RdCpXbroAk' alt='Install Roundcube On Ubuntu Server Tutorial' title='Install Roundcube On Ubuntu Server Tutorial' />To install iRedMail on Debian or Ubuntu Linux, you need A FRESH, working DebianUbuntu Linux.Supported releases are listed on Download page.Setup a mail server with Postfix and Dovecot on Ubuntu Debian.Mail system for your own domain.You have your own domain name and your very own vpsdedicated server and want to use the domain name for emails.So you need to setup a mail server using an smtp server and an imappop server.This tutorial shows you how to setup Postfix smtp server and Dovecot imappop server.The task of the smtp server is to accept incoming mails and relay outgoing mails from authorised users on the system.Whereas Dovecot allows authorized users to access their Inbox and read whatever mails there are.The Simple Configuration We are not doing this.In the simplest kind of configuration for Postfix, just specify your domain name xyz.This technique is simple but with heavy drawbacks.Firstly you need to create a new unix user account for every new email address we need.Secondly the users have to login with their system passwords.So this is not a very flexible strategy to setup mail accounts.Separately you can configure Dovecot to read the incoming mails from the directory where Postfix stores them varmail by default.There is an article on Digital.Ocean that shows how to setup postfix with dovecot like that.We are going to setup things in a way that you can quickly create email addresses just by writing them in a file along with the password.We shall add as many domains as we like and create as many emails and it would all be encrypted and authenticated.Since the email accounts we shall be creating are not related to any system users or system domains, they are called virtual users and virtual domains.Virtual means, that not related to any system specific thing.How will it work The technical jargon.All incoming mails destined to your server shall be received by Postfix SMTP and then handed over to Dovecot LMTP for storing in the Inbox.This is better because dovecots inbuilt lmtp service offers more features like quotas, permissions, flexible directory structures for mailboxes etc.Incoming mail From somewhere Postfix SMTP Dovecot LMTP Mail.BoxInbox. And due to this Postfix is reduced to just a tranmission agent that just moves mails in and out, and nothing else.All outgoing mails shall be send out by Postfix.But only from authenticated accounts.Outgoing mail Thunderbird Postfix SMTP Destination SMTP like gmail.Dovecot shall provide IMAPPOP services to allow mail clients to read Inbox.Thunderbird lt Dovecot IMAP lt Inbox.You can turn on or off firewall on windows server 2012, using powershell command.There is allways the gui way.Do not stop firewall service.You will loose your.Overview. Why build your own mail server instead of outsourcing to external entities Major open source softwares used in iRedMail, and big picture of mail flow.Debian Wheezy Mail Server Postfix Dovecot Sasl MySQL PostfixAdmin RoundCube SpamAssassin Clamav Greylist Nginx PHP5.Dovecot shall exclusively provide authentication mechanism to Postfix via SASL.The email accounts username passwords shall be stored in a file.If you wish to setup domains and email accounts in a database instead of a file, then following this tutorial at linode.Roundcube-Webmail-Inbox-.png' alt='Install Roundcube On Ubuntu Server Tutorial' title='Install Roundcube On Ubuntu Server Tutorial' />Setup MX records for domain.Before getting any further, ensure that the MX records for your domains that you are going to use with your mail server, are properly set.Most server providers like Linode provide an easy interface to setup zone entries for mx records.If your domain is example.Use the dig command to verify Find the MX mail exchange server.MX amazon. com short.Find the ip address of the mx server.Ensure that the ip address of your MX mail server is of that server on which you are going to setup postfix and dovecot.Install and Configure Postfix.The first thing to setup is Postfix.Do not forget that in our setup, Postfix is going to transmit all outgoing mails, but for all incoming mails, it would hand them over to Dovecot for storage and later access by email clients.Things to know first.Postfix logs all its actions in a file called varlogmail.Check it for useful information and save time diagnosing problems.The postconf command is the tool to peek inside the configurations of Postfix.It lists out everything in a namevalue format linewise.So use the grep command to find whatever needed.All the Postfix configuration parameters lie in the file etcpostfixmain.The parameters are explained in man pages found at man 5 postconfInstall Postfix.Okay, so if you havent already done so, install Postfix.Its right there in the repositories so you shouldnt look elsewhere unless you want something newer.Dont worry, the rest is not going to be that easy.After installing Postfix you may want to check the version.Here is the command to do that.Configure main. cf.In this section we shall configure several things in the Postfix main configuration file located at etcpostfixmain.These include hostnames, parameters for SASL authentication, unix sockets for dovecot lmtp and dovecot sasl authentication service and list of our virtualmailboxdomains for which Postfix shall be responsible for receiving incoming mails.The tricky parameters The following parameters are the 3 super confusing parameters that you need to understand and configure properly to avoid unexpected problems.You could be hosting multiple domains on your server, say abc.You have to use one of them as a primary domain and use it for myorigin.The myorigin field is the one that is configured automatically while