Sendmail with virtualhosts + procmail + dovecot under Ubuntu 11.04

Posted on 2011-09-10
Last Modified: 2012-05-12
Hello all,

I have switched from Red hat to an Ubuntu box and my current sendmail, dovecot and procmail settings that were working fine do not work anymore under Ubuntu. I've  been trying a lot of different settings but have not been able to be successful. I am copying here the config files so maybe someone can point out my errors.

The server is supposed to get emails from different domains as all their MX records point to it. So on my .mc file I have the CW option and also the generics_table and virtualtable.

The messages are not returning anymore, I can now see a huge amount at /var/spool/mqueue.

If I try to telnet to pop3 port 143, I get a deinal. If I try port 25 I am OK.

Here are my files:

/etc/procmailrc (I had this one created):

# file: /etc/procmailrc
# system-wide settings for procmail
SENDMAIL="/usr/sbin/sendmail -oi -t"
* ^X-Spam-Status: Yes


My /etc/dovecot/dovecot.conf:

## Dovecot 1.0 configuration file

# Default values are shown after each value, it's not required to uncomment
# any of the lines. Exception to this are paths, they're just examples
# with real defaults being based on configure options. The paths listed here
# are for configure --prefix=/usr --sysconfdir=/etc --localstatedir=/var
# --with-ssldir=/usr/share/ssl

# Base directory where to store runtime data.
# base_dir = /var/run/dovecot/

# Protocols we want to be serving:
#  imap imaps pop3 pop3s
protocols = imap imaps pop3 pop3s

# IP or host address where to listen in for connections. It's not currently
# possible to specify multiple addresses. "*" listens in all IPv4 interfaces.
# "[::]" listens in all IPv6 interfaces, but may also listen in all IPv4
# interfaces depending on the operating system. You can specify ports with
# "host:port".
imap_listen = *
pop3_listen = *

# IP or host address where to listen in for SSL connections. Defaults
# to above non-SSL equilevants if not specified.
#imaps_listen =
#pop3s_listen =

# Disable SSL/TLS support.
#ssl_disable = no

# PEM encoded X.509 SSL/TLS certificate and private key. They're opened before
# dropping root privileges, so keep the key file unreadable by anyone but
# root. Included doc/ can be used to easily generate self-signed
# certificate, just make sure to update the domains in dovecot-openssl.cnf
#ssl_cert_file = /usr/share/ssl/certs/dovecot.pem
#ssl_key_file = /usr/share/ssl/private/dovecot.pem

# SSL parameter file. Master process generates this file for login processes.
# It contains Diffie Hellman and RSA parameters.
#ssl_parameters_file = /var/run/dovecot/ssl-parameters.dat

# How often to regenerate the SSL parameters file. Generation is quite CPU
# intensive operation. The value is in hours, 0 disables regeneration
# entirely.
#ssl_parameters_regenerate = 24

# Disable LOGIN command and all other plaintext authentications unless
# SSL/TLS is used (LOGINDISABLED capability)
#disable_plaintext_auth = no

# Use this logfile instead of syslog(). /dev/stderr can be used if you want to
# use stderr for logging (ONLY /dev/stderr - otherwise it is closed).
#log_path =

# For informational messages, use this logfile instead of the default
#info_log_path =

# Prefix for each line written to log file. % codes are in strftime(3)
# format. Note the extra space at the end of line.
#log_timestamp = "%b %d %H:%M:%S "

## Login processes

# Directory where authentication process places authentication UNIX sockets
# which login needs to be able to connect to. The sockets are created when
# running as root, so you don't have to worry about permissions.
login_dir = /var/run/dovecot-login

# chroot login process to the login_dir. Only reason not to do this is if you
# wish to run the whole Dovecot without roots.
#login_chroot = yes

## IMAP login process

login = imap

# Executable location.
login_executable = /usr/libexec/dovecot/imap-login

# User to use for the login process. Create a completely new user for this,
# and don't use it anywhere else. The user must also belong to a group where
# only it has access, it's used to control access for authentication process.
#login_user = dovecot

