Apache httpd 2.2 default layout (apache.org source package):
ServerRoot :: /usr/local/apache2
DocumentRoot :: /usr/local/apache2/htdocs
Apache Config File :: /usr/local/apache2/conf/httpd.conf
Other Config Files :: /usr/local/apache2/conf/extra/
SSL Config File :: /usr/local/apache2/conf/extra/httpd-ssl.conf
ErrorLog :: /usr/local/apache2/logs/error_log
AccessLog :: /usr/local/apache2/logs/access_log
cgi-bin :: /usr/local/apache2/cgi-bin (enabled by default, but the bundled scripts are 644)
binaries (apachectl) :: /usr/local/apache2/bin
start/stop :: /usr/local/apache2/bin/apachectl (start|restart|graceful|graceful-stop|stop|configtest)
Apache httpd 2.0 default layout (apache.org source package):
ServerRoot :: /usr/local/apache2
DocumentRoot :: /usr/local/apache2/htdocs
Apache Config File :: /usr/local/apache2/conf/httpd.conf
SSL Config :: /usr/local/apache2/conf/ssl.conf
ErrorLog :: /usr/local/apache2/logs/error_log
AccessLog :: /usr/local/apache2/logs/access_log
cgi-bin :: /usr/local/apache2/cgi-bin (enabled by default, but the bundled scripts are 644)
binaries (apachectl) :: /usr/local/apache2/bin
start/stop :: /usr/local/apache2/bin/apachectl (start|stop|graceful|configtest)
Debian, Ubuntu (Apache httpd 2.x):
ServerRoot :: /etc/apache2
DocumentRoot :: /var/www
Apache Config Files :: /etc/apache2/apache2.conf
:: /etc/apache2/ports.conf
Default VHost Config :: /etc/apache2/sites-available/default, /etc/apache2/sites-enabled/000-default
Module Locations :: /etc/apache2/mods-available, /etc/apache2/mods-enabled
ErrorLog :: /var/log/apache2/error.log
AccessLog :: /var/log/apache2/access.log
cgi-bin :: /usr/lib/cgi-bin
binaries (apachectl) :: /usr/sbin
start/stop :: /etc/init.d/apache2 (start|stop|restart|reload|force-reload|start-htcacheclean|stop-htcacheclean)
Fedora Core, CentOS, RHEL:
ServerRoot :: /etc/httpd
Primary Config Fle :: /etc/httpd/conf/httpd.conf
Other Config Files :: /etc/httpd/conf.d
Module Locations :: /usr/lib/httpd/modules
DocumentRoot :: /var/www/html
ErrorLog :: /var/log/httpd/error_log
AccessLog :: /var/log/httpd/access_log
cgi-bin :: /var/www/cgi-bin (empty and disabled by default)
binary :: /usr/sbin/httpd
runtime directory :: /etc/httpd/run
start/stop :: /sbin/service httpd {start|stop|restart|condrestart|reload|status|fullstatus|graceful|help|configtest}
RedHat 9.0 and older:
ServerRoot :: /etc/httpd
Primary Config Fle :: /etc/httpd/conf/httpd.conf
DocumentRoot :: /var/www/html
ErrorLog :: /var/log/httpd/error_log
AccessLog :: /var/log/httpd/access_log
cgi-bin :: /var/www/cgi-bin (empty and disabled by default)
binary :: /usr/sbin/httpd
start/stop :: /sbin/service httpd {start|stop|restart|condrestart|reload|status|fullstatus|graceful|help|configtest}
Mandriva (Apache httpd 2.2):
ServerRoot :: /etc/httpd
Primary Config Fle :: /etc/httpd/conf/httpd.conf
DocumentRoot :: /var/www/html
ErrorLog :: /var/log/httpd/error_log
AccessLog :: /var/log/httpd/access_log
cgi-bin :: /var/www/cgi-bin
binary :: /usr/sbin/httpd
start/stop :: /sbin/service httpd
{start|stop|restart|reload|graceful|condreload|closelogs|update|condrestart|status|
extendedstatus|configtest|configtest_vhosts|semcleanrestart|debug|show_defines}
Mac OS X (Leopard, Apache httpd 2.2):
ServerRoot :: /usr
Primary Config Fle :: /etc/apache2/httpd.conf
DocumentRoot :: /Library/WebServer/Documents
ErrorLog :: /var/log/apache2/error_log
AccessLog :: /var/log/apache2/access_log
cgi-bin :: /Library/WebServer/CGI-Executables (empty by default)
binary :: /usr/sbin/httpd
start/stop :: /usr/sbin/apachectl (start|stop|restart|fullstatus|status|graceful|graceful-stop|configtest|help)
NetBSD Apache httpd 2.0 and 1.3 from pkgsrc (layout is identical):
ServerRoot :: /usr/pkg
Config File :: /usr/pkg/etc/httpd/httpd.conf
DocumentRoot :: /usr/pkg/share/httpd/htdocs
