Apache HTTP Server – Command Reference Table (with Examples)

1. Service Management (Start/Stop/Restart)

Command	Description	Example	Output/Usage
systemctl start httpd	Starts the Apache service	sudo systemctl start httpd	Starts Apache web server
systemctl stop httpd	Stops the Apache service	sudo systemctl stop httpd	Shuts down Apache
systemctl restart httpd	Restarts Apache service	sudo systemctl restart httpd	Applies config changes
systemctl reload httpd	Reloads Apache config without downtime	sudo systemctl reload httpd	Graceful reload
systemctl status httpd	Shows status of Apache	sudo systemctl status httpd	Running/Failed info
systemctl enable httpd	Enable Apache to start on boot	sudo systemctl enable httpd	Auto-start at boot
systemctl disable httpd	Disable Apache at boot	sudo systemctl disable httpd	Stop auto-start
apachectl graceful	Gracefully restarts Apache	sudo apachectl graceful	No connection drop
apachectl restart	Restart Apache	sudo apachectl restart	Full restart
apachectl stop	Stop Apache	sudo apachectl stop	Hard stop

Command Name	Description	Example
systemctl start apache2	Starts the Apache service on Debian/Ubuntu (Systemd).	sudo systemctl start apache2
systemctl start httpd	Starts the Apache service on CentOS/RHEL (Systemd).	sudo systemctl start httpd
service apache2 start	Starts the Apache service on Debian/Ubuntu (SysVinit).	sudo service apache2 start
service httpd start	Starts the Apache service on CentOS/RHEL (SysVinit).	sudo service httpd start
systemctl enable apache2	Enables Apache to start automatically at boot on Debian/Ubuntu (Systemd).	sudo systemctl enable apache2
systemctl enable httpd	Enables Apache to start automatically at boot on CentOS/RHEL (Systemd).	sudo systemctl enable httpd
chkconfig apache2 on	Enables Apache to start at boot on Debian/Ubuntu (SysVinit).	sudo chkconfig apache2 on
chkconfig httpd on	Enables Apache to start at boot on CentOS/RHEL (SysVinit).	sudo chkconfig httpd on
systemctl stop apache2	Stops the Apache service on Debian/Ubuntu (Systemd).	sudo systemctl stop apache2
systemctl stop httpd	Stops the Apache service on CentOS/RHEL (Systemd).	sudo systemctl stop httpd
service apache2 stop	Stops the Apache service on Debian/Ubuntu (SysVinit).	sudo service apache2 stop
service httpd stop	Stops the Apache service on CentOS/RHEL (SysVinit).	sudo service httpd stop
systemctl restart apache2	Restarts the Apache service (stops and starts) on Debian/Ubuntu (Systemd).	sudo systemctl restart apache2
systemctl restart httpd	Restarts the Apache service on CentOS/RHEL (Systemd).	sudo systemctl restart httpd
service apache2 restart	Restarts the Apache service on Debian/Ubuntu (SysVinit).	sudo service apache2 restart
service httpd restart	Restarts the Apache service on CentOS/RHEL (SysVinit).	sudo service httpd restart
systemctl reload apache2	Reloads Apache configuration without stopping the service (graceful restart) on Debian/Ubuntu.	sudo systemctl reload apache2
systemctl reload httpd	Reloads Apache configuration on CentOS/RHEL.	sudo systemctl reload httpd
service apache2 reload	Reloads Apache configuration on Debian/Ubuntu (SysVinit).	sudo service apache2 reload
service httpd reload	Reloads Apache configuration on CentOS/RHEL (SysVinit).	sudo service httpd reload
systemctl status apache2	Checks the status of the Apache service on Debian/Ubuntu (Systemd).	sudo systemctl status apache2
systemctl status httpd	Checks the status of the Apache service on CentOS/RHEL (Systemd).	sudo systemctl status httpd
service apache2 status	Checks the status of the Apache service on Debian/Ubuntu (SysVinit).	sudo service apache2 status
service httpd status	Checks the status of the Apache service on CentOS/RHEL (SysVinit).	sudo service httpd status

---

2. Configuration Checking

Command	Description	Example	Output/Usage
apachectl configtest	Test Apache config syntax	sudo apachectl configtest	Shows Syntax OK or errors
httpd -t	Another way to test config	sudo httpd -t	Syntax validation
httpd -S	Show vhost configuration	sudo httpd -S	VHost layout and issues
apachectl -t -D DUMP_VHOSTS	List all virtual hosts	sudo apachectl -t -D DUMP_VHOSTS	Host/port mapping
apachectl -t -D DUMP_MODULES	List all loaded modules	sudo apachectl -t -D DUMP_MODULES	Active modules
apachectl -t -D DUMP_RUN_CFG	Show running config	sudo apachectl -t -D DUMP_RUN_CFG	Runtime configuration

