# Mailserver options ## `mailserver` `````{option} mailserver.debug Whether to enable verbose logging for mailserver related services. This intended be used for development purposes only, you probably don't want to enable this unless you're hacking on nixos-mailserver. - type: ```boolean``` - default: ```False``` ````` `````{option} mailserver.domains The domains that this mail server serves. - type: ```list of string``` - default: ```[]``` - example: ```['example.com']``` ````` `````{option} mailserver.enable Whether to enable nixos-mailserver. - type: ```boolean``` - default: ```False``` - example: ```True``` ````` `````{option} mailserver.enableImap Whether to enable IMAP with STARTTLS on port 143. - type: ```boolean``` - default: ```True``` ````` `````{option} mailserver.enableImapSsl Whether to enable IMAP with TLS in wrapper-mode on port 993. - type: ```boolean``` - default: ```True``` ````` `````{option} mailserver.enableManageSieve Whether to enable ManageSieve, setting this option to true will open port 4190 in the firewall. The ManageSieve protocol allows users to manage their Sieve scripts on a remote server with a supported client, including Thunderbird. - type: ```boolean``` - default: ```False``` ````` `````{option} mailserver.enablePop3 Whether to enable POP3 with STARTTLS on port on port 110. - type: ```boolean``` - default: ```False``` ````` `````{option} mailserver.enablePop3Ssl Whether to enable POP3 with TLS in wrapper-mode on port 995. - type: ```boolean``` - default: ```False``` ````` `````{option} mailserver.enableSubmission Whether to enable SMTP with STARTTLS on port 587. - type: ```boolean``` - default: ```True``` ````` `````{option} mailserver.enableSubmissionSsl Whether to enable SMTP with TLS in wrapper-mode on port 465. - type: ```boolean``` - default: ```True``` ````` `````{option} mailserver.extraVirtualAliases Virtual Aliases. A virtual alias `"info@example.com" = "user1@example.com"` means that all mail to `info@example.com` is forwarded to `user1@example.com`. Note that it is expected that `postmaster@example.com` and `abuse@example.com` is forwarded to some valid email address. (Alternatively you can create login accounts for `postmaster` and (or) `abuse`). Furthermore, it also allows the user `user1@example.com` to send emails as `info@example.com`. It's also possible to create an alias for multiple accounts. In this example all mails for `multi@example.com` will be forwarded to both `user1@example.com` and `user2@example.com`. - type: ```attribute set of ((Login Account) or non-empty (list of (Login Account)))``` - default: ```{}``` - example: ```{'abuse@example.com': 'user1@example.com', 'info@example.com': 'user1@example.com', 'multi@example.com': ['user1@example.com', 'user2@example.com'], 'postmaster@example.com': 'user1@example.com'}``` ````` `````{option} mailserver.forwards To forward mails to an external address. For instance, the value {`"user@example.com" = "user@elsewhere.com";}` means that mails to `user@example.com` are forwarded to `user@elsewhere.com`. The difference with the {option}`mailserver.extraVirtualAliases` option is that `user@elsewhere.com` can't send mail as `user@example.com`. Also, this option allows to forward mails to external addresses. - type: ```attribute set of ((list of string) or string)``` - default: ```{}``` - example: ```{'user@example.com': 'user@elsewhere.com'}``` ````` `````{option} mailserver.fqdn The fully qualified domain name of the mail server. - type: ```string``` - example: ```mx.example.com``` ````` `````{option} mailserver.hierarchySeparator The hierarchy separator for mailboxes used by dovecot for the namespace 'inbox'. Dovecot defaults to "." but recommends "/". This affects how mailboxes appear to mail clients and sieve scripts. For instance when using "." then in a sieve script "example.com" would refer to the mailbox "com" in the parent mailbox "example". This does not determine the way your mails are stored on disk. See https://wiki.dovecot.org/Namespaces for details. - type: ```string``` - default: ```.