "\.(xml|txt|html|js|css)$">
ExpiresDefault A9200
Header append Cache-Control "proxy-revalidate"
</FilesMatch>
# Force no caching for dynamic files
<FilesMatch "\.(php|htm)$">
ExpiresActive Off
Header set Cache-Control "private, no-cache, no-store, proxy-revalidate, no-transform"
Header set Pragma "no-cache"
</FilesMatch>
<Files 403.shtml>
order allow,deny
allow from all
</Files>
But when I browse the site, every time the images reload and take too much time. Is there anything else I should do?
You do not need cache-control public, or most of the other cache-control settings. Pragma is also old and not really needed. You don't really need any of the php|htm portion. I would say scrap everything from the beginning up to the <files 403.shtml> part and study (and use) the following code below. I would also recommend reading Mark Nottingham's caching tutorial
These bits were taken from html5-boilerplate .htaccess:
# ######################################################################
# # MEDIA TYPES AND CHARACTER ENCODINGS #
# ######################################################################
# ----------------------------------------------------------------------
# | Media types |
# ----------------------------------------------------------------------
# Serve resources with the proper media types (f.k.a. MIME types).
#
# https://www.iana.org/assignments/media-types/media-types.xhtml
# https://httpd.apache.org/docs/current/mod/mod_mime.html#addtype
<IfModule mod_mime.c>
# Data interchange
AddType application/atom+xml atom
AddType application/json json map topojson
AddType application/ld+json jsonld
AddType application/rss+xml rss
AddType application/vnd.geo+json geojson
AddType application/xml rdf xml
# JavaScript
# Normalize to standard type.
# https://tools.ietf.org/html/rfc4329#section-7.2
AddType application/javascript js
# Manifest files
# If you are providing a web application manifest file (see
# the specification: https://w3c.github.io/manifest/), it is
# recommended that you serve it with the `application/manifest+json`
# media type.
#
# Because the web application manifest file doesn't have its
# own unique file extension, you can set its media type either
# by matching:
#
# 1) the exact location of the file (this can be done using a
# directive such as `<Location>`, but it will NOT work in
# the `.htaccess` file, so you will have to do it in the main
# server configuration file or inside of a `<VirtualHost>`
# container)
#
# e.g.:
#
# <Location "/.well-known/manifest.json">
# AddType application/manifest+json json
# </Location>
#
# 2) the filename (this can be problematic as you will need to
# ensure that you don't have any other file with the same name
# as the one you gave to your web application manifest file)
#
# e.g.:
#
# <Files "manifest.json">
# AddType application/manifest+json json
# </Files>
AddType application/x-web-app-manifest+json webapp
AddType text/cache-manifest appcache
# Media files
AddType audio/mp4 f4a f4b m4a
AddType audio/ogg oga ogg opus
AddType image/bmp bmp
AddType image/svg+xml svg svgz
AddType image/webp webp
AddType video/mp4 f4v f4p m4v mp4
AddType video/ogg ogv
AddType video/webm webm
AddType video/x-flv flv
# Serving `.ico` image files with a different media type
# prevents Internet Explorer from displaying then as images:
# https://github.com/h5bp/html5-boilerplate/commit/37b5fec090d00f38de64b591bcddcb205aadf8ee
AddType image/x-icon cur ico
# Web fonts
AddType application/font-woff woff
AddType application/font-woff2 woff2
AddType application/vnd.ms-fontobject eot
# Browsers usually ignore the font media types and simply sniff
# the bytes to figure out the font type.
# https://mimesniff.spec.whatwg.org/#matching-a-font-type-pattern
#
# However, Blink and WebKit based browsers will show a warning
# in the console if the following font types are served with any
# other media types.
AddType application/x-font-ttf ttc ttf
AddType font/opentype otf
# Other
AddType application/octet-stream safariextz
AddType application/x-bb-appworld bbaw
AddType application/x-chrome-extension crx
AddType application/x-opera-extension oex
AddType application/x-xpinstall xpi
AddType text/vcard vcard vcf
AddType text/vnd.rim.location.xloc xloc
AddType text/vtt vtt
AddType text/x-component htc
</IfModule>
