What is qmail server

Vpopmail allows us to do virtual domain mail hosting. You can install qmailadmin and administer your new pop mail system via a web interface. Or you can use the command line interface. A version is available now for use with vpopmail. Requirements: Qmail Vpopmail Autorespond 2. Login with the postmaster account and password for the domain that you created. Sqwebmail is a web based email client, similar to hotmail.

It is extremely efficient and the html is configurable. It is compatible with vpopmail. While different people may give you slightly different recommendations, you can ensure a safe backup of your qmail server if you backup the following 2 directories on a routine basis. If a host accepts mail for more than about 50 domains, Dan suggests that you put the 50 busiest into rcpthosts and the rest into morercpthosts.

In the past 20 years, most of the connectivity problems that require source routing have been solved, and for the ones that remain there are better tools such as smtproutes described later , so the percent hack is obsolete. If for some reason you absolutely need it you have an ancient mission-critical program for which all the source code has been lost that sends mail using the percent hack, perhaps any addresses in domains listed in percenthack are scanned for percent signs and rewritten.

In the previous example, out. If a domain listed in percenthack is also listed in rcpthosts , your system is an open relay, because spammers can send mail anywhere through your system by putting the actual target address in percent form inside an address in the listed domain.

Yes, spammers actually do so. If the domain part of an address in an injected message ends with a plus sign, the contents of plusdomain are appended to the end. In environments with many subdomains of a single main domain, say east. No longer widely used. A list of servers to which messages can be queued using QMQP. See Chapter Default: seconds a week. How long to keep trying to deliver a message. More precisely, if qmail tries to send a message and the attempt fails with a temporary error, the error is treated as permanent if the message is older than queuelifetime , in which case the message bounces.

Default: every domain. The list of domains for which this host accepts SMTP mail. It is extremely important that this file exist. When another hosts connects via SMTP to send you mail, the greeting string to send.

Explicit routes to use to deliver outgoing mail, overriding MX data. Each line is of one of these forms:. The domain can use wildcards; if it starts with a dot, it matches any target domain that ends with that domain. If relay is empty, qmail uses the standard MX lookup, letting you override a broader wildcard or smarthost route. Most systems can get by without smtproutes , but there are three situations where it can come in handy.

The second is to temporarily patch around broken MX records or mail relays. The third is to route mail for private domains within your network. Default: 60 seconds. How long to wait for a remote server to accept the initial connection to send mail. Default: seconds. Once a remote server is connected, how long to wait for each response before giving up.

The default of 20 minutes is extremely conservative, and can lead to all of your remote sending slots being tied up while waiting for somnolent remote hosts to time out. Unless you communicate with extraordinarily slow and overloaded remote servers, you can drop it to a minute. How long qmail-smtpd waits for each response from a remote client before timing out and giving up. As with timeoutremote , you can decrease this to a minute unless you have some really slow remote clients. The list of virtual users and domains for which this system receives mail.

The virtual domain scheme works by taking the mailbox in the virtual domain, prepending a string and a hyphen to create a local address, and redelivering the mail to the local address. The virtual domain file lists the prepend string to use for each virtual user and domain. Form 1 controls mail to a specific address. Forms 2 and 3 control mail to any address in a domain or in subdomains of a domain, respectively.

Form 4 , with an empty prepend, is used to create an exception to a domain that would otherwise be handled by a line of form 3 or 5 and means to handle the domain normally, not as a virtual domain. Form 5 is a catchall and controls all domains not listed in locals or elsewhere in virtualdomains.

If a domain erroneously appears both in locals and virtualdomains , the listing in locals takes precedence. Qmail handles this in a simple, elegant way with the alias pseudo-user. This makes any address not otherwise handled in effect a subaddress of alias, so you can handle addresses by putting. Since qmail handles deliveries using the. Also create. The most common thing to put in that file is a line to run the fastforward program see the next section to take delivery instructions from a file of addresses, roughly as sendmail does.

You can also implement other default delivery rules. It appears wrapped here, but it has to be on one long line in the file. This says that if an address contains a hyphen, strip off the hyphen and everything after it and redeliver it. Otherwise bounce the message. The bouncesaying command lets you provide your own failure message, but a simple exit would do the trick as well, telling qmail to bounce. This section describes fastforward Version 0.

The central program in the fastforward package is fastforward itself. The CDB file can refer to mailing list files of addresses; the difference is that the CDB file contains addresses and delivery instructions, while a mailing list file just contains a list of addresses and other mailing list files, for use within a delivery instruction. Mailing list files can be created by newinclude , which reads input containing a list of addresses in a format similar to the one sendmail uses for :include: files, or by setmaillist , which reads input in a more flexible format.

Mailing list files created by either program have the same format, so you can use the input format that is more convenient. Compiled mailing list files have the extension.

Or you can also combine it with other default rules. For example, to use fastforward and then redeliver mail to subaddresses to the base address of the subaddress:. In the absence of -p , fastforward exits 0 if it forwards the message and otherwise to bounce the mail.

The most common instruction forwards an address to one or more other addresses:. Mail to ted is forwarded to edward, edwin, and eduardo. This form is useful for role accounts that are handled by several people or tiny mailing lists that change rarely.