``` ````` `````{option} mailserver.indexDir Folder to store search indices. If null, indices are stored along with email, which could not necessarily be desirable, especially when {option}`mailserver.fullTextSearch.enable` is `true` since indices it creates are voluminous and do not need to be backed up. Be careful when changing this option value since all indices would be recreated at the new location (and clients would need to resynchronize). Note the some variables can be used in the file path. See https://doc.dovecot.org/configuration_manual/mail_location/#variables for details. - type: ```null or string``` - default: ```None``` - example: ```/var/lib/dovecot/indices``` ````` `````{option} mailserver.keyFile Scheme 1) Location of the key file - type: ```path``` - example: ```/root/mail-server.key``` ````` `````{option} mailserver.lmtpSaveToDetailMailbox If an email address is delimited by a "+", should it be filed into a mailbox matching the string after the "+"? For example, user1+test@example.com would be filed into the mailbox "test". - type: ```one of "yes", "no"``` - default: ```yes``` ````` `````{option} mailserver.localDnsResolver Runs a local DNS resolver (kresd) as recommended when running rspamd. This prevents your log file from filling up with rspamd_monitored_dns_mon entries. - type: ```boolean``` - default: ```True``` ````` `````{option} mailserver.mailDirectory Where to store the mail. - type: ```path``` - default: ```/var/vmail``` ````` `````{option} mailserver.mailboxes The mailboxes for dovecot. Depending on the mail client used it might be necessary to change some mailbox's name. - type: ```unspecified value``` - default: ```{'Drafts': {'auto': 'subscribe', 'specialUse': 'Drafts'}, 'Junk': {'auto': 'subscribe', 'specialUse': 'Junk'}, 'Sent': {'auto': 'subscribe', 'specialUse': 'Sent'}, 'Trash': {'auto': 'no', 'specialUse': 'Trash'}}``` ````` `````{option} mailserver.maxConnectionsPerUser Maximum number of IMAP/POP3 connections allowed for a user from each IP address. E.g. a value of 50 allows for 50 IMAP and 50 POP3 connections at the same time for a single user. - type: ```signed integer``` - default: ```100``` ````` `````{option} mailserver.messageSizeLimit Message size limit enforced by Postfix. - type: ```signed integer``` - default: ```20971520``` - example: ```52428800``` ````` `````{option} mailserver.openFirewall Automatically open ports in the firewall. - type: ```boolean``` - default: ```True``` ````` `````{option} mailserver.policydSPFExtraConfig Extra configuration options for policyd-spf. This can be use to among other things skip spf checking for some IP addresses. - type: ```strings concatenated with "\n"``` - default: `""` - example: ``` skip_addresses = 127.0.0.0/8,::ffff:127.0.0.0/104,::1 ``` ````` `````{option} mailserver.rebootAfterKernelUpgrade.enable Whether to enable automatic reboot after kernel upgrades. This is to be used in conjunction with `system.autoUpgrade.enable = true;` - type: ```boolean``` - default: ```False``` - example: ```True``` ````` `````{option} mailserver.rebootAfterKernelUpgrade.method Whether to issue a full "reboot" or just a "systemctl kexec"-only reboot. It is recommended to use the default value because the quicker kexec reboot has a number of problems. Also if your server is running in a virtual machine the regular reboot will already be very quick. - type: ```one of "reboot", "systemctl kexec"``` - default: ```reboot``` ````` `````{option} mailserver.recipientDelimiter Configure the recipient delimiter. - type: ```string``` - default: ```+``` ````` `````{option} mailserver.rejectRecipients Reject emails addressed to these local addresses from unauthorized senders. Use if a spammer has found email addresses in a catchall domain but you do not want to disable the catchall. - type: ```list of string``` - default: ```[]``` - example: ```['sales@example.com', 'info@example.com']``` ````` `````{option} mailserver.rejectSender Reject emails from these addresses from unauthorized senders. Use if a spammer is using the same domain or the same sender over and over. - type: ```list of string``` - default: ```[]``` - example: ```['@example.com', 'spammer@example.net']``` ````` `````{option} mailserver.rewriteMessageId Rewrites the Message-ID's hostname-part of outgoing emails to the FQDN. Please be aware that this may cause problems with some mail clients relying on the original Message-ID. - type: ```boolean``` - default: ```False``` ````` `````{option} mailserver.sendingFqdn The fully qualified domain name of the mail server used to identify with remote servers. If this server's IP serves purposes other than a mail server, it may be desirable for the server to have a name other than that to which the user will connect. For example, the user might connect to mx.example.com, but the server's IP has reverse DNS that resolves to myserver.example.com; in this scenario, some mail servers