postfix installs and asks you for the domain of the server.By default myorigin is configured to point to etcmailname so you can either fill in your default domain in etcmailname or specify in the configuration file directly.The domain specified with myorigin is used for mails generated by Postfix.For example when it fails to deliver a mail, it would reply with a from address of Mail Delivery Systemlt email protected.The myhostname parameter is supposed to contain the your mail server name as indicated by your mx record.This is the name that Postfix uses in smtp communication to identify itself.For example HELO myhostname.If you set myhostname to a certain domain, then you should be able to setup the SPF records for that domain later.This is dictated by the SPF specifications.You might as well leave myhostname to just localhost and things would still work just fine.However in that case your server would use a message like HELO localhost when connecting to other mail servers like gmail, and gmail would angrily reject the mail calling it unsolicited.Therefore it is recommended to configure myhostname to a proper domain name with valid A and TXT SPF records.Also make sure to set myorigin.Example configuration myhostname mail.Technically, on a single a server, you can use the same value of myorigin for myhostname.However in diverse setups involving multiple separate servers, the values of these fields need to setup more carefully.To learn more read the Postfix basic configuration guide.Configure the LMTP socket main.The virtualtransport parameter tells postfix to forwardtransport the mails to dovecot for those domains that are listed in virtualmailboxdomains.Handing off local delivery to Dovecots LMTP.The path privatedovecot lmtp is relative to varspoolpostfix.The actual unix socket shall be configured later in the Dovecot configuration section.Configure SASL main.Here we set the parameters to setup SASL based authentication for Postfix.Postfix internally is capable of talking to Dovecots SASL service via a unix socket.Enabling SMTP for authenticated users, and handing off authentication to Dovecot.To check what different smtpdsasltype plugins your installation of Postfix supports run the following command.Add mailbox domains main.Over here we specify the domains for which Postfix shall accept incoming mails.So specify all your inhouse domains over here.We shall be putting the domains in a file named virtualmailboxdomains.Virtual domains, users, and aliases.Enter the domains, one in a lineexample.OK. mysite. com OKThen run postmap on the file.It will create a file named virtualmailboxdomains.Postfix postmap etcpostfixvirtualmailboxdomains.The virtualmailboxmaps table can be used to specify valid email addresses for the domains listed in virtualmailboxdomains.However this is not necessary, since the SASL authentication via Dovecot would be doing the verification.Enable SMTPS and MSA master.In addition to the smtp service on port 2.SMTPS will operate on port 4.MSA Mail submission Agent will operate on port 5.SMTP uses SSLTLS authentication type and MSA uses STARTTLS.Find the section on submission and smtps in the file named etcpostfixmaster.The Ultimate Guide to Web Hosting from Who.Is. Hosting. This.Chapter 1 What is Web Hosting Most people never really think about where a website is, or even what a website is.I turn on my computer, open a browser, and go to Google or Amazon or Yahoo.But what am I doing when I visit a website If Im a visitor, where have I goneAnd if it is a site, where is it located What will you learn in this chapter What a website really is.Three different types of websites and why theyre mostly the same.Where a website lives.What a hosting company is.Skip this chapter if You have used web hosting before and have a good understanding of what a website is and how they work.What is a websiteTo understand where a website is located, its helpful to understand what it is.We can roughly divide websites into three types there is some overlap here these are not strict categories, but they are helpful for thinking about this Collection of documents or pages This is the original type of website.Every page is a file in a public facing directory.When you look at a web page, your computer is literally downloading the file and showing it to you.Web application Google, your web based email provider, Facebook, and any online games you might play are all examples of web applications.Much like apps you run on your phone, tablet, or desktop, the files for the app have to exist somewhere.With web apps, they sit on public facing web server the same way documents and files do.Your browser downloads some of the files and runs them, and there is constant communication between your computer and the web server.Content management systems This is sort of a hybrid, and accounts for the vast majority of websites that exist today.The technology of a web application is used to simulate a collection of documents.If you read a blog, each blog post is probably not an individual file.Rather, the application is pulling the content out of a database and sending it to your browser as if it were a document, and your browser shows it to you without knowing any different.Theres some additional complications we dont really need to get into here, but the important thing is that when you visit a website, a series of things are happening Your computers browser sends a request to the websites server for something a page, a document, a file for running an application.The URL or address you put into the bar at the top of the browser window is the main portion of that request.The web server receives the request and pulls together whatever it needs to deliver back to you what you requested.This might just be an existing file, or it might be