# Set max. process size in megabytes. If you don't use
# login_process_per_connection you might need to grow this.
#login_process_size = 16

# Should each login be processed in it's own process (yes), or should one
# login process be allowed to process multiple connections (no)? Yes is more
# secure, espcially with SSL/TLS enabled. No is faster since there's no need
# to create processes all the time.
#login_process_per_connection = yes

# Number of login processes to create. If login_process_per_user is
# yes, this is the number of extra processes waiting for users to log in.
#login_processes_count = 3

# Maximum number of extra login processes to create. The extra process count
# usually stays at login_processes_count, but when multiple users start logging
# in at the same time more extra processes are created. To prevent fork-bombing
# we check only once in a second if new processes should be created - if all
# of them are used at the time, we double their amount until limit set by this
# setting is reached. This setting is used only if login_process_per_use is yes.
#login_max_processes_count = 128

# Maximum number of connections allowed in login state. When this limit is
# reached, the oldest connections are dropped. If login_process_per_user
# is no, this is a per-process value, so the absolute maximum number of users
# logging in actually login_processes_count * max_logging_users.
#login_max_logging_users = 256

## POP3 login process

# Settings default to same as above, so you don't have to set anything
# unless you want to override them.

login = pop3

# Exception to above rule being the executable location.
#login_executable = /usr/libexec/dovecot/pop3-login

## Mail processes

# Maximum number of running mail processes. When this limit is reached,
# new users aren't allowed to log in.
#max_mail_processes = 1024

# Show more verbose process titles (in ps). Currently shows user name and
# IP address. Useful for seeing who are actually using the IMAP processes
# (eg. shared mailboxes or if same uid is used for multiple accounts).
#verbose_proctitle = no

# Show protocol level SSL errors.
#verbose_ssl = no

# Valid UID range for users, defaults to 500 and above. This is mostly
# to make sure that users can't log in as daemons or other system users.
# Note that denying root logins is hardcoded to dovecot binary and can't
# be done even if first_valid_uid is set to 0.
#first_valid_uid = 500
#last_valid_uid = 0

# Valid GID range for users, defaults to non-root/wheel. Users having
# non-valid GID as primary group ID aren't allowed to log in. If user
# belongs to supplementary groups with non-valid GIDs, those groups are
# not set.
#first_valid_gid = 1
#last_valid_gid = 0

# ':' separated list of directories under which chrooting is allowed for mail
# processes (ie. /var/mail will allow chrooting to /var/mail/foo/bar too).
# This setting doesn't affect login_chroot or auth_chroot variables.
# WARNING: Never add directories here which local users can modify, that
# may lead to root exploit. Usually this should be done only if you don't
# allow shell access for users. See doc/configuration.txt for more information.
#valid_chroot_dirs =

# Default chroot directory for mail processes. This can be overridden by
# giving /./ in user's home directory (eg. /home/./user chroots into /home).
#mail_chroot =

# Default MAIL environment to use when it's not set. By leaving this empty
# dovecot tries to do some automatic detection as described in
# doc/mail-storages.txt. There's a few special variables you can use:
#   %u - username
#   %n - user part in user@domain, same as %u if there's no domain
#   %d - domain part in user@domain, empty if user there's no domain
#   %h - home directory
# You can also limit a width of string by giving the number of max. characters
# after the '%' character. For example %1u gives the first character of
# username. Some examples:
#   maildir:/var/mail/%1u/%u/Maildir
#   mbox:~/mail/:INBOX=/var/mail/%u
#   mbox:/var/mail/%d/%n/:INDEX=/var/indexes/%d/%n
#default_mail_env =

# Space-separated list of fields to cache for all mails. Currently these
# fields are allowed followed by a list of commands they speed up:
#                  HEADER IN-REPLY-TO
#  Body          - FETCH BODY
#  MessagePart   - FETCH BODY[1.2.3] (ie. body parts), RFC822.SIZE,
#                  SEARCH SMALLER, LARGER, also speeds up BODY/BODYSTRUCTURE
#                  generation. This is always set with mbox mailboxes, and
#                  also default with Maildir.
# Different IMAP clients work in different ways, that's why Dovecot by default
# only caches MessagePart which speeds up most operations. Whenever client
# does something where caching could be used, the field is automatically marked
# to be cached later. For example after FETCH BODY the BODY will be cached
# for all new messages. Normally you should leave this alone, unless you know
# what most of your IMAP clients are. Caching more fields than needed makes
# the index files larger and generate useless I/O.
# With maildir there's one extra optimization - if nothing is cached, indexing
# the maildir becomes much faster since it's not opening any of the mail files.
# This could be useful if your IMAP clients access only new mails.

