## Dovecot configuration file # NOTICE FOR CPANEL SYSTEMS # On cPanel servers this file is generated by combining a # template at /var/cpanel/templates/dovecot/main.default # and a datastore at /var/cpanel/conf/dovecot/main # # The template may be customized by making a copy of it at # /var/cpanel/templates/dovecot/main.local # similar to the way in which httpd.conf can be customized # # Direct edits of the rendered dovecot.conf file will not # be preserved when dovecot is updated. Use the # "Mailserver Configuration" interface in WebHostManager instead. # If you're in a hurry, see http://wiki2.dovecot.org/QuickConfiguration # "doveconf -n" command gives a clean output of the changed settings. Use it # instead of copy&pasting files when posting to the Dovecot mailing list. # '#' character and everything after it is treated as comments. Extra spaces # and tabs are ignored. If you want to use either of these explicitly, put the # value inside quotes, eg.: key = "# char and trailing whitespace " # Most (but not all) settings can be overridden by different protocols and/or # source/destination IPs by placing the settings inside sections, for example: # protocol imap { }, local 127.0.0.1 { }, remote 10.0.0.0/8 { } # Default values are shown for each setting, it's not required to uncomment # those. These are exceptions to this though: No sections (e.g. namespace {}) # or plugin settings are added by default, they're listed only as examples. # Paths are also just examples with the real defaults being based on configure # options. The paths listed here are for configure --prefix=/usr # --sysconfdir=/etc --localstatedir=/var # Base directory where to store runtime data. #base_dir = /var/run/dovecot # Protocols we want to be serving: imap pop3 # If you only want to use dovecot-auth, you can set this to "none". protocols = lmtp imap pop3 # A comma separated list of IPs or hosts where to listen in for connections. # "*" listens in all IPv4 interfaces, "::" listens in all IPv6 interfaces. # If you want to specify non-default ports or anything more complex, # edit conf.d/master.conf. #listen = *, :: # Should all IMAP and POP3 processes be killed when Dovecot master process # shuts down. Setting this to "no" means that Dovecot can be upgraded without # forcing existing client connections to close (although that could also be # a problem if the upgrade is eg. because of a security fix). This however # means that after master process has died, the client processes can't write # to log files anymore. #shutdown_clients = yes verbose_proctitle = no # SSL DH parameters # Generate new params with `openssl dhparam -out /etc/dovecot/dh.pem 4096` # Or migrate from old ssl-parameters.dat file with the command dovecot # gives on startup when ssl_dh is unset. ssl_dh = to select which instance is used (an alternative # to -c ). The instance name is also added to Dovecot processes # in ps output. #instance_name = dovecot # Greeting message for clients. #login_greeting = Dovecot ready. # Space separated list of trusted network ranges. Connections from these # IPs are allowed to override their IP addresses and ports (for logging and # for authentication checks). disable_plaintext_auth is also ignored for # these networks. Typically you'd specify your IMAP proxy servers here. #login_trusted_networks = # Space separated list of login access check sockets (e.g. tcpwrap) #login_access_sockets = # With proxy_maybe=yes if proxy destination matches any of these IPs, don't do # proxying. This isn't necessary normally, but may be useful if the destination # IP is e.g. a load balancer's IP. #auth_proxy_self = ## ## Mailbox locations and namespaces ## # Location for users' mailboxes. The default is empty, which means that Dovecot # tries to find the mailboxes automatically. This won't work if the user # doesn't yet have any mail, so you should explicitly tell Dovecot the full # location. # # If you're using mbox, giving a path to the INBOX file (eg. /var/mail/%u) # isn't enough. You'll also need to tell Dovecot where the other mailboxes are # kept. This is called the "root mail directory", and it must be the first # path given in the mail_location setting. # # There are a few special variables you can use, eg.: # # %u - username # %n - user part in user@domain, same as %u if there's no domain # %d - domain part in user@domain, empty if there's no domain # %h - home directory # # See doc/wiki/Variables.txt for full list. Some examples: # # mail_location = maildir:~/Maildir # mail_location = mbox:~/mail:INBOX=/var/mail/%u # mail_location = mbox:/var/mail/%d/%1n/%n:INDEX=/var/indexes/%d/%1n/%n # # # #mail_location = namespace inbox { type = private # Hierarchy separator to use. You should use the same separator for all # namespaces or some clients get confused. '/' is usually a good one. # The default however depends on the underlying mail storage format. separator = . # Prefix required to access this namespace. This needs to be different for # all namespaces. For example "Public/". prefix = INBOX. # Physical location of the mailbox. This is in same format as # mail_location, which is also the default for it. #location = # There can be only one INBOX, and this setting defines which namespace # has it. inbox = yes # If namespace is hidden, it's not advertised to clients via NAMESPACE # extension. You'll most likely also want to set list=no. This is mostly # useful when converting from another server with different namespaces which # you want to deprecate but still keep working. For example you can create # hidden namespaces with prefixes "~/mail/", "~%u/mail/" and "mail/". #hidden = yes # Show the mailboxes under this namespace with LIST command. This makes the # namespace visible for clients that don't support NAMESPACE extension. # "children" value lists child mailboxes, but hides the namespace prefix. #list = yes # Namespace handles its own subscriptions. If set to "no", the parent # namespace handles them (empty prefix should always have this as "yes") #subscriptions = yes #subscriptions = yes mailbox Drafts { special_use = \Drafts auto = subscribe } mailbox spam { special_use = \Junk auto = subscribe } mailbox Trash { special_use = \Trash auto = subscribe } mailbox Sent { special_use = \Sent auto = subscribe } mailbox "Sent Messages" { special_use = \Sent auto = no } mailbox Archive { special_use = \Archive auto = create } mailbox "Archives" { special_use = \Archive auto = no } } # Example shared namespace configuration #namespace { #type = shared #separator = / # Mailboxes are visible under "shared/user@domain/" # %%n, %%d and %%u are expanded to the destination user. #prefix = shared/%%u/ # Mail location for other users' mailboxes. Note that %variables and ~/ # expands to the logged in user's data. %%n, %%d, %%u and %%h expand to the # destination user's data. #location = maildir:%%h/Maildir:INDEX=~/Maildir/shared/%%u # Use the default namespace for saving subscriptions. #subscriptions = no # List the shared/ namespace only if there are visible shared mailboxes. #list = children #} # Should shared INBOX be visible as "shared/user" or "shared/user/INBOX"? #mail_shared_explicit_inbox = no # System user and group used to access mails. If you use multiple, userdb # can override these by returning uid or gid fields. You can use either numbers # or names. #mail_uid = #mail_gid = # Group to enable temporarily for privileged operations. Currently this is # used only with INBOX when either its initial creation or dotlocking fails. # Typically this is set to "mail" to give access to /var/mail. #mail_privileged_group = # Grant access to these supplementary groups for mail processes. Typically # these are used to set up access to shared mailboxes. Note that it may be # dangerous to set these if users can create symlinks (e.g. if "mail" group is # set here, ln -s /var/mail ~/mail/var could allow a user to delete others' # mailboxes, or ln -s /secret/shared/box ~/mail/mybox would allow reading it). #mail_access_groups = # 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 # Dictionary for key=value mailbox attributes. This is used for example by # URLAUTH and METADATA extensions. #mail_attribute_dict = # A comment or note that is associated with the server. This value is # accessible for authenticated users through the IMAP METADATA server # entry "/shared/comment". #mail_server_comment = "" # Indicates a method for contacting the server administrator. According to # RFC 5464, this value MUST be a URI (e.g., a mailto: or tel: URL), but that # is currently not enforced. Use for example mailto:admin@example.com. This # value is accessible for authenticated users through the IMAP METADATA server # entry "/shared/admin". #mail_server_admin = ## ## Mail processes ## # Don't use mmap() at all. This is required if you store indexes to shared # filesystems (NFS or clustered filesystem). #mmap_disable = no # Rely on O_EXCL to work when creating dotlock files. NFS supports O_EXCL # since version 3, so this should be safe to use nowadays by default. #dotlock_use_excl = yes # When to use fsync() or fdatasync() calls: # optimized (default): Whenever necessary to avoid losing important data # always: Useful with