Docker-Postal

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About

This is a fork of the tiredofit/docker-postal repository that is updated to use the latest version of Postal and fix some bugs.

Docker-Postal is a Dockerfile to build a Postal SMTP server for sending and receiving SMTP / HTTP API email.

• Contains Fail2Ban for blocking repeat authentication offenders

Prerequisites

• Required MariaDB Server

Installation

Use the pre-built package

Prebuilt images are available on Docker Hub at siebsie23/docker-postal and are built daily.

Available tags:

Image tag	Description
main	Postal image built on the 'main' branch containing the latest and in-development features (Stuff will break, use at your own risk!)
latest	Latest postal v3 release
*.*.*	Postal image built on a release tag. To view all available images visit siebsie23/docker-postal/tags

Build from Source

Clone this repository and build the image with make build POSTAL_VERSION="version" version being a valid postal branch or tag.

Configuration

Quick Start

• The quickest way to get started is using docker-compose. See the examples folder for a working docker-compose.yml that can be modified for development or production use.

• Set various environment variables to understand the capabilities of this image.

• Map persistent storage for access to configuration and data files for backup.

Persistent Storage

The following directories are used for configuration and can be mapped for persistent storage.

Directory	Description
/config/	Auto generated Postal Config and Signing Key resides here
/logs/	Logfiles
/assets/custom	Optional Use this to drop files overop of the Postal sourcode for cherry picked overrides of files

Environment Variables

Base Images used

This image relies on an Alpine Linux base image that relies on an init system for added capabilities. Outgoing SMTP capabilities are handlded via msmtp. Individual container performance monitoring is performed by zabbix-agent. Additional tools include: bash,curl,less,logrotate, nano,vim.

Be sure to view the following repositories to understand all the customizable options:

Image	Description
OS Base	Customized Image based on Alpine Linux

Admin Accounts

Parameter	Description	Default
ADMIN_EMAIL	Email address of admin	postal@example.com
ADMIN_FNAME	Name of Admin First Name	Postal
ADMIN_LNAME	Name of Admin Last Name	Admin
ADMIN_PASS	Password of Admin user	PostalMailServer

Application Settings

Parameter	Description	Default
MAXIMUM_DELIVERY_ATTEMPTS	Maximum Delivery Attempts before failing	18
MAXIMUM_HOLD_EXPIRY_DAYS	Maximum Holding days before expiring	7
SUPPRESSION_LIST_AUTOMATIC_REMOVAL_DAYS	Suppression List expiry in days	30

DNS Settings

Parameter	Description	Default
DNS_HELO_HOSTNAME	HELO Domain Name Mail Server	postal.example.com
DNS_MX	MX Record Hostnames - Seperate multiple with commas
DNS_SPF_INCLUDE	SPF Hostname	spf.$DNS_HELO_HOSTNAME
DNS_RETURN_PATH_DOMAIN	Return path Hostname	rp.$DNS_HELO_HOSTNAME
DNS_ROUTE_DOMAIN	Routing Domain	routes.$DNS_HELO_HOSTNAME
DNS_TRACK_DOMAIN	Tracking Domain	track.$DNS_HELO_HOSTNAME
DNS_DKIM_IDENTIFIER	DKIM Identifier	postal
DNS_DOMAIN_VERIFY_PREFIX	Domain verification prefix	postal-verification
DNS_RETURN_PATH_PREFIX	Custom Return Path Prefix	psrp

Security Settings

Parameter	Description	Default
ENABLE_FAIL2BAN	Block hsots that repeatedly fail authentication	TRUE
FAIL2BAN_LOG_FILE	Log Location for Fail2ban	/logs/fail2ban/fail2ban.log
FAIL2BAN_TIME_FIND	Track failures for this time period	10m
FAIL2BAN_TIME_BAN	Time to ban repeat offenders	10m
FAIL2BAN_MAX_RETRY	Ban after how many tries during time period	5

Performance Settings

Parameter	Description	Default
WORKERS_THREADS	Amount of Threads per worker.	2
WEB_MAX_THREADS	Maximum amount of webserver threads	5

Logging Settings

Parameter	Description	Default
LOG_CONSOLE	Log to Stdout Console true or false	true
LOG_PATH	Log Location	/logs/
LOG_SIZE_MAX	Maximum Log Size in KB	9999

Database Settings

Parameter	Description	Default
DB_HOST	Hostname of MariaDB Container e.g. postal-db
DB_NAME	Name of MariaDB Database e.g. postal
DB_USER	Database Username e.g. postal
DB_PASS	Password for Above User e.g. password
DB_PORT	MariaDB Server Port	3306
DB_ROOT_PASS	Needed for first boot - Assigns privileges to $DB_USER. This is your MariaDB Root Pass