may reject or penalize the message. This setting allows the server to identify as myserver.example.com when forwarding mail, independently of {option}`mailserver.fqdn` (which, for SSL reasons, should generally be the name to which the user connects). Set this to the name to which the sending IP's reverse DNS resolves. - type: ```string``` - default: {option}`mailserver.fqdn` - example: ```myserver.example.com``` ````` `````{option} mailserver.sieveDirectory Where to store the sieve scripts. - type: ```path``` - default: ```/var/sieve``` ````` `````{option} mailserver.useFsLayout Sets whether dovecot should organize mail in subdirectories: - /var/vmail/example.com/user/.folder.subfolder/ (default layout) - /var/vmail/example.com/user/folder/subfolder/ (FS layout) See https://wiki2.dovecot.org/MailboxFormat/Maildir for details. - type: ```boolean``` - default: ```False``` ````` `````{option} mailserver.virusScanning Whether to activate virus scanning. Note that virus scanning is _very_ expensive memory wise. - type: ```boolean``` - default: ```False``` ````` `````{option} mailserver.vmailGroupName The user name and group name of the user that owns the directory where all the mail is stored. - type: ```string``` - default: ```virtualMail``` ````` `````{option} mailserver.vmailUID The unix UID of the virtual mail user. Be mindful that if this is changed, you will need to manually adjust the permissions of `mailDirectory`. - type: ```signed integer``` - default: ```5000``` ````` `````{option} mailserver.vmailUserName The user name and group name of the user that owns the directory where all the mail is stored. - type: ```string``` - default: ```virtualMail``` ````` ## `mailserver.loginAccounts` `````{option} mailserver.loginAccounts The login account of the domain. Every account is mapped to a unix user, e.g. `user1@example.com`. To generate the passwords use `mkpasswd` as follows ``` nix-shell -p mkpasswd --run 'mkpasswd -sm bcrypt' ``` - type: ```attribute set of (submodule)``` - default: ```{}``` - example: ```{'user1': {'hashedPassword': '$6$evQJs5CFQyPAW09S$Cn99Y8.QjZ2IBnSu4qf1vBxDRWkaIZWOtmu1Ddsm3.H3CFpeVc0JU4llIq8HQXgeatvYhh5O33eWG3TSpjzu6/'}, 'user2': {'hashedPassword': '$6$oE0ZNv2n7Vk9gOf$9xcZWCCLGdMflIfuA0vR1Q1Xblw6RZqPrP94mEit2/81/7AKj2bqUai5yPyWE.QYPyv6wLMHZvjw3Rlg7yTCD/'}}``` ````` `````{option} mailserver.loginAccounts..aliases A list of aliases of this login account. Note: Use list entries like "@example.com" to create a catchAll that allows sending from all email addresses in these domain. - type: ```list of string``` - default: ```[]``` - example: ```['abuse@example.com', 'postmaster@example.com']``` ````` `````{option} mailserver.loginAccounts..catchAll For which domains should this account act as a catch all? Note: Does not allow sending from all addresses of these domains. - type: ```list of value "example.com" (singular enum)``` - default: ```[]``` - example: ```['example.com', 'example2.com']``` ````` `````{option} mailserver.loginAccounts..hashedPassword The user's hashed password. Use `mkpasswd` as follows ``` nix-shell -p mkpasswd --run 'mkpasswd -sm bcrypt' ``` Warning: this is stored in plaintext in the Nix store! Use {option}`mailserver.loginAccounts..hashedPasswordFile` instead. - type: ```null or string``` - default: ```None``` - example: ```$6$evQJs5CFQyPAW09S$Cn99Y8.QjZ2IBnSu4qf1vBxDRWkaIZWOtmu1Ddsm3.H3CFpeVc0JU4llIq8HQXgeatvYhh5O33eWG3TSpjzu6/``` ````` `````{option} mailserver.loginAccounts..hashedPasswordFile A file containing the user's hashed password. Use `mkpasswd` as follows ``` nix-shell -p mkpasswd --run 'mkpasswd -sm bcrypt' ``` - type: ```null or path``` - default: ```None``` - example: ```/run/keys/user1-passwordhash``` ````` `````{option} mailserver.loginAccounts..name Username - type: ```string``` - example: ```user1@example.com``` ````` `````{option} mailserver.loginAccounts..quota Per user quota rules. Accepted sizes are `xx k/M/G/T` with the obvious meaning. Leave blank for the standard quota `100G`. - type: ```null or string``` - default: ```None``` - example: ```2G``` ````` `````{option} mailserver.loginAccounts..sendOnly Specifies if the account should be a send-only account. Emails sent to send-only accounts will be rejected from unauthorized senders with the `sendOnlyRejectMessage` stating the reason. - type: ```boolean``` - default: ```False``` ````` `````{option} mailserver.loginAccounts..sendOnlyRejectMessage The message that will be returned to the sender when an email is sent to a send-only account. Only used if the account is marked as send-only. - type: ```string``` - default: ```This account cannot receive emails.