ErrorLog :: /var/log/httpd/error_log
AccessLog :: /var/log/httpd/access_log
cgi-bin :: /usr/pkg/libexec/cgi-bin
binaries (apachectl) :: /usr/pkg/sbin
start/stop :: /etc/rc.d/apache [fast|force|one](start stop restart rcvar reload status poll)
/etc/rc.conf variables :: apache=YES, apache_start="start" (or "startssl")
FreeBSD 6.1 (Apache httpd 2.2):
ServerRoot :: /usr/local
Config File :: /usr/local/etc/apache22/httpd.conf
DocumentRoot :: /usr/local/www/apache22/data
ErrorLog :: /var/log/httpd-error.log
AccessLog :: /var/log/httpd-access.log
cgi-bin :: /usr/local/www/apache22/cgi-bin
binaries (apachectl) :: /usr/local/sbin
start/stop :: /usr/local/etc/rc.d/apache22.sh (start|restart|stop|reload|graceful|gracefulstop|configtest)
/etc/rc.conf variables :: apache22_enable="YES"
FreeBSD 6.1 (Apache httpd 2.0):
ServerRoot :: /usr/local
Config File :: /usr/local/etc/apache2/httpd.conf
DocumentRoot :: /usr/local/www/data
ErrorLog :: /var/log/httpd-error.log
AccessLog :: /var/log/httpd-access.log
cgi-bin :: /usr/local/www/cgi-bin
binaries (apachectl) :: /usr/local/sbin
start/stop :: /usr/local/etc/rc.d/apache2.sh [fast|force|one](start|restart|stop|reload|configtest|rcvar)
/etc/rc.conf variables :: apache2_enable="YES"
Win32 (Apache httpd 2.2):
ServerRoot :: "C:/Program Files/Apache Software Foundation/Apache2.2"
Config File :: "C:/Program Files/Apache Software Foundation/Apache2.2/conf/httpd.conf"
DocumentRoot :: "C:/Program Files/Apache Software Foundation/Apache2.2/htdocs"
ErrorLog :: "C:/Program Files/Apache Software Foundation/Apache2.2/logs/error.log"
AccessLog :: "C:/Program Files/Apache Software Foundation/Apache2.2/logs/access.log"
cgi-bin :: "C:/Program Files/Apache Software Foundation/Apache2.2/cgi-bin/"
binaries (apachectl) :: "C:/Program Files/Apache Software Foundation/Apache2.2/bin"
Solaris 10 (Apache httpd 2.0):
ServerRoot :: /usr/apache2
Config File :: /etc/apache2/httpd.conf
DocumentRoot :: /var/apache2/htdocs
ErrorLog :: /var/apache2/logs/error_log
AccessLog :: /var/apache2/logs/access_log
cgi-bin :: /var/apache2/cgi-bin
binaries :: /usr/apache2/bin
Slackware 12.0+ (Apache httpd 2.2):
ServerRoot :: /usr
DocumentRoot :: /svr/httpd/htdocs
AccessLog :: /var/log/httpd/access_log
ErrorLog :: /var/log/httpd/error_log
binaries (apachectl) :: /usr/sbin
modules :: /usr/lib/httpd
system startup script :: /etc/rc.d/rc.httpd (start|restart|graceful|graceful-stop|stop)
Apache config file :: /etc/httpd/httpd.conf
mod_ssl config file :: /etc/httpd/extra/httpd-ssl.conf
php config file :: /etc/httpd/mod_php.conf
cgi-bin :: /svr/httpd/cgi-bin
on-line docs ("manual") :: /svr/httpd/htdocs/manual
openSUSE and SLES (Apache httpd 2.2):
ServerRoot :: /srv/www
DocumentRoot :: /srv/www/htdocs
Apache Config File :: /etc/apache2/httpd.conf
Other Config Files :: /etc/sysconfig/apache2
SSL Config File :: /etc/apache2/ssl-global.conf
ErrorLog :: /var/log/apache2/error_log
AccessLog :: /var/log/apache2/access_log
cgi-bin :: /srv/www/cgi-bin
binaries (apachectl) :: /usr/sbin
start/stop :: /etc/init.d/apache2 (start|restart|restart-graceful|reload|graceful|graceful-stop|stop|configtest)
Gentoo (Apache httpd 2.2):
ServerRoot :: /usr/lib/apache2
DocumentRoot :: /var/www/localhost/htdocs
Apache Config File :: /etc/apache2/httpd.conf
Other Config Files :: /etc/conf.d/apache2
Default VHost Config :: /etc/apache2/vhosts.d/00_default_vhost.conf
Module Configuration :: /etc/apache2/modules.d
Module Locations :: /usr/lib/apache2/modules
ErrorLog :: /var/log/apache2/error_log
AccessLog :: /var/log/apache2/access_log
cgi-bin :: /var/www/localhost/cgi-bin
binaries (apache2ctl) :: /usr/sbin
start/stop :: /etc/init.d/apache2 (start|restart|graceful|stop|configtest)
Taken from http://wiki.apache.org/httpd/DistrosDefaultLayout