Postfix relay running in Kubernetes
This repository has an example of a postfix relay running in Kubernetes using a helm chart.
Build Docker image
You can build the Docker image locally
docker build -t eldada-docker-examples.bintray.io/postfix-relay:0.3 Docker/
Run locally with Docker
Run the postfix relay locally for testing
# Need to set SMTP connection details
export SMTP="[smtp.mailgun.org]:587"
export USERNAME=<your smtp username>
export PASSWORD=<your smtp password>
# Set list of allowed networks
export TX_SMTP_RELAY_NETWORKS='10.0.0.0/8,127.0.0.0/8,172.17.0.0/16,192.0.0.0/8'
docker run --rm -d --name postfix-relay -p 2525:25 \
-e TX_SMTP_RELAY_HOST="${SMTP}" \
-e TX_SMTP_RELAY_MYHOSTNAME=my.local \
-e TX_SMTP_RELAY_USERNAME=${USERNAME} \
-e TX_SMTP_RELAY_PASSWORD=${PASSWORD} \
-e TX_SMTP_RELAY_NETWORKS=${TX_SMTP_RELAY_NETWORKS} \
eldada-docker-examples.bintray.io/postfix-relay:0.3
Test sending mail
# Run in your host's terminal
# Note the commands and responses from server
telnet localhost 2525
220 tx-smtp-relay.yourhost.com ESMTP Postfix
helo localhost
250 tx-smtp-relay.yourhost.com
mail from: noreply@yourhost.com
250 2.1.0 Ok
rcpt to: you@your.co
250 2.1.5 Ok
data
354 End data with <CR><LF>.<CR><LF>
Subject: Subject here...
The true story of swans singing Pink Floyed.
.
250 2.0.0 Ok: queued as 982FF53C
quit
221 2.0.0 Bye
Connection closed by foreign host
Check the inbox of you@your.co
and see you got the email.
Deploy Helm Chart
The Helm Chart in helm/postfix directory can be used to deploy the postfix-relay into your Kubernetes cluster.
The Chart will deploy 2 pods (for high availability), load balanced with a service, exposing port 25.
# Need to set SMTP connection details
export SMTP="[smtp.mailgun.org]:587"
export USERNAME=<your smtp username>
export PASSWORD=<your smtp password>
helm upgrade --install postfix-relay \
--set smtp.relayHost=${SMTP} \
--set smtp.relayMyhostname=my.local \
--set smtp.relayUsername=${USERNAME} \
--set smtp.relayPassword=${PASSWORD} \
helm/postfix
Thanks
This work is based on examples from https://github.com/applariat/kubernetes-postfix-relay-host