Table of Contents
Introduction to Apache Web Server
In this guide let us see how to install Apache Web Server in RHEL 7, Centos 7, Oracle Linux 7. By following we are going to cover most of all Apache-related topics. We are about to use Apache 2.4 version in this guide.
Below articles are related to Apache topic.
Installing Packages
To install the Apache server we need to install with httpd package.
# yum install httpd -y
Transaction test succeeded
Running transaction
Installing : httpd-2.4.6-45.el7.x86_64
Verifying : httpd-2.4.6-45.el7.x86_64
Installed:
httpd.x86_64 0:2.4.6-45.el7
Complete!
[root@rhel ~]#
Once done with installation we can verify using yum or rpm query.
# yum list installed | grep httpd # rpm -qa | grep httpd
Apache Configuration file location
By default, the apache configuration file will be underlying under below location.
# ls -lthr /etc/httpd/conf/httpd.conf
[root@rhel ~]# ls -lthr /etc/httpd/conf/httpd.conf -rw-r--r--. 1 root root 12K Aug 3 2016 /etc/httpd/conf/httpd.conf [root@rhel ~]#
Knowing default welcome page config location
Once we start the apache service we will get a welcome page in the browser while navigating to Apache server using IP or localhost, that information is coming from below file welcome.conf.
File userdir.conf which used to define user home directory as default webroot document for a user.
# ls -lthr /etc/httpd/conf.d/
[root@rhel ~]# ls -lthr /etc/httpd/conf.d/ total 16K -rw-r--r--. 1 root root 516 Aug 3 2016 welcome.conf -rw-r--r--. 1 root root 1.3K Aug 3 2016 userdir.conf -rw-r--r--. 1 root root 2.9K Aug 3 2016 autoindex.conf -rw-r--r--. 1 root root 366 Aug 3 2016 README [root@rhel ~]#
Location of Apache modules configs
These modules are imported into Apache configuration by using .conf files it will be defined by the following directive.
Include conf.modules.d/*.conf
[root@rhel ~]# ls -lthr /etc/httpd/conf.modules.d/ total 28K -rw-r--r--. 1 root root 451 Aug 3 2016 01-cgi.conf -rw-r--r--. 1 root root 88 Aug 3 2016 00-systemd.conf -rw-r--r--. 1 root root 957 Aug 3 2016 00-proxy.conf -rw-r--r--. 1 root root 742 Aug 3 2016 00-mpm.conf -rw-r--r--. 1 root root 41 Aug 3 2016 00-lua.conf -rw-r--r--. 1 root root 139 Aug 3 2016 00-dav.conf -rw-r--r--. 1 root root 3.7K Aug 3 2016 00-base.conf [root@rhel ~]#
To list more modules we can locate it under /etc/httpd/modules/ this location soft linked to /usr/lib64/httpd/modules.
# ls -lthr /etc/httpd/modules/
Output truncated due to long listed output.
[root@rhel ~]# ls -lthr /etc/httpd/modules/ total 2.5M -rwxr-xr-x. 1 root root 20K Aug 3 2016 mod_watchdog.so -rwxr-xr-x. 1 root root 15K Aug 3 2016 mod_vhost_alias.so -rwxr-xr-x. 1 root root 11K Aug 3 2016 mod_version.so -rwxr-xr-x. 1 root root 15K Aug 3 2016 mod_usertrack.so -rwxr-xr-x. 1 root root 11K Aug 3 2016 mod_userdir.so -rwxr-xr-x. 1 root root 15K Aug 3 2016 mod_unixd.so -rwxr-xr-x. 1 root root 11K Aug 3 2016 mod_unique_id.so
Location of log files
Under Apache configuration file it will be defined as follows, It will be logged with only warnings, we can change the logging mode as per our requirement.
ErrorLog "logs/error_log" LogLevel warn CustomLog "logs/access_log" combined
Location as follows
# ls -lthr /var/log/httpd/
[root@rhel ~]# ls -lthr /var/log/httpd/ total 8.0K -rw-r--r--. 1 root root 2.4K Nov 24 09:48 error_log -rw-r--r--. 1 root root 2.2K Nov 24 09:48 access_log [root@rhel ~]#
Knowing PID file location of Apache
PID file of Apache service will be under /var/run/httpd/ in case we need to clear PID file below is the location where we need to look for PID files.
# ls -lthr /var/run/httpd/
[root@rhel ~]# ls -lthr /var/run/httpd/ total 8.0K drwx------. 2 apache apache 40 Aug 3 2016 htcacheclean -rw-r--r--. 1 root root 8 Nov 24 10:15 authdigest_shm.2708 -rw-r--r--. 1 root root 5 Nov 24 10:15 httpd.pid [root@rhel ~]#
Apache default important directives
Below are few of default directives which we need to know in Apache web server, these directives will be covered in next upcoming guides.
# egrep -w --color '^Listen|^ServerRoot|^ServerAdmin|^User|^Group|^Include' /etc/httpd/conf/httpd.conf
[root@rhel ~]# egrep -w --color '^Listen|^ServerRoot|^ServerAdmin|^User|^Group|^Include' /etc/httpd/conf/httpd.conf ServerRoot "/etc/httpd" Listen 80 Include conf.modules.d/*.conf User apache Group apache ServerAdmin root@localhost [root@rhel ~]#
Managing Apache service
To start, stop, restart we can use two methods.
To start the Apache service we can use two methods.
# apachectl start # apachectl restart # apachectl stop # systemctl start httpd # systemctl restart httpd # systemctl stop httpd
To make any changes without restarting service and it should allow the existing apache request we can use graceful option by following apachectl.
# apachectl graceful
To make the service persistent during reboot
# systemctl enable httpd
Firewall rules for Apache
If the server enabled with firewalld service we need to allow the HTTP and HTTPS traffic as shown below.
# firewall-cmd --add-service=http --permanent # firewall-cmd --add-service=https --permanent # firewall-cmd --list-all
[root@rhel /]# firewall-cmd --add-service=http --permanent success [root@rhel /]# firewall-cmd --add-service=https --permanent success [root@rhel /]# firewall-cmd --list-all public (active) target: default icmp-block-inversion: no interfaces: ens33 sources: services: dhcpv6-client http https ssh ports: 514/tcp protocols: masquerade: no forward-ports: sourceports: icmp-blocks: rich rules: [root@rhel /]#
That’s it, for installing and looking into Apache configuration, By following we are about to see most of the apache configurations and setups.
Conclusion
Apache web server is one of the very popular web servers for a long time, most of the well known popular websites are hosted on Apache webserver. Hope above guide through important configurations files and steps to configure the apache helps you. Subscribe to our newsletter and stay connected.