[root@myweb root]# grep -r "xxxtech" /etc
/etc/httpd/conf/httpd.conf: ServerName www.xxxtech.com
[root@myweb root]# grep -rnw '/etc' -e 'xxxtech'
[root@myweb root]# grep -rnw '/etc' -e 'xxxtech'
/etc/httpd/conf/httpd.conf:383: ServerName www.xxxtech.com
[root@myweb root]# grep -Ril "xxxtech" /etc
[root@myweb root]# grep -Ril "xxxtech" /etc
/etc/httpd/conf/httpd.conf
/etc/httpd/logs/access_log-20190922
/etc/httpd/logs/access_log-20190929
/etc/httpd/logs/access_log-20191006
/etc/httpd/logs/access_log-20191013
/etc/httpd/logs/access_log
/etc/httpd/logs/error_log
[root@myweb root]# find /etc -type f -exec grep -H 'xxxtech' {} \;
[root@myweb root]# find /etc -type f -exec grep -H 'xxxtech' {} \;
/etc/httpd/conf/httpd.conf: ServerName www.xxxtech.com
[root@myweb root]# find /etc -name '*.conf' -exec grep -i 'xxxtech' {} \; -print
[root@myweb root]# find /etc -name '*.conf' -exec grep -i 'xxxtech' {} \; -print
ServerName www.xxxtech.com
/etc/httpd/conf/httpd.conf
Install
Apache
Before
we begin with the mod_rewrite module setup, we need to install the Apache web server.
To install Apache, run
the following command:
sudo yum install httpd -y
After installing Apache,
start the httpd service and enable it to start automatically on boot.
We can do this using the
following commands:
sudo systemctl start httpd.service
sudo systemctl enable httpd.service
Next, we should allow
access to the default Apache port 80 (HTTP) using firewalld.
We can do this by running
the following command:
sudo firewall-cmd --permanent --add-port=80/tcp
Now, reload the firewall
service for the changes to take effect.
sudo systemctl restart firewalld.service
Enable
Mod_rewrite Module
The mod_rewrite module
is enabled by default on CentOS 7. If you find it is not enabled on your
server, you can enable it by editing 00-base.conf file located
in /etc/httpd/conf.modules.d/ directory.
sudo nano /etc/httpd/conf.modules.d/00-base.conf
Add or uncomment the
following line:
LoadModule rewrite_module modules/mod_rewrite.so
Save and close the file,
then restart the httpd service:
sudo systemctl restart httpd
Enable
.Htaccess File
Once
the mod_rewrite module
has been activated, you can set up your URL rewrites by creating an .htaccess file
in your default document root directory. A .htaccess file allows us to
modify our rewrite rules without accessing server configuration files. For this
reason, .htaccess is critical to your web server. Before we begin, we need
to allow Apache to read .htaccess files located under
the /var/www/html directory.
You can do this by
editing httpd.conf file:
sudo nano /etc/httpd/conf/httpd.conf
Find the section <directory
/var/www/html> and change AllowOverride None to AllowOverride
All
<Directory
/var/www/html>
AllowOverride All
</Directory>
Save and exit.
Now restart Apache to put
the change into effect:
sudo systemctl restart httpd
Configure
Rewrite Module
In this
section, we will explain basic mod_rewrite syntax and give some examples.
You can write
RewriteRules using the following format:
RewriteRule pattern substitution [flags]
- RewriteRule: This directive specifies the name of the the mod_rewrite directive that you want to use.
- Pattern: This directive specifies a regular expression that matches the desired string
- Substitution: This directive specifies the path of the actual URL of the page with the information you want to display.
- Flags: A flag is a tag at the end of the Rewrite Rule directive that specifies optional parameters that can modify the rule.
Let's discuss
RewriteRules with some examples:
Redirect
Www To Non-Www
If you want to redirect
users from www to a plain non-www domain, you will
need to create .htaccess file in Apache document root directory.
Change directories to
your Document root:
cd /var/www/html
Create the .htaccess file:
sudo nano .htaccess
Add the following
content:
RewriteEngine On
RewriteBase /
RewriteCond %{HTTP_HOST} ^www\.(.*)$ [NC]
RewriteRule ^(.*)$ http://%1/$1 [R=301,L]
Save and exit the file.
We can use curl to
test that the www domain redirects to the non-www domain:
curl -I http://www.yourdomain.com
You should see the
following output:
HTTP/1.1 301 Moved Permanently
Date: Mon, 03 May 2016 18:20:53 GMT
Server: Apache/2.4.6 (CentOS)
Location: http://yourdomain.com/
Content-Type: text/html; charset=iso-8859-1
Above output shows the
non-www redirect location http://yourdomain.com/
Redirect
Non-Www To Www
If you want to redirect
users from a plain non-www domain to a www domain, add the
following content to your .htaccess file:
sudo nano /var/www/html/.htaccess
Add the following
content:
RewriteEngine On
RewriteBase /
RewriteCond %{HTTP_HOST} !^www\. [NC]
RewriteRule ^(.*)$ http://www.%{HTTP_HOST}/$1 [R=301,L]
Save and exit the file.
Now, use curl command
to ensure that the non-www domain redirects to the www domain:
curl -I http://yourdomain.com
You should see the
following output:
HTTP/1.1 301 Moved Permanently
Date: Mon, 03 May 2016 18:20:53 GMT
Server: Apache/2.4.6 (CentOS)
Location: http://www.yourdomain.com/
Content-Type: text/html; charset=iso-8859-1
Above output shows
the www redirect
location http://www.yourdomain.com/
Redirect
All Website Pages
If you want to redirect
all pages from "olddomain.com" to "newdomain.com", edit
the .htaccess file:
sudo nano /var/www/html/.htaccess
Add the following
content:
Options +FollowSymLinks
RewriteEngine on
RewriteCond %{HTTP_HOST} ^www.olddomain.com$ [OR]
RewriteCond %{HTTP_HOST} ^olddomain.com$
RewriteRule ^(.*)$ http://www.newdomain.com/$1 [R=301,L]
Save and exit the file.
Now, use curl to
test that the "www.olddomain.com" domain redirects to the
"www.newdomain.com" domain:
curl -I http://www.olddomain.com
You should get a 301
Moved Permanently response that shows you the new domain redirect
location.
Deny
File Type Access
If you want to deny users
to access specific file types such as: .pdf, .css, .gif, .png,
or .bmp then
edit your .htacces file:
sudo nano /var/www/html/.htaccess
Add the following
content:
RewriteEngine on
RewriteRule .*\.(pdf|css|gif|png|bmp)$ - [F,NC]
Save and exit the file.