Anti Spam Settings

Parameter	Description	Default
ENABLE_SPAMASSASSIN	Enable Spamassassin true or false	false
SPAMASSASSIN_HOST	Hostname of Spamassassin daemon
SPAMASSASSIN_PORT	TCP Port of spamassassin daemon	737

Parameter	Description	Default
ENABLE_RSPAMD	Enable RSpamD checking true or false	false
RSPAMD_FLAGS	Flags to pass to rspamd daemon	null
RSPAMD_HOST	Hostname of rspamd daemon
RSPAMD_PASS	RSpamd controller password	null
RSPAMD_PORT	TCP Port of rspamd daemon	11334
RSPAMD_SSL	Use SSL for connecting to rspamd	FALSE

Parameter	Description	Default
SPAM_THRESHOLD	Amount to classify as Spam	5
SPAM_FAILURE_THRESHOLD	Amount to fail as Spam	20

Anti Virus Settings

Parameter	Description	Default
ENABLE_CLAMAV	Enable ClamAV true or false	false
CLAMAV_HOST	Hostname of Clamd Server
CLAMAV_PORT	TCP Port of Clamd Server	3310

SMTP Settings

Client

Parameter	Description	Default
SMTP_CLIENT_OPEN_TIMEOUT	Timeout for an Open Connection in seconds	30
SMTP_CLIENT_READ_TIMEOUT	Timeout for Reading Data in seconds	30

Server

Parameter	Description	Default
SMTP_SERVER_HOSTNAME	SMTP Server hostname	$DNS_HELO_HOSTNAME
SMTP_SERVER_ENABLE_TLS	Enable TLS	false
SMTP_SERVER_LOG_CONNECTIONS	Log SMTP Connections	false
SMTP_SERVER_MAX_MESSAGE_SIZE	Max message size in Megabytes	50
SMTP_SERVER_PORT	Listening Port for Postal Main SMTP Server	25
SMTP_SERVER_PROXY_PROTOCOL	Utilize Proxy Protocol	false
SMTP_SERVER_TLS_SSL_VERSION	SSL Versions	SSLv23
SMTP_SERVER_TLS_CERT	TLS Cert Location (Will authgenerate if not exist)	/certs/cert.pem
SMTP_SERVER_TLS_CIPHERS	TLS Ciphers to use
SMTP_SERVER_TLS_KEY	TLS Key Location (Will autogenerate if not exist)	/certs/key.pem

Management System

Parameter	Description	Default
SMTP_FROM_ADDRESS	From Address for Postam Management System	postal@yourdomain.com
SMTP_FROM_NAME	From Name for Postal Management System	Postal
SMTP_HOST	SMTP Server to be used to send messages from Postal Management System to users	127.0.0.1
SMTP_PORT	SMTP Port to be used to send messages from Postal Management System to Users	25
SMTP_USER	Username to authenticate to SMTP Server
SMTP_PASS	Password to authenticate to SMTP Server

Other Settings

Parameter	Description	Default
CONFIG_FILE	Configuration File	postal.yml
CONFIG_PATH	Configuration Path	/config/
FAST_SERVER_BIND_IP	Bind IP for the Web Interface	0.0.0.0
FAST_SERVER_BIND_PORT_TLS	Bind Port for the TLS Tracking Service	8443
FAST_SERVER_BIND_PORT	Bind Port for the Tracking Server	8080
SETUP_TYPE	Choose AUTO or MANUAL Setup type - Auto uses these environment variables	AUTO
SIGNING_KEY_FILE	Signing Key File	signing.key
SIGNING_KEY_SIZE	Signing Key Size	1024
WEB_BIND_ADDRESS	Bind IP for the Web Interface	0.0.0.0
WEB_PORT	Bind Port for the Web Interface	5000
WEB_HOSTNAME	Hostname for Web Interface	postal.example.com
WEB_PROTOCOL	Protocol for Web Interface http or https	http
WORKER_HEALTH_SERVER_BIND_ADDRESS	Bind IP for the worker health server	0.0.0.0
WORKER_HEALTH_SERVER_PORT	Bind Port for the worker health server	9090

Networking

Port	Description
25	SMTP
80	Web Interface
8080	Fast Server /Tracking
8443	Fast Server / Tracking
5000	Puma`

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Maintenance

Shell Access

For debugging and maintenance purposes you may want access the containers shell.

bash docker exec -it (whatever your container name is) bash

Support

Bugfixes

• Please, submit a Bug Report if something isn't working as expected. I'll do my best to issue a fix in short order.

License

MIT. See LICENSE for more details.

References

• https://github.com/tiredofit/docker-postal
• https://github.com/postalserver/postal