``` ````` `````{option} mailserver.loginAccounts..sieveScript Per-user sieve script. - type: ```null or strings concatenated with "\n"``` - default: ```None``` - example: ``` require ["fileinto", "mailbox"]; if address :is "from" "gitlab@mg.gitlab.com" { fileinto :create "GitLab"; stop; } # This must be the last rule, it will check if list-id is set, and # file the message into the Lists folder for further investigation elsif header :matches "list-id" "" { fileinto :create "Lists"; stop; } ``` ````` ## `mailserver.certificate` `````{option} mailserver.certificateDirectory Scheme 2) This is the folder where the certificate will be created. The name is hardcoded to "cert-DOMAIN.pem" and "key-DOMAIN.pem" and the certificate is valid for 10 years. - type: ```path``` - default: ```/var/certs``` ````` `````{option} mailserver.certificateDomains Secondary domains and subdomains for which it is necessary to generate a certificate. - type: ```list of string``` - default: ```[]``` - example: ```['imap.example.com', 'pop3.example.com']``` ````` `````{option} mailserver.certificateFile Scheme 1) Location of the certificate - type: ```path``` - example: ```/root/mail-server.crt``` ````` `````{option} mailserver.certificateScheme Certificate Files. There are three options for these. 1) You specify locations and manually copy certificates there. 2) You let the server create new (self signed) certificates on the fly. 3) You let the server create a certificate via `Let's Encrypt`. Note that this implies that a stripped down webserver has to be started. This also implies that the FQDN must be set as an `A` record to point to the IP of the server. In particular port 80 on the server will be opened. For details on how to set up the domain records, see the guide in the readme. - type: ```one of 1, 2, 3``` - default: ```2``` ````` ## `mailserver.dkim` `````{option} mailserver.dkimBodyCanonicalization DKIM canonicalization algorithm for message bodies. See https://datatracker.ietf.org/doc/html/rfc6376/#section-3.4 for details. - type: ```one of "relaxed", "simple"``` - default: ```relaxed``` ````` `````{option} mailserver.dkimHeaderCanonicalization DKIM canonicalization algorithm for message headers. See https://datatracker.ietf.org/doc/html/rfc6376/#section-3.4 for details. - type: ```one of "relaxed", "simple"``` - default: ```relaxed``` ````` `````{option} mailserver.dkimKeyBits How many bits in generated DKIM keys. RFC6376 advises minimum 1024-bit keys. If you have already deployed a key with a different number of bits than specified here, then you should use a different selector ({option}`mailserver.dkimSelector`). In order to get this package to generate a key with the new number of bits, you will either have to change the selector or delete the old key file. - type: ```signed integer``` - default: ```1024``` ````` `````{option} mailserver.dkimKeyDirectory The DKIM directory. - type: ```path``` - default: ```/var/dkim``` ````` `````{option} mailserver.dkimSelector The DKIM selector. - type: ```string``` - default: ```mail``` ````` `````{option} mailserver.dkimSigning Whether to activate dkim signing. - type: ```boolean``` - default: ```True``` ````` ## `mailserver.dmarcReporting` `````{option} mailserver.dmarcReporting.domain The domain from which outgoing DMARC reports are served. - type: ```value "example.com" (singular enum)``` - example: ```example.com``` ````` `````{option} mailserver.dmarcReporting.email The email address used for outgoing DMARC reports. Read-only. - type: ```string``` - default: ```"${localpart}@${domain}"``` ````` `````{option} mailserver.dmarcReporting.enable Whether to send out aggregated, daily DMARC reports in response to incoming mail, when the sender domain defines a DMARC policy including the RUA tag. This is helpful for the mail ecosystem, because it allows third parties to get notified about SPF/DKIM violations originating from their sender domains. See https://rspamd.com/doc/modules/dmarc.html#reporting - type: ```boolean``` - default: ```False``` ````` `````{option} mailserver.dmarcReporting.fromName The sender name for DMARC reports. Defaults to the organization name. - type: ```string``` - default: {option}`mailserver.dmarcReporting.organizationName` ````` `````{option} mailserver.dmarcReporting.localpart The local part of the email address used for outgoing DMARC reports. - type: ```string``` - default: ```dmarc-noreply``` - example: ```dmarc-report``` ````` `````{option} mailserver.dmarcReporting.organizationName The name of your organization used in the `org_name` attribute in DMARC reports. - type: ```string``` - example: ```ACME Corp.