#mail_cache_fields = MessagePart

# Space-separated list of fields that Dovecot should never set to be cached.
# Useful if you want to save disk space at the cost of more I/O when the fields
# needed.
#mail_never_cache_fields =

# Workarounds for various client bugs:
#   oe6-fetch-no-newmail:
#     Never send EXISTS/RECENT when replying to FETCH command. Outlook Express
#     seems to think they are FETCH replies and gives user "Message no longer
#     in server" error. Note that OE6 still breaks even with this workaround
#     if synchronization is set to "Headers Only".
#   outlook-idle:
#     Outlook and Outlook Express never abort IDLE command, so if no mail
#     arrives in half a hour, Dovecot closes the connection. This is still
#     fine, except Outlook doesn't connect back so you don't see if new mail
#     arrives.
#client_workarounds =

# Dovecot can notify client of new mail in selected mailbox soon after it's
# received. This setting specifies the minimum interval in seconds between
# new mail notifications to client - internally they may be checked more or
# less often. Setting this to 0 disables the checking.
# NOTE: Evolution client breaks with this option when it's trying to APPEND.
#mailbox_check_interval = 0

# Like mailbox_check_interval, but used for IDLE command.
#mailbox_idle_check_interval = 30

# Allow full filesystem access to clients. There's no access checks other than
# what the operating system does for the active UID/GID. It works with both
# maildir and mboxes, allowing you to prefix mailboxes names with eg. /path/
# or ~user/.
#mail_full_filesystem_access = no

# Maximum allowed length for custom flag name. It's only forced when trying
# to create new flags.
#mail_max_flag_length = 50

# Save mails with CR+LF instead of plain LF. This makes sending those mails
# take less CPU, especially with sendfile() syscall with Linux and FreeBSD.
# But it also creates a bit more disk I/O which may just make it slower.
#mail_save_crlf = no

# Use mmap() instead of read() to read mail files. read() seems to be a bit
# faster with my Linux/x86 and it's better with NFS, so that's the default.
#mail_read_mmaped = no

# Copy mail to another folders using hard links. This is much faster than
# actually copying the file. This is problematic only if something modifies
# the mail in one folder but doesn't want it modified in the others. I don't
# know any MUA which would modify mail files directly. IMAP protocol also
# requires that the mails don't change, so it would be problematic in any case.
# If you care about performance, enable it.
#maildir_copy_with_hardlinks = no

# Check if mails' content has been changed by external programs. This slows
# down things as extra stat() needs to be called for each file. If changes are
# noticed, the message is treated as a new message, since IMAP protocol
# specifies that existing message are immutable.
#maildir_check_content_changes = no

# Which locking methods to use for locking mbox. There's three available:
#  dotlock: Create <mailbox>.lock file. This is the oldest and most NFS-safe
#           solution. If you want to use /var/mail/ like directory, the users
#           will need write access to that directory.
#  fcntl  : Use this if possible. Works with NFS too if lockd is used.
#  flock  : May not exist in all systems. Doesn't work with NFS.
# You can use both fcntl and flock too; if you do the order they're declared
# with is important to avoid deadlocks if other MTAs/MUAs are using both fcntl
# and flock. Some operating systems don't allow using both of them
# simultaneously, eg. BSDs. If dotlock is used, it's always created first.
mbox_locks = fcntl

# Should we create dotlock file even when we want only a read-lock? Setting
# this to yes hurts the performance when the mailbox is accessed simultaneously
# by multiple processes, but it's needed for reliable reading if no other
# locking methods are available.
#mbox_read_dotlock = no