e.g. NFS when write()s are delayed # never: Never use it (best performance, but crashes can lose data) #mail_fsync = optimized # Mail storage exists in NFS. Set this to yes to make Dovecot flush NFS caches # whenever needed. If you're using only a single mail server this isn't needed. #mail_nfs_storage = no # Mail index files also exist in NFS. Setting this to yes requires # mmap_disable=yes and fsync_disable=no. #mail_nfs_index = no # Locking method for index files. Alternatives are fcntl, flock and dotlock. # Dotlocking uses some tricks which may create more disk I/O than other locking # methods. NFS users: flock doesn't work, remember to change mmap_disable. #lock_method = fcntl # 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 # Directory where mails can be temporarily stored. Usually it's used only for # mails larger than >= 128 kB. It's used by various parts of Dovecot, for # example LDA/LMTP while delivering large mails or zlib plugin for keeping # uncompressed mails. #mail_temp_dir = /tmp # 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 = 201 #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 # Maximum allowed length for mail keyword name. It's only forced when trying # to create new keywords. #mail_max_keyword_length = 50 # ':' 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, mail_chroot or auth chroot # settings. If this setting is empty, "/./" in home dirs are ignored. # 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. #valid_chroot_dirs = # Default chroot directory for mail processes. This can be overridden for # specific users in user database by giving /./ in user's home directory # (eg. /home/./user chroots into /home). Note that usually there is no real # need to do chrooting, Dovecot doesn't allow users to access files outside # their mail directory anyway. If your home directories are prefixed with # the chroot directory, append "/." to mail_chroot. #mail_chroot = # UNIX socket path to master authentication server to find users. # This is used by imap (for shared users) and lda. #auth_socket_path = /var/run/dovecot/auth-userdb # Directory where to look up mail plugins. #mail_plugin_dir = /usr/lib/dovecot # Space separated list of plugins to load for all services. Plugins specific to # IMAP, LDA, etc. are added to this list in their own .conf files. # Quota support must be enabled globally for the quota-status # service to work mail_plugins = quota quota_clone zlib ## ## Mailbox handling optimizations ## # Mailbox list indexes can be used to optimize IMAP STATUS commands. They are # also required for IMAP NOTIFY extension to be enabled. mailbox_list_index = yes # Trust mailbox list index to be up-to-date. This reduces disk I/O at the cost # of potentially returning out-of-date results after e.g. server crashes. # The results will be automatically fixed once the folders are opened. #mailbox_list_index_very_dirty_syncs = yes # Should INBOX be kept up-to-date in the mailbox list index? By default it's # not, because most of the mailbox accesses will open INBOX anyway. #mailbox_list_index_include_inbox = no # The minimum number of mails in a mailbox before updates are done to cache # file. This allows optimizing Dovecot's behavior to do less disk writes at # the cost of more disk reads. #mail_cache_min_mail_count = 0 # When IDLE command is running, mailbox is checked once in a while to see if # there are any new mails or other changes. This setting defines the minimum # time to wait between those checks. Dovecot can also use inotify and # kqueue to find out immediately when changes occur. mailbox_idle_check_interval = 30 secs # 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. # Also note that if other software reads the mboxes/maildirs, they may handle # the extra CRs wrong and cause problems. #mail_save_crlf = no # Max number of mails to keep open and prefetch to memory. This only works with # some mailbox formats and/or operating systems. mail_prefetch_count = 20 # How often to scan for stale temporary files and delete them (0 = never). # These should exist only after Dovecot dies in the middle of saving mails. #mail_temp_scan_interval = 1w # How many slow mail accesses sorting can perform before it returns failure. # With IMAP the reply is: NO [LIMIT] Requested sort would have taken too long. # The untagged SORT reply is still returned, but it's likely not correct. #mail_sort_max_read_count = 0 protocol !indexer-worker { # If folder vsize calculation requires opening more than this many mails from # disk (i.e. mail sizes aren't in cache already), return failure and finish # the