``` ````` ## `mailserver.fullTextSearch` `````{option} mailserver.fullTextSearch.autoIndex Enable automatic indexing of messages as they are received or modified. - type: ```boolean``` - default: ```True``` ````` `````{option} mailserver.fullTextSearch.autoIndexExclude Mailboxes to exclude from automatic indexing. - type: ```list of string``` - default: ```[]``` - example: ```['\\Trash', 'SomeFolder', 'Other/*']``` ````` `````{option} mailserver.fullTextSearch.enable Whether to enable Full text search indexing with xapian. This has significant performance and disk space cost.. - type: ```boolean``` - default: ```False``` - example: ```True``` ````` `````{option} mailserver.fullTextSearch.enforced Fail searches when no index is available. If set to `body`, then only body searches (as opposed to header) are affected. If set to `no`, searches may fall back to a very slow brute force search. - type: ```one of "yes", "no", "body"``` - default: ```no``` ````` `````{option} mailserver.fullTextSearch.indexAttachments Also index text-only attachements. Binary attachements are never indexed. - type: ```boolean``` - default: ```False``` ````` `````{option} mailserver.fullTextSearch.maintenance.enable Regularly optmize indices, as recommended by upstream. - type: ```boolean``` - default: ```True``` ````` `````{option} mailserver.fullTextSearch.maintenance.onCalendar When to run the maintenance job. See systemd.time(7) for more information about the format. - type: ```string``` - default: ```daily``` ````` `````{option} mailserver.fullTextSearch.maintenance.randomizedDelaySec Run the maintenance job not exactly at the time specified with `onCalendar`, but plus or minus this many seconds. - type: ```signed integer``` - default: ```1000``` ````` `````{option} mailserver.fullTextSearch.maxSize Size of the largest n-gram to index. - type: ```signed integer``` - default: ```20``` ````` `````{option} mailserver.fullTextSearch.memoryLimit Memory limit for the indexer process, in MiB. If null, leaves the default (which is rather low), and if 0, no limit. - type: ```null or signed integer``` - default: ```None``` - example: ```2000``` ````` `````{option} mailserver.fullTextSearch.minSize Size of the smallest n-gram to index. - type: ```signed integer``` - default: ```2``` ````` ## `mailserver.redis` `````{option} mailserver.redis.address Address that rspamd should use to contact redis. - type: ```string``` - default: computed from `config.services.redis.servers.rspamd.bind` ````` `````{option} mailserver.redis.password Password that rspamd should use to contact redis, or null if not required. - type: ```null or string``` - default: ```config.services.redis.servers.rspamd.requirePass``` ````` `````{option} mailserver.redis.port Port that rspamd should use to contact redis. - type: ```16 bit unsigned integer; between 0 and 65535 (both inclusive)``` - default: ```config.services.redis.servers.rspamd.port``` ````` ## `mailserver.monitoring` `````{option} mailserver.monitoring.alertAddress The email address to send alerts to. - type: ```string``` ````` `````{option} mailserver.monitoring.config The configuration used for monitoring via monit. Use a mail address that you actively check and set it via 'set alert ...'. - type: ```string``` - default: see [source](https://gitlab.com/simple-nixos-mailserver/nixos-mailserver/-/blob/master/default.nix) ````` `````{option} mailserver.monitoring.enable Whether to enable monitoring via monit. - type: ```boolean``` - default: ```False``` - example: ```True``` ````` ## `mailserver.backup` `````{option} mailserver.backup.cmdPostexec The command to be executed after each backup operation. This is wrapped in a shell script to be called by rsnapshot. - type: ```null or string``` - default: ```None``` ````` `````{option} mailserver.backup.cmdPreexec The command to be executed before each backup operation. This is wrapped in a shell script to be called by rsnapshot. - type: ```null or string``` - default: ```None``` ````` `````{option} mailserver.backup.cronIntervals Periodicity at which intervals should be run by cron. Note that the intervals also have to exist in configuration as retain options. - type: ```attribute