# Maximum time in seconds to wait for lock (all of them) before aborting.
#mbox_lock_timeout = 300

# If dotlock exists but the mailbox isn't modified in any way, override the
# lock file after this many seconds.
#mbox_dotlock_change_timeout = 30

# umask to use for mail files and directories
#umask = 0077

# Drop all privileges before exec()ing the mail process. This is mostly
# meant for debugging, otherwise you don't get core dumps. Note that setting
# this to yes means that log file is opened as the logged in user, which
# might not work. It could also be a small security risk if you use single UID
# for multiple users, as the users could ptrace() each others processes then.
#mail_drop_priv_before_exec = no

## IMAP process

# Executable location
imap_executable = /usr/libexec/dovecot/imap

# Set max. process size in megabytes. Most of the memory goes to mmap()ing
# files, so it shouldn't harm much even if this limit is set pretty high.
#imap_process_size = 256

# Support for dynamically loadable modules.
#imap_use_modules = no
#imap_modules = /usr/lib/dovecot/imap

## POP3 process

# Executable location
pop3_executable = /usr/libexec/dovecot/pop3

# Set max. process size in megabytes. Most of the memory goes to mmap()ing
# files, so it shouldn't harm much even if this limit is set pretty high.
#pop3_process_size = 256

# Support for dynamically loadable modules.
#pop3_use_modules = no
#pop3_modules = /usr/lib/dovecot/pop3

## Authentication processes

# You can have multiple processes; each time "auth = xx" is seen, a new
# process definition is started. The point of multiple processes is to be
# able to set stricter permissions to others. For example, plain/PAM
# authentication requires roots, but if you also use digest-md5 authentication
# for some users, you can authenticate them without any privileges in a
# separate auth process. Just remember that only one auth process is asked
# for the password, so you can't have different passwords with different
# processes (unless they have different auth methods, and you're ok with
# having different password for each method).

# Authentication process name.
auth = default

# Space separated list of wanted authentication mechanisms:
#   plain digest-md5 anonymous
auth_mechanisms = plain

# Space separated list of realms for SASL authentication mechanisms that need
# them. You can leave it empty if you don't want to support multiple realms.
# Many clients simply use the first one listed here, so keep the default realm
# first.
#auth_realms =

# Default realm to use if none was specified.
#auth_default_realm =

# Where user database is kept:
#   passwd: /etc/passwd or similiar, using getpwnam()
#   passwd-file <path>: passwd-like file with specified location
#   static uid=<uid> gid=<gid> home=<dir template>: static settings
#   vpopmail: vpopmail library
#   ldap <config path>: LDAP, see doc/dovecot-ldap.conf
#   pgsql <config path>: a PostgreSQL database, see doc/dovecot-pgsql.conf
auth_userdb = passwd
# auth_userdb = pgsql /usr/local/etc/dovecot-pgsql.conf

# Where password database is kept:
#   passwd: /etc/passwd or similiar, using getpwnam()
#   shadow: /etc/shadow or similiar, using getspnam()
#   pam [<service> | *]: PAM authentication
#   passwd-file <path>: passwd-like file with specified location
#   vpopmail: vpopmail authentication
#   ldap <config path>: LDAP, see doc/dovecot-ldap.conf
#   pgsql <config path>: a PostgreSQL database, see doc/dovecot-pgsql.conf
# auth_passdb = pgsql /usr/local/etc/dovecot-pgsql.conf
auth_passdb = pam

#auth_executable = /usr/libexec/dovecot/dovecot-auth

# Set max. process size in megabytes.
#auth_process_size = 256

# User to use for the process. This user needs access to only user and
# password databases, nothing else. Only shadow and pam authentication
# requires roots, so use something else if possible.
auth_user = root

# Directory where to chroot the process. Most authentication backends don't
# work if this is set, and there's no point chrooting if auth_user is root.
#auth_chroot =

# Number of authentication processes to create
#auth_count = 1

# List of allowed characters in username. If the user-given username contains
# a character not listed in here, the login automatically fails. This is just
# an extra check to make sure user can't exploit any potential quote escaping
# vulnerabilities with SQL/LDAP databases. If you want to allow all characters,
# set this value to empty.
#auth_username_chars = abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ01234567890.-_@

# Username to use for users logging in with ANONYMOUS SASL mechanism
#auth_anonymous_username = anonymous

# More verbose logging. Useful for figuring out why authentication isn't
# working.
#auth_verbose = no

# digest-md5 authentication process. It requires special MD5 passwords which
# /etc/shadow and PAM doesn't support, so we never need roots to handle it.
# Note that the passwd-file is opened before chrooting and dropping root
# privileges, so it may be 0600-root owned file.