If there are multiple names in localhosts for this host, distinguish addresses by putting the domain of the address, and forward all addresses in a domain by using domain. This feature is more often used to handle addresses in virtual domains; see Chapter As a concession to sendmail compatibility, addresses can have comments and can be quoted as they are in To: and From: lines.

Any line that starts with is a comment, and any line can be continued by starting continuation lines with whitespace:. Any address that starts with a vertical bar is treated as a command for program delivery. If the command contains whitespace or at-signs, it has to be quoted. To run a program as another user, it has to be called from a. The program is run as:. Any address that starts with :include: refers to the contents of a mailing list file.

If there is an entry for both listname and owner-listname, any forwarded mail to listname has its envelope sender changed to owner-listname so bounces will go back to the owner of the list.

This means that, in the previous example, the addresses on the list belong to user fred, who can update the list file and rerun newinclude as needed. Mailing list files can refer to other mailing list files, but for security reasons and unlike sendmail , they cannot contain program deliveries.

This is not much of a problem in practice. Skip to main content. Start your free trial. Chapter 4. Getting Comfortable with Qmail. Mailboxes, Local Delivery, and Logging.

Mailbox Format. Local Delivery. An Excursion into Daemon Management. Starting a Daemon. Setting Up the Qmail Configuration Files. Starting and Stopping Qmail.

Choosing a Startup File. Example Stopping Qmail. Incoming Mail. Configuration Files. Setting Up the Daemons. Running the SMTP daemon. Make Some Mail Aliases. Relaying for Local Users.

Makefile to rebuild the rules file for the SMTP listener. Running the SMTP listener. Procmail and Qmail. Creating Addresses and Mailboxes. Reading Your Mail. Checking Your Configuration with qmail-showctl. Also in that directory is a program named sendmail, which takes the same input and parameters as the real Sendmail command but is actually just a wrapper for qmail-queue.

Webmin's module for configuring Qmail can be found under the Servers category. Assuming you have Qmail installed, clicking on its icon will take you to the module's main page shown in Figure Each of the icons on the main page page is a link to a page for one of the module's features, such as aliases or local domains. Under the name of each is the Qmail file or program name related to the feature, so that experienced administrators can see what each icon page is really configuring.

As their names suggest, they start the queue-processing daemon if it is not running, or stop it if it is running respectively. Because the Qmail SMTP listener is run from inetd, other hosts will always be able to connect to your system - however, any email that they send will not be delivered to local mailboxes or other servers if the queue-processing server is down.

The Qmail Configuration module. Unfortunately, very few operating systems include a Qmail package, so you will almost certainly need to download it from www. The installation process involves the creation of several Unix users and an inetd or xinetd service, both of which can be done using Webmin. It should be possible to compile Qmail on any Unix system, and its behaviour and installation location is the same on all of them.

As you would expect, this module behaves identically on all operating systems as well. If you install Qmail, you should also configure the POP3 server program qmail-pop3d that is included in the package. These can be easily installed using the Software Packages module, and will set up all the required users and Internet services for you. The developer of Qmail is reluctant to allow it to be packaged in formats other than the source. Before you can install Qmail, you will need to shut down or uninstall any other mail server installed on your system, such as Sendmail or Postfix.

This is necessary because only one program can listed on the SMTP port, and you want to be sure that the listener is always Qmail. Un-installation is the best option, because it ensures that all start-up scripts that might re-start Sendmail are deleted, and that the sendmail command can be linked to Qmail's wrapper program. When Qmail receives an email message via SMTP or one of its programs, it needs to work out if it should be delivered locally or forwarded to another server.

This is done by looking at the message's To address, specifically the domain part after the. The domain is compared a list of local domains, and if a match is found the email is delivered to the mailbox of the user whose name is to the left of the in the To address if it exists.

If the domain is not local, Qmail will look up the mail server for the domain and attempt to connect to it in order to transfer the message. This is what usually happens when a client on the same network connects to send out email. However, a problem will occur if your server attempts to connect back to itself, which can happen if the DNS says that it is the mail server for a domain which is not on its local domains list.

If this happens, a bounce message will be returned to the sender, containing text like that domain isn't in my list of allowed rcpthosts or too many hops. A mail alias tells your server that mail for a particular address should be forwarded to a different destination instead. That destination can be another email address, a local file, a directory or even the input to a program.

They can be useful for setting up pseudo mailboxes that actually send email to a real person, such as sales example. An alias can have the same name as a Unix user, in which case it will intercept all mail to that user and forward it to a different destination instead. As is usual in Webmin, you can edit an existing alias by clicking on its name in the list on the Mail Aliases page.

This will bring up an editing form that contains all the same fields as the creation form, but has Save and Delete buttons at the bottom instead.

The first of these will update the alias with any changes that you have made, while the second will permanently delete it. If a Unix user has a file named. If a file named. This module does not support the editing of per-user. However, Usermin does allow normal users to edit their own forwarding files using a web-based interface almost identical to the one described in this section. Qmail can be configured to restrict the destination domains to which it will relay email.

This is typically done to stop spammers using your system as an open mail relay, which allows them to hide their true addresses. However, there is no support in Qmail for allowing clients from certain addresses to relay, so setting up relay domain restrictions will make the server useless for sending outgoing email.