set of string``` - default: ```{'daily': '30 3 * * *', 'hourly': ' 0 * * * *', 'weekly': ' 0 5 * * 0'}``` ````` `````{option} mailserver.backup.enable Whether to enable backup via rsnapshot. - type: ```boolean``` - default: ```False``` - example: ```True``` ````` `````{option} mailserver.backup.retain.daily How many daily snapshots are retained. - type: ```signed integer``` - default: ```7``` ````` `````{option} mailserver.backup.retain.hourly How many hourly snapshots are retained. - type: ```signed integer``` - default: ```24``` ````` `````{option} mailserver.backup.retain.weekly How many weekly snapshots are retained. - type: ```signed integer``` - default: ```54``` ````` `````{option} mailserver.backup.snapshotRoot The directory where rsnapshot stores the backup. - type: ```path``` - default: ```/var/rsnapshot``` ````` ## `mailserver.borgbackup` `````{option} mailserver.borgbackup.cmdPostexec The command to be executed after each backup operation. This is called after borg create completed successfully and in the same script that runs `cmdPreexec`, borg init and create. - type: ```null or string``` - default: ```None``` ````` `````{option} mailserver.borgbackup.cmdPreexec The command to be executed before each backup operation. This is called prior to borg init in the same script that runs borg init and create and `cmdPostexec`. - type: ```null or string``` - default: ```None``` - example: ``` export BORG_RSH="ssh -i /path/to/private/key" ``` ````` `````{option} mailserver.borgbackup.compression.auto Leaves it to borg to determine whether an individual file should be compressed. - type: ```boolean``` - default: ```False``` ````` `````{option} mailserver.borgbackup.compression.level Denotes the level of compression used by borg. Most methods accept levels from 0 to 9 but zstd which accepts values from 1 to 22. If null the decision is left up to borg. - type: ```null or signed integer``` - default: ```None``` ````` `````{option} mailserver.borgbackup.compression.method Leaving this unset allows borg to choose. The default for borg 1.1.4 is lz4. - type: ```null or one of "none", "lz4", "zstd", "zlib", "lzma"``` - default: ```None``` ````` `````{option} mailserver.borgbackup.enable Whether to enable backup via borgbackup. - type: ```boolean``` - default: ```False``` - example: ```True``` ````` `````{option} mailserver.borgbackup.encryption.method The backup can be encrypted by choosing any other value than 'none'. When using encryption the password/passphrase must be provided in `passphraseFile`. - type: ```one of "none", "authenticated", "authenticated-blake2", "repokey", "keyfile", "repokey-blake2", "keyfile-blake2"``` - default: ```none``` ````` `````{option} mailserver.borgbackup.encryption.passphraseFile Path to a file containing the encryption password or passphrase. - type: ```null or path``` - default: ```None``` ````` `````{option} mailserver.borgbackup.extraArgumentsForCreate Additional arguments to add to the borg create command line e.g. '--stats'. - type: ```list of string``` - default: ```[]``` ````` `````{option} mailserver.borgbackup.extraArgumentsForInit Additional arguments to add to the borg init command line. - type: ```list of string``` - default: ```['--critical']``` ````` `````{option} mailserver.borgbackup.group The group borg and its launch script is run as. - type: ```string``` - default: ```virtualMail``` ````` `````{option} mailserver.borgbackup.locations The locations that are to be backed up by borg. - type: ```list of path``` - default: ```[ config.mailserver.mailDirectory ]``` ````` `````{option} mailserver.borgbackup.name The name of the individual backups as used by borg. Certain placeholders will be replaced by borg. - type: ```string``` - default: ```{hostname}-{user}-{now}``` ````` `````{option} mailserver.borgbackup.repoLocation The location where borg saves the backups. This can be a local path or a remote location such as user@host:/path/to/repo. It is exported and thus available as an environment variable to {option}`mailserver.borgbackup.cmdPreexec` and {option}`mailserver.borgbackup.cmdPostexec`. - type: ```string``` - default: ```/var/borgbackup``` ````` `````{option} mailserver.borgbackup.startAt When or how often the backup should run. Must be in the format described in systemd.time 7. - type: ```string``` - default: ```hourly``` ````` `````{option} mailserver.borgbackup.user The user borg and its launch script is run as. - type: ```string``` - default: ```virtualMail``` `````