Book Image

Ubuntu Server Cookbook

By : Uday Sawant
Book Image

Ubuntu Server Cookbook

By: Uday Sawant

Overview of this book

Ubuntu is one of the most secure operating systems and defines the highest level of security as compared other operating system. Ubuntu server is a popular Linux distribution and the first choice when deploying a Linux server. It can be used with a $35 Raspberry Pi to top-notch, thousand-dollar-per-month cloud hardware. Built with lists that there are 4 million + websites built using Ubuntu. With its easy-to-use package management tools and availability of well-known packages, we can quickly set up our own services such as web servers and database servers using Ubuntu. This book will help you develop the skills required to set up high performance and secure services with open source tools. Starting from user management and an in-depth look at networking, we then move on to cover the installation and management of web servers and database servers, as well as load balancing various services. You will quickly learn to set up your own cloud and minimize costs and efforts with application containers. Next, you will get to grips with setting up a secure real-time communication system. Finally, we’ll explore source code hosting and various collaboration tools. By the end of this book, you will be able to make the most of Ubuntu’s advanced functionalities.
Table of Contents (20 chapters)
Ubuntu Server Cookbook
Credits
About the Author
www.PacktPub.com
Preface
Index

Troubleshooting the mail server


Sometimes you may face problems such as e-mails not being sent, delayed delivery or mail bouncing, issues while fetching e-mails, and login failures. In this recipe, we will learn how to identify the exact problem behind these issues. We will learn how to use debugging tools and read the logs of Postfix and Dovecot.

Getting ready

You will need access to a root account or an account with sudo privileges.

It is assumed that you have already installed Postfix and Dovecot servers.

How to do it…

Follow these steps to troubleshoot the mail server:

  1. Start with checking the status of Postfix and Dovecot. If you get output that says stop/waiting or not running then the respective service is not running:

    $ sudo service postfix status
    $ sudo service dovecot status
    
  2. Try to restart the respective services. Restarting may give you error messages. Also check for startup logs under /var/log/mail.log:

    $ sudo service postfix restart
    $ less /var/log/mail.log
    
  3. You can use a tail command...