Send Grafana email through SMTP with Ackuna

Before you start

You need three things from Ackuna. Each takes a few minutes, except the review in step 2.

1. An Ackuna account. Create one for free; no card is needed.
2. A verified sending domain. Add the domain your app sends from (for example yourdomain.com) under SMTP Relay, Domains in the console and publish the SPF, DKIM and DMARC records it shows you. The console checks them for you. A new sending domain is also reviewed by our team before it can send; that is not instant, and until it is approved the relay answers 452.
3. An SMTP credential for that domain. Under SMTP Relay, Credentials, create one for the verified domain. You get a username (smtp_…) and a password (sc_…). The password is shown once, so paste it into Grafana straight away; if you lose it, rotate the credential.

The From address in Grafana must be on exactly that domain. A credential for yourdomain.com can send as [email protected], but not from a subdomain such as mail.yourdomain.com or from another domain.

The settings

Grafana reads its email settings from the [smtp] section of its configuration file (/etc/grafana/grafana.ini on Linux packages, conf/custom.ini in a standalone install):

[smtp]
enabled = true
host = smtp.ackuna.com:587
user = YOUR_SMTP_USERNAME
password = YOUR_SMTP_PASSWORD
from_address = [email protected]
from_name = Grafana
startTLS_policy = MandatoryStartTLS
skip_verify = false

• host takes the host and the port together. Grafana's docs say to use port 465 for implicit TLS; the relay does not offer that, so use 587.
• startTLS_policy accepts OpportunisticStartTLS, MandatoryStartTLS or NoStartTLS. MandatoryStartTLS makes Grafana refuse to send if the upgrade does not happen, rather than log in unencrypted. The relay always offers STARTTLS, so this is the safe choice.
• If a password ever contains # or ;, Grafana's docs say to wrap it in triple quotes ("""…""").
• from_address must be on your verified domain.

Environment variables instead

Grafana overrides any option with a variable named GF_<SECTION>_<KEY>, in upper case:

GF_SMTP_ENABLED=true
GF_SMTP_HOST=smtp.ackuna.com:587
GF_SMTP_USER=YOUR_SMTP_USERNAME
GF_SMTP_PASSWORD=YOUR_SMTP_PASSWORD
[email protected]
GF_SMTP_FROM_NAME=Grafana
GF_SMTP_STARTTLS_POLICY=MandatoryStartTLS

Restart Grafana after changing the file or the variables.

Send a test email

Create or edit an email contact point: in the left-side menu, open Alerts & IRM, Alerting, Notification configuration, the Contact points tab. Edit the contact point, click Test, then Send test notification. Grafana's docs note that testing a contact point is only available for the Grafana Alertmanager. The message appears under SMTP Relay, Messages in the Ackuna console.

Common errors

Authentication failed (535)

The username or password is wrong, the credential was revoked, or its domain is no longer active. Copy both values again from the console, with no spaces around them. If you no longer have the password, rotate the credential and paste the new one.

TLS handshake error, "wrong version number" or a connection that hangs

The app is trying SSL/TLS on connect, which the relay does not offer. Use port 587 with STARTTLS: the connection starts in plain text and is upgraded before the login. If the connection times out instead, check that your host or firewall allows outgoing connections to port 587; some cloud providers block it on new servers until you ask them to lift the block.

Sender rejected (550)

The From address is not on the domain the credential was created for. Set the From address in Grafana to an address on that exact domain. The same code is used for a recipient on your suppression list, because an earlier message to them bounced or was marked as spam.

Temporarily rejected (452)

Either you have reached your daily or monthly limit, or the sending domain is still waiting for review. Both are temporary: a mail server retries later, and the console shows your usage. A message with more than 10 recipients is also refused with 452, and one over 10 MB with 552.

Mail that is accepted but lands in spam usually points at DNS, not SMTP. Run the Email DNS check on your domain, or the SPF, DKIM and DMARC checkers one by one.

Limits

• The Free plan includes 3,000 relay emails a month and 100 a day, 1 SMTP credential and 1 sending domain. Paid plans and their limits are on the pricing page.
• New accounts start on lower limits until Ackuna has reviewed them: at most 20 Agent Mail, 200 SMTP relay and 500 newsletter emails a day, whatever the plan allows. After the review the plan limits above apply.
• Each new sending domain is reviewed before it can send.
• One message can have up to 10 recipients and be up to 10 MB.
• While we deploy an update, port 587 stays open and the relay holds the mail it accepts, then sends it when the update is done. A login it cannot check during that time gets a temporary 451; a retry goes through once the update is done.