calculation via indexer process. Disabled by default. This setting must # be 0 for indexer-worker processes. #mail_vsize_bg_after_count = 0 } ## ## Maildir-specific settings ## # By default LIST command returns all entries in maildir beginning with a dot. # Enabling this option makes Dovecot return only entries which are directories. # This is done by stat()ing each entry, so it causes more disk I/O. # (For systems setting struct dirent->d_type, this check is free and it's # done always regardless of this setting) #maildir_stat_dirs = no # When copying a message, do it with hard links whenever possible. This makes # the performance much better, and it's unlikely to have any side effects. maildir_copy_with_hardlinks = yes # Assume Dovecot is the only MUA accessing Maildir: Scan cur/ directory only # when its mtime changes unexpectedly or when we can't find the mail otherwise. maildir_very_dirty_syncs = yes # If enabled, Dovecot doesn't use the S= in the Maildir filenames for # getting the mail's physical size, except when recalculating Maildir++ quota. # This can be useful in systems where a lot of the Maildir filenames have a # broken size. The performance hit for enabling this is very small. maildir_broken_filename_sizes = yes # Always move mails from new/ directory to cur/, even when the \Recent flags # aren't being reset. #maildir_empty_new = no ## ## mdbox-specific settings ## # Maximum dbox file size until it's rotated. mdbox_rotate_size = 10M # Maximum dbox file age until it's rotated. Typically in days. Day begins # from midnight, so 1d = today, 2d = yesterday, etc. 0 = check disabled. # When creating new mdbox files, immediately preallocate their size to # mdbox_rotate_size. This setting currently works only in Linux with some # filesystems (ext4, xfs). #mdbox_preallocate_space = no ## ## IMAP specific settings ## protocol imap { # If nothing happens for this long while client is IDLEing, move the connection # to imap-hibernate process and close the old imap process. This saves memory, # because connections use very little memory in imap-hibernate process. The # downside is that recreating the imap process back uses some resources. imap_hibernate_timeout = 30s # Maximum IMAP command line length in bytes. Some clients generate very long # command lines with huge mailboxes, so you may need to raise this if you get # "Too long argument" or "IMAP command line too large" errors often. #imap_max_line_length = 65536 # Maximum number of IMAP connections allowed for a user from each IP address. # NOTE: The username is compared case-sensitively. mail_max_userip_connections = 20 # Space separated list of plugins to load (default is global mail_plugins). mail_plugins = acl quota imap_quota mail_plugins = $mail_plugins zlib imap_zlib quota_clone virtual #mail_plugin_dir = /usr/lib/dovecot/imap # IMAP logout format string: # %i - total number of bytes read from client # %o - total number of bytes sent to client # %{fetch_hdr_count} - Number of mails with mail header data sent to client # %{fetch_hdr_bytes} - Number of bytes with mail header data sent to client # %{fetch_body_count} - Number of mails with mail body data sent to client # %{fetch_body_bytes} - Number of bytes with mail body data sent to client # %{deleted} - Number of mails where client added \Deleted flag # %{expunged} - Number of mails that client expunged, which does not # include automatically expunged mails # %{autoexpunged} - Number of mails that were automatically expunged after # client disconnected # %{trashed} - Number of mails that client copied/moved to the # special_use=\Trash mailbox. # %{appended} - Number of mails saved during the session imap_logout_format = in=%i out=%o deleted=%{deleted} expunged=%{expunged} trashed=%{trashed} hdr_count=%{fetch_hdr_count} # Override the IMAP CAPABILITY response. If the value begins with '+', # add the given capabilities on top of the defaults (e.g. +XFOO XBAR). imap_capability = +NAMESPACE # How many seconds to wait between "OK Still here" notifications when # client is IDLEing. imap_idle_notify_interval = 24 min # ID field names and values to send to clients. Using * as the value makes # Dovecot use the default value. The following fields have default values # currently: name, version, os, os-version, support-url, support-email. #imap_id_send = # ID fields sent by client to log. * means everything. #imap_id_log = # Workarounds for various client bugs: # delay-newmail: # Send EXISTS/RECENT new mail notifications only when replying to NOOP # and CHECK commands. Some clients ignore them otherwise, for example OSX # Mail (