常見的 Apache 模塊有：

1. mod_ssl– 提供了 HTTPS 功能。
2. mod_rewrite– 可以用正則表達式匹配 url 樣式，並且使用.htaccess技巧來進行透明轉發，或者提供 HTTP 狀態碼回應。
3. mod_security– 用於保護 Apache 免於暴力破解或者 DDoS 攻擊。
4. mod_status - 用於監測 Apache 的負載及頁面統計。

在 Linux 中apachectl 或者 apache2ctl用於控制 Apache 服務器，是 Apache 的前端。

你可以用下面的命令顯示 apache2ctl 的使用信息：

$ apache2ctl help或者$ apachectl help

Usage: /usr/sbin/httpd [-D name] [-d directory] [-f file]                       [-C "directive"] [-c "directive"]                       [-k start|restart|graceful|graceful-stop|stop]                       [-v] [-V] [-h] [-l] [-L] [-t] [-S]Options:  -D name            : define a name for use in  directives  -d directory       : specify an alternate initial ServerRoot  -f file            : specify an alternate ServerConfigFile  -C "directive"     : process directive before reading config files  -c "directive"     : process directive after reading config files  -e level           : show startup errors of level (see LogLevel)  -E file            : log startup errors to file  -v                 : show version number  -V                 : show compile settings  -h                 : list available command line options (this page)  -l                 : list compiled in modules  -L                 : list available configuration directives  -t -D DUMP_VHOSTS  : show parsed settings (currently only vhost settings)  -S                 : a synonym for -t -D DUMP_VHOSTS  -t -D DUMP_MODULES : show all loaded modules   -M                 : a synonym for -t -D DUMP_MODULES  -t                 : run syntax check for config files

apache2ctl 可以工作在兩種模式下，SysV init 模式和直通模式。在 SysV init 模式下，apache2ctl用如下的簡單的單命令形式：

$ apachectl command或者$ apache2ctl command

比如要啟動並檢查它的狀態，運行這兩個命令。如果你是普通用戶，使用 sudo 命令來以 root 用戶權限來運行：

$ sudo apache2ctl start$ sudo apache2ctl status

tecmint@TecMint ~ $ sudo apache2ctl startAH00558: apache2: Could not reliably determine the server's fully qualified domain name, using 127.0.1.1/. Set the 'ServerName' directive globally to suppress this messagehttpd (pid 1456) already runningtecmint@TecMint ~ $ sudo apache2ctl statusApache Server Status for localhost (via 127.0.0.1)Server Version: Apache/2.4.18 (Ubuntu)Server MPM: preforkServer Built: 2016-07-14T12:32:26-------------------------------------------------------------------------------Current Time: Tuesday, 15-Nov-2016 11:47:28 ISTRestart Time: Tuesday, 15-Nov-2016 10:21:46 ISTParent Server Config. Generation: 2Parent Server MPM Generation: 1Server uptime: 1 hour 25 minutes 41 secondsServer load: 0.97 0.94 0.77Total accesses: 2 - Total Traffic: 3 kBCPU Usage: u0 s0 cu0 cs0.000389 requests/sec - 0 B/second - 1536 B/request1 requests currently being processed, 4 idle workers__W__.................................................................................................................................................Scoreboard Key:"_" Waiting for Connection, "S" Starting up, "R" Reading Request,"W" Sending Reply, "K" Keepalive (read), "D" DNS Lookup,"C" Closing connection, "L" Logging, "G" Gracefully finishing,"I" Idle cleanup of worker, "." Open slot with no current process

當在直通模式下，apache2ctl可以用下面的語法帶上所有 Apache 的參數：

$ apachectl [apache-argument]$ apache2ctl [apache-argument]

可以用下面的命令列出所有的 Apache 參數：

$ apache2 help    [在基於Debian的系統中]$ httpd help      [在RHEL的系統中]

-t -D DUMP_MODULES

---------------  在基於 Debian 的系統中 --------------- $ apache2ctl -t -D DUMP_MODULES   或者 $ apache2ctl -M

---------------  在 RHEL 的系統中 --------------- $ apachectl -t -D DUMP_MODULES   或者 $ httpd -M$ apache2ctl -M

[root@tecmint httpd]# apachectl -MLoaded Modules: core_module (static) mpm_prefork_module (static) http_module (static) so_module (static) auth_basic_module (shared) auth_digest_module (shared) authn_file_module (shared) authn_alias_module (shared) authn_anon_module (shared) authn_dbm_module (shared) authn_default_module (shared) authz_host_module (shared) authz_user_module (shared) authz_owner_module (shared) authz_groupfile_module (shared) authz_dbm_module (shared) authz_default_module (shared) ldap_module (shared) authnz_ldap_module (shared) include_module (shared)....