From 27762d87178bee1405cf367f94c458e8f19ba329 Mon Sep 17 00:00:00 2001 From: Marc Fonvieille Date: Sat, 27 Mar 2004 09:54:50 +0000 Subject: [PATCH] - Various rewording/addition in DNS part (how to check a MX for example). - Update an sendmail FAQ excerpt PR: docs/64648 Submitted by: Marc Silver --- .../books/handbook/mail/chapter.sgml | 92 ++++++++++++------- 1 file changed, 60 insertions(+), 32 deletions(-) diff --git a/en_US.ISO8859-1/books/handbook/mail/chapter.sgml b/en_US.ISO8859-1/books/handbook/mail/chapter.sgml index b4d1e0f769..7f263244fe 100644 --- a/en_US.ISO8859-1/books/handbook/mail/chapter.sgml +++ b/en_US.ISO8859-1/books/handbook/mail/chapter.sgml @@ -171,27 +171,42 @@ exim - This is usually sendmail (by - default with FreeBSD) or one of the other mail server daemons such - as qmail, - postfix, or - exim. There are others, but those are - the most widely used. + &os; ships with sendmail by + default, but also support numerous other mail server daemons, + just some of which include: - The server daemon usually has two functions—it looks - after receiving incoming mail and delivers outgoing mail. It is - not responsible for allowing you to collect mail using protocols + + + exim; + + + + postfix; + + + + qmail. + + + + The server daemon usually has two functions—it is responsible + for receiving incoming mail as well as delivering outgoing mail. It is + not responsible for the collection of mail using protocols such as POP or IMAP to read your email, nor does it allow connecting to local mbox or Maildir mailboxes. You may require an additional daemon for that. - Be aware that some older versions of - sendmail have some serious security - problems, however as long as you run a current version of it you - should not have any problems. As always, it is a good idea to - stay up-to-date with any software you run. + + Older versions of sendmail + have some serious security issues which may result in an + attacker gaining local and/or remote access to your machine. + Make sure that you are running a current version to avoid + these problems. Optionally, install an alternative + MTA from the &os; + Ports Collection. + @@ -200,15 +215,25 @@ The Domain Name System (DNS) and its daemon named play a large role in the delivery of email. In order to deliver mail from your site to another, the - server daemon will look up the site in the DNS to determine the - host that will receive mail for the destination. + server daemon will look up the remote site in the DNS to determine the + host that will receive mail for the destination. This process + also occurs when mail is sent from a remote host to your mail + server. - It works the same way when you have mail sent to you. The DNS - contains the database mapping hostname to an IP address, and a - hostname to mailhost. The IP address is specified in an A record. - The MX (Mail eXchanger) record specifies the mailhost that will - receive mail for you. If you do not have an MX record for your - hostname, the mail will be delivered directly to your host. + DNS is responsible for mapping + hostnames to IP addresses, as well as for storing information + specific to mail delivery, known as MX records. The MX (Mail + eXchanger) record specifies which host, or hosts, will recieve + mail for a particular domain. If you do not have an MX record + for your hostname or domain, the mail will be delivered + directly to your host provided you have an A record pointing + your hostname to your IP address. + + You may view the MX records for any domain by using the + &man.host.1; command, as seen in the example below: + + &prompt.user; host -t mx FreeBSD.org +FreeBSD.org mail is handled (pri=10) by mx1.FreeBSD.org @@ -219,13 +244,15 @@ Receiving mail for your domain is done by the mail host. It - will collect mail sent to you and store it for reading or pickup - in either mbox or Maildir format, depending - on your configuration. Mail can then be remotely accessed using - either POP or IMAP, or - alternatively by using a mail user agent that is locally - installed on the mail host itself which will directly - communicate with the mailbox. This means that should you only + will collect all mail sent to your domain and store it + either in mbox (the default method for storing mail) or Maildir format, depending + on your configuration. + Once mail has been stored, it may either be read locally using + applications such as &man.mail.1; or + mutt, or remotely accessed and + collected using protocols such as + POP or IMAP. + This means that should you only wish to read mail locally, you are not required to install a POP or IMAP server. @@ -327,7 +354,7 @@ Mailboxes may be accessed locally by directly utilizing MUA's on the server on which the mailbox resides. This can be done using applications such as - mutt or mail. + mutt or &man.mail.1;. @@ -911,9 +938,9 @@ purgestat /usr/local/supermailer/bin/purgestat-compat This is answered in the sendmail FAQ as follows: - I am getting Local configuration error messages, such as: + I'm getting these error messages: -553 relay.domain.net config error: mail loops back to myself +553 MX list for domain.net points back to relay.domain.net 554 <user@domain.net>... Local configuration error How can I solve this problem? @@ -922,6 +949,7 @@ You have asked mail to the domain (e.g., domain.net) to be forwarded to a specific host (in this case, relay.domain.net) by using an MX record, but the relay machine does not recognize itself as domain.net. Add domain.net to /etc/mail/local-host-names +[known as /etc/sendmail.cw prior to version 8.10] (if you are using FEATURE(use_cw_file)) or add Cw domain.net to /etc/mail/sendmail.cf.