#auth = digest_md5
#auth_methods = digest-md5
#auth_realms =
#auth_userdb = passwd-file /etc/passwd.imap
#auth_passdb = passwd-file /etc/passwd.imap
#auth_user = imapauth
#auth_chroot =

# if you plan to use only passwd-file, you don't need the two auth processes,
# simply set "auth_methods = plain digest-md5"


dnl 14/11/2000 configuracao com virtualhosts
dnl       O doc de explicacao se encontra em /usr/lib/sendmail-cf/README
dnl a estrutura de um arquivo mc deve estar na seguinte ordem
dnl      VERSIONID
dnl      OSTYPE
dnl      DOMAIN quando tem apenas um dominio
dnl      define(s) que sao respectivos a FEATURE(s)
dnl      FEATURE
dnl      local macro definitions
dnl      MAILER
dnl      LOCAL_RULE_*
dnl Abaixo segue arquivo com respectivas explicacoes e comentarios
dnl divert(-1) apaga o crud no arquivo .cf resultante
dnl para gerar o arquivo .cf deve rodar o comando :
dnl        m4 /etc/ > /etc/
dnl You will need to have the sendmail-cf package installed for this to
dnl work
dnl inclui as diretivas para gerar arquivos .cf com o M4 preprocessor
dnl /usr/share/sendmail/cf/m4/cf.m4
dnl # Items controlled by /etc/mail/sendmail.conf - DO NOT TOUCH HERE
undefine(`confHOST_STATUS_DIRECTORY')dnl            #DAEMON_HOSTSTATS
dnl # Items controlled by /etc/mail/sendmail.conf - DO NOT TOUCH HERE
dnl macro que coloca informacoes da versao no greeting do SMTP
VERSIONID(`$Id:, v 8.14.4-2ubuntu1 2011-01-10 21:47:09 cowboy Exp $')dnl
dnl definde de onde pode receber
DAEMON_OPTIONS(`Family=inet,  Name=MTA-v4, Port=smtp')dnl
dnl configura pathnames help, status files and flags local mailer do OS
dnl DefaultUser [1:1] Default user id.
dnl nao faz relay UUCP
dnl nao faz BITNET relay
dnl Auto Rebuild Aliases
dnl define(`confAUTO_REBUILD')dnl
dnl aplica na primeira tentativa de conectar o servidor como Timeout.connect
define(`confTO_CONNECT', `1m')dnl
dnl nao tenta conectar ao host diretamente
dnl nao inserir nomes e enderecos de interafaces locais
dnl define onde esta o procmail para FEATURE(local_procmail)
dnl adicionado set 10 2011
FEATURE(local_procmail,`',`procmail -t -Y -a $h -d $u')dnl
dnl define onde esta o arquivo de alias para enderecos locais
dnl onde esta o contendo informacoes de status
define(`STATUS_FILE', `/var/log/')dnl
dnl tam maximo aceito de mensagem transmitida via UUCP
define(`UUCP_MAILER_MAX', `2000000')dnl
dnl user database specification
define(`confUSERDB_SPEC', `/etc/mail/userdb.db')dnl
dnl privacy flags e opcoes
define(`confPRIVACY_FLAGS', `authwarnings,novrfy,noexpn')dnl
dnl o tempo ate ser enviado ao sender que a mensagem nao foi entregue
define(`confTO_QUEUEWARN', `4h')dnl
dnl o tempo ate uma mensagem ser retornada como nao entregue
define(`confTO_QUEUERETURN', `2d')dnl
dnl os flags usados pelo local mailer
dnl argumentos passados para entregar local mail
define(`LOCAL_MAILER_ARGS', `procmail -a $h -d $u')dnl
dnl define(`confQUEUE_LA', `12')dnl
dnl define(`confREFUSE_LA', `18')dnl
dnl use o sendmail restricted shell que veio com a distro
dnl FEATURE(`smrsh',`/usr/sbin/smrsh')dnl
dnl mailer table para rooting a dominios particulares que nao estao na class w
FEATURE(`mailertable',`hash -o /etc/mail/mailertable')dnl
dnl para aliases a multiplos dominios ender global para endereco local
FEATURE(`virtusertable',`hash -o /etc/mail/virtusertable')dnl
dnl reverso, end local para global
FEATURE(`genericstable',`hash -o /etc/mail/genericstable')dnl
dnl especifica os dominios usados em genericstable
dnl rejeita todo mail enderecado "address.REDIRECT"
dnl sempre incluir dominio mesmo para entrega local host
dnl usar o arquivo cw para nomes alternados para esse host
dnl FEATURE(use_cw_file)dnl
dnl define(`confCW_FILE',`/etc/mail/')dnl
dnl localizacao do arquivo cw para dominios
define(`confCW_FILE', `-o /etc/mail/local-host-names')dnl
dnl mascarado de acordo com dominios, mascara e-mails com esses dominios
dnl usar procmail como MDA para e-mails locais
dnl banco de dados para aceitar, rejeitar, relay de enderecos dominios.
dnl black list para nao aceitar e-mails desses enderecos ou dominios.
dnl masquerade todos os hosts dentro de um dominio
dnl masquerade no envelope
dnl mascara o sender tambem
dnl We strongly recommend to comment this one out if you want to protect
dnl yourself from spam. However, the laptop and users on computers that do
dnl not hav 24x7 DNS do need this.
dnl FEATURE(`accept_unresolvable_domains')dnl
dnl FEATURE(`relay_based_on_MX')dnl
dnl MAILER(smtp) deve vir sempre depois de MAILER(local)
Question by:CarlosScheidecker
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LVL 11