a piece of a web application, or it might be an assembled document from a content management system.The web server responds to the request with some kind of content.Your browser shows that content to you.Running a website.So, in order to run a website, you need a computer connected to the internet, that is capable of receiving requests, taking appropriate action, and responding.When people talk about servers for their website, this is all they are talking about.Computers that store the files needed to run a website, along with the software to deliver those files to anyone who asks for them.You could, in theory, run a website from your home desktop computer, but that would be a terrible idea.First off, youd have to know how to set it up properly to run a website which is not a trivial matter.Youd have to leave it on and connected to the internet all the time.Even if you could manage those things, your computer at home is only designed to deal with one user at a time.If a lot of people started trying to look at your website, your computer and your internet connection would both reach their limits and your website would stop working.Better than running a website on a personal desktop computer, you could buy a server.This is just a bigger, faster, better computer.Assuming you could afford it theyre expensive and assuming you could set it all up properly its not easy and assuming you could get a fast enough internet connection with a lot of bandwidth expensive and not always available, you could then run your website from that server.Obviously, this is a terrible idea.Too expensive, too complicated, too difficult.Web hosting companies.Web hosting companies have solved this problem for you.They have bought the big expensive computers, they have set them up to work for running a website, they have made sure they have a fast connection to the internet.Theyve done all the work.When you get a web hosting plan, you are borrowing a bit of one of their computers or a whole one, sometimes.This lets you put the files and software needed to run your website somewhere that it can easily be accessed by anyone who wants to view it.To make this easier for you, they also provide tools for managing your piece of the computer and for building and running your website.When you use a web hosting company for your website, your website isnt in a cloud somewhere or floating in an alternate dimension. Microsoft Exchange 2003 And 2007 San Diego . It is a collection of real, actual computer files sitting on a real actual computer somewhere, in a real building.Where that building is, and what that computer looks like will depend on which hosting company you use.And you may never see the computer or even know where in the world it is.But its not magic, and its not that much different than the computer you are using right now.Summary. A website is a collection of files that sit on a computer.For a website to work well, a regular desktop computer isnt a good choice.Web hosting companies provide fast, powerful computers so that anyone can run a website without having any special knowledge or buying any special equipment.Chapter 2 Different Types of Hosting.When you start looking to purchase a web hosting plan, its easy to start getting overwhelmed by all the different options available.Rather than trying to sort out what to buy while reading feature lists written by marketers, its better to start by figuring what kind of hosting you need.What will you learn in this chapter The difference between shared, dedicated, and VPS hosting.What cloud based hosting is.What managed hosting is, and why you may or may not need it.How to decide what type of hosting plan is right for you.Shared Hosting. The most common form of web hosting is called shared hosting.It is the least expensive and, as you might guess, the least powerful.With shared hosting, several web hosting customers share the same computer.All of the websites of all the different accounts are stored in the same drive, processed by the same CPU, and delivered by the same web server.Its easy to see why this is less expensive than other options.The hosting company is allocating relatively few resources to you.Of course, there are downsides.All the websites from all of the accounts are all competing for the same scarce computer resources.The servers that hold shared hosting plan sites are much larger and more powerful than your home computer, so they can host hundred of websites without any problem as long as none of the sites are too popular or need too many resources.Every page load, every image and asset file, requires a little bit of attention from the web server when someone requests it.If you are running a complex web application or a content management system, this could require more than a trivial amount processor power to query a database, assemble content into a page, or take some other action.Individually, these things can be so fast as to seem instantaneous.But multiplied over hundreds or thousands of visitors in a few minutes, and you have a recipe for site crashing.If the popular site is someone elses on the same server, youll experience performance lags and downtime without ever knowing why.If you are the lucky one getting a lot of traffic, you can expect your site to become unavailable right when you most need to shine.Additionally, you may find yourself running afoul of your hosting companys unstated but very much in force limitations on usage and bandwidth.The other downside to shared hosting is the inability to customize the hosting environment.This might not make any difference to you.If you are just running a straightforward Word.Press blog for example, you can get by just fine without having to tweak your environment.
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