# ----------------------------------------------------------------------
# | Reducing MIME type security risks |
# ----------------------------------------------------------------------
# Prevent some browsers from MIME-sniffing the response.
#
# This reduces exposure to drive-by download attacks and cross-origin
# data leaks, and should be left uncommented, especially if the server
# is serving user-uploaded content or content that could potentially be
# treated as executable by the browser.
#
# http://www.slideshare.net/hasegawayosuke/owasp-hasegawa
# http://blogs.msdn.com/b/ie/archive/2008/07/02/ie8-security-part-v-comprehensive-protection.aspx
# https://msdn.microsoft.com/en-us/library/ie/gg622941.aspx
# https://mimesniff.spec.whatwg.org/
<IfModule mod_headers.c>
Header set X-Content-Type-Options "nosniff"
</IfModule>
# ----------------------------------------------------------------------
# | ETags |
# ----------------------------------------------------------------------
# Remove `ETags` as resources are sent with far-future expires headers.
#
# https://developer.yahoo.com/performance/rules.html#etags
# https://tools.ietf.org/html/rfc7232#section-2.3
# `FileETag None` doesn't work in all cases.
<IfModule mod_headers.c>
Header unset ETag
</IfModule>
FileETag None
# ----------------------------------------------------------------------
# | Expires headers |
# ----------------------------------------------------------------------
# Serve resources with far-future expires headers.
#
# (!) If you don't control versioning with filename-based
# cache busting, you should consider lowering the cache times
# to something like one week.
#
# https://httpd.apache.org/docs/current/mod/mod_expires.html
<IfModule mod_expires.c>
ExpiresActive on
ExpiresDefault "access plus 1 month"
# CSS
ExpiresByType text/css "access plus 1 year"
# Data interchange
ExpiresByType application/atom+xml "access plus 1 hour"
ExpiresByType application/rdf+xml "access plus 1 hour"
ExpiresByType application/rss+xml "access plus 1 hour"
ExpiresByType application/json "access plus 0 seconds"
ExpiresByType application/ld+json "access plus 0 seconds"
ExpiresByType application/schema+json "access plus 0 seconds"
ExpiresByType application/vnd.geo+json "access plus 0 seconds"
ExpiresByType application/xml "access plus 0 seconds"
ExpiresByType text/xml "access plus 0 seconds"
# Favicon (cannot be renamed!) and cursor images
ExpiresByType image/vnd.microsoft.icon "access plus 1 week"
ExpiresByType image/x-icon "access plus 1 week"
# HTML
ExpiresByType text/html "access plus 0 seconds"
# JavaScript
ExpiresByType application/javascript "access plus 1 year"
ExpiresByType application/x-javascript "access plus 1 year"
ExpiresByType text/javascript "access plus 1 year"
# Manifest files
ExpiresByType application/manifest+json "access plus 1 year"
ExpiresByType application/x-web-app-manifest+json "access plus 0 seconds"
ExpiresByType text/cache-manifest "access plus 0 seconds"
# Media files
ExpiresByType audio/ogg "access plus 1 month"
ExpiresByType image/bmp "access plus 1 month"
ExpiresByType image/gif "access plus 1 month"
ExpiresByType image/jpeg "access plus 1 month"
ExpiresByType image/png "access plus 1 month"
ExpiresByType image/svg+xml "access plus 1 month"
ExpiresByType image/webp "access plus 1 month"
ExpiresByType video/mp4 "access plus 1 month"
ExpiresByType video/ogg "access plus 1 month"
ExpiresByType video/webm "access plus 1 month"
# Web fonts
# Embedded OpenType (EOT)
ExpiresByType application/vnd.ms-fontobject "access plus 1 month"
ExpiresByType font/eot "access plus 1 month"
# OpenType
ExpiresByType font/opentype "access plus 1 month"
# TrueType
ExpiresByType application/x-font-ttf "access plus 1 month"
# Web Open Font Format (WOFF) 1.0
ExpiresByType application/font-woff "access plus 1 month"
ExpiresByType application/x-font-woff "access plus 1 month"
ExpiresByType font/woff "access plus 1 month"
# Web Open Font Format (WOFF) 2.0
ExpiresByType application/font-woff2 "access plus 1 month"
# Other
ExpiresByType text/x-cross-domain-policy "access plus 1 week"
</IfModule>
Other Boilerplate configurations for various web servers
Server configuration "boilerplates" exist for other HTTP server setups similar to this snippet of Apache configuration and are maintained at https://github.com/h5bp/server-configs
来源：https://stackoverflow.com/questions/9933012/how-to-use-mod-headers-and-mod-expires-to-cache