Expert Comment

ID: 36518185
I have tried a few times on Ubuntu to get what you need working and found my time was being eaten away so found a solution that works perfectly.

Author Comment

ID: 36518194
I have as a requirement run sendmail.

It seems I got Sendmail to work,  however Dovecot will not start. I cannot know why as I have no logs for it.
LVL 11

Expert Comment

ID: 36518211
When you are using telnet to connect are you doing that on the server or on a remote station ?

Have you done a netstat -ta to see if it is listening ?

use tail -f on the system logs while starting dovecot and see if there are any errors

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Author Comment

ID: 36518215
Yes, netstat and nmap just gives me ssh and smtp ports.

Dovecot show this:

Sep 11 00:41:38 ns3 init: dovecot main process (17658) terminated with status 89

LVL 11

Expert Comment

ID: 36518250
Have a look here :

Basically it suggests that the do not have equal amounts of open and closing braces in your conf file, dovecot.conf  (Braces are {} )
LVL 11

Expert Comment

ID: 36518257
You do need to setup your ssl with your current config as you have :

protocols = imap imaps pop3 pop3s

if you do not want ssl change it to

protocols = imap pop3
LVL 11

Accepted Solution

maeltar earned 500 total points
ID: 36518260
you also need to setup the imap user correctly...

login = imap

# Executable location.
login_executable = /usr/libexec/dovecot/imap-login

# User to use for the login process. Create a completely new user for this,
# and don't use it anywhere else. The user must also belong to a group where
# only it has access, it's used to control access for authentication process.
#login_user = dovecot

Open in new window


Author Comment

ID: 36518268
Yes Maeltar. Just did that!

Then used dovecot --log-error to look at errors at my config.

So Dovecot is now up!
LVL 11

Expert Comment

ID: 36518274
excellent news :D

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Learn how to navigate the file tree with the shell. Use pwd to print the current working directory: Use ls to list a directory's contents: Use cd to change to a new directory: Use wildcards instead of typing out long directory names: Use ../ to move…

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