Command Name	Description	Example
httpd -d <serverroot>	Sets the ServerRoot directory for configuration files.	httpd -d /usr/local/apache2
httpd -f <config>	Specifies a custom configuration file.	httpd -f /etc/httpd/conf/custom.conf
httpd -C <directive>	Processes a directive before reading config files.	httpd -C "Include /etc/httpd/extra.conf"
httpd -c <directive>	Processes a directive after reading config files.	httpd -c "LogLevel debug"
httpd -D <parameter>	Sets a parameter for use with <IfDefine> directives.	httpd -D SSL
httpd -e <level>	Sets LogLevel during startup for debugging.	httpd -e debug
httpd -E <file>	Sends startup error messages to a file.	httpd -E /var/log/httpd/startup_errors.log
httpd -k start	Starts the Apache server.	httpd -k start
httpd -k restart	Restarts the Apache server.	httpd -k restart
httpd -k graceful	Gracefully restarts Apache without closing connections.	httpd -k graceful
httpd -k stop	Stops the Apache server.	httpd -k stop
httpd -k graceful-stop	Gracefully stops Apache without closing connections.	httpd -k graceful-stop
httpd -h	Displays a summary of command-line options.	httpd -h
httpd -l	Lists modules compiled into the server.	httpd -l
httpd -L	Lists all directives with their arguments and valid locations.	httpd -L
httpd -S	Shows parsed virtual host settings from the configuration file.	httpd -S
httpd -t	Tests configuration files for syntax errors.	httpd -t
httpd -T	Tests configuration files without checking document roots.	httpd -T
httpd -v	Prints the Apache version and exits.	httpd -v
httpd -V	Prints the Apache version and build parameters, then exits.	httpd -V
httpd -X	Runs Apache in single-process debug mode (no forking).	httpd -X
httpd -M	Lists all loaded modules (static and dynamic).	httpd -M

---

3. Apache Files and Paths (Default)

File/Path	Description	Example
/etc/httpd/conf/httpd.conf	Main Apache config file	Configure ports, modules, logging
/etc/httpd/conf.d/	Directory for custom .conf files	Add vhosts here
/var/www/html/	Default document root	Store website files here
/etc/httpd/logs/ or /var/log/httpd/	Log directory	Access and error logs

Command Name	Description	Example
apachectl start	Starts the Apache HTTP daemon. Errors if already running.	sudo apachectl start
apachectl stop	Stops the Apache HTTP daemon.	sudo apachectl stop
apachectl restart	Restarts the Apache daemon (stops and starts, checks configuration).	sudo apachectl restart
apachectl graceful	Gracefully restarts Apache without aborting open connections.	sudo apachectl graceful
apachectl graceful-stop	Gracefully stops Apache without aborting open connections.	sudo apachectl graceful-stop
apachectl configtest	Tests configuration files for syntax errors without starting the server.	sudo apachectl configtest
apachectl status	Displays a full status report using mod_status (requires text-based browser like lynx).	sudo apachectl status
apachectl fullstatus	Similar to status, provides detailed server status (requires mod_status).	sudo apachectl fullstatus

---

4. Manual Testing Commands

Command	Description	Example	Use
curl http://localhost	Test if Apache is serving pages	curl http://localhost	Get default page
`netstat -tulnp	grep :80`	Check if port 80 is open	`sudo netstat -tulnp
`ss -tuln	grep :80`	Alternative to netstat	`sudo ss -tuln
`ps aux	grep httpd`	Check running Apache processes	`ps aux

---

5. Installation Commands

Command	Description	Example
yum install httpd	Install Apache (CentOS/RHEL)	sudo yum install httpd -y
apt install apache2	Install Apache (Debian/Ubuntu)	sudo apt install apache2 -y
dnf install httpd	Fedora/RHEL 8+ installation	sudo dnf install httpd -y

---

6. Log Management

Log File	Description	Example
/var/log/httpd/access_log	Tracks all access requests	sudo tail -f /var/log/httpd/access_log
/var/log/httpd/error_log	Logs errors	sudo tail -f /var/log/httpd/error_log
journalctl -u httpd	View Apache logs via systemd	sudo journalctl -u httpd

---

7. Module Management

Command	Description	Example
a2enmod <module>	Enable module (Debian/Ubuntu)	sudo a2enmod rewrite
a2dismod <module>	Disable module	sudo a2dismod autoindex
apachectl -M	Show loaded modules	sudo apachectl -M

Command Name	Description	Example
a2enmod <module>	Enables a specific Apache module by creating a symlink in mods-enabled.	sudo a2enmod rewrite
a2dismod <module>	Disables a specific Apache module by removing the symlink from mods-enabled.	sudo a2dismod proxy_http2

---

8. Virtual Host Configuration (Sample Format)

<VirtualHost *:80>
    ServerName www.example.com
    DocumentRoot /var/www/example
    ErrorLog /var/log/httpd/example_error.log
    CustomLog /var/log/httpd/example_access.log combined
</VirtualHost>

Enable with:

sudo systemctl reload httpd

---

9. Reload Without Downtime

Command	Description	Example
apachectl graceful	Reload config without killing connections	sudo apachectl graceful

---

Summary Table: Most Used Apache Commands

Purpose	Command	Example
Start Apache	systemctl start httpd	sudo systemctl start httpd
Test Config	apachectl configtest	sudo apachectl configtest
Restart Apache	apachectl restart	sudo apachectl restart
Check Virtual Hosts	apachectl -S	sudo apachectl -S
View Logs	journalctl -u httpd	sudo journalctl -u httpd
Enable Auto-start	systemctl enable httpd	sudo systemctl enable httpd
Install Apache	apt install apache2	sudo apt install apache2
Check Modules	apachectl -M	sudo apachectl -M

---