In a CentOS 7 environment, configuring logging for Apache or Nginx web servers can be crucial for server management and security. Log separation by virtual hosts allows for better organization and facilitates analysis of access or site-specific issues. This article provides concrete steps on how to configure logging for Apache and Nginx with this goal in mind.

Apache

1. Installation and Basic Configuration

   • Ensure you have Apache web server installed (httpd in CentOS). You can install it using yum install httpd.

2. Virtual Host Configuration

   • To separate logs, you first need to configure virtual hosts. Configuration files for virtual hosts are typically located in /etc/httpd/conf.d/.
   • Create a new configuration file for each virtual host, e.g., mysite.conf, and configure virtual hosts as needed.

3. Logging Configuration

   • Within each <VirtualHost> directive, add commands to specify the path and name of log files. For example:

     ErrorLog /var/log/httpd/mysite_error.log
     CustomLog /var/log/httpd/mysite_access.log combined
     ​

   • This way, you can define separate log files for errors and accesses for each virtual host.

4. Restart Apache

   • To apply the new configuration, restart the Apache server using systemctl restart httpd.

4. Restart Apache

   • To apply the new configuration, restart the Apache server using systemctl restart httpd.

Nginx

1. Installation and Basic Configuration

   • Ensure you have Nginx installed. If not, install it using yum install nginx.

2. Virtual Host Configuration

   • For Nginx, virtual host (server blocks) configuration is done in files within the /etc/nginx/conf.d/ directory.
   • Create a configuration file for each virtual host, e.g., mysite.conf.

3. Logging Configuration

   • Within each server block, specify paths to access and error log files. For example:

     access_log /var/log/nginx/mysite_access.log;
     error_log /var/log/nginx/mysite_error.log;
     ​

   • This ensures that each virtual host has its own logs.

4. Restart Nginx

   • To apply the changes, restart Nginx using systemctl restart nginx.

Conclusion: Log separation by virtual hosts is an effective strategy for organizing and analyzing logging data from your web servers. Follow the above steps to configure Apache or Nginx on CentOS 7, enabling better control over logging and simplifying server management.