SMTP Pools

SMTP pools let you route outbound email through your own SMTP relay instead of MisarMail's shared sending infrastructure. This is useful when you have an existing arrangement with a provider like Amazon SES, Postfix, Mailgun, or SendGrid, or when you need isolated sending pools for different business units.

The same functionality is available in the dashboard at Settings → SMTP Pools.

List SMTP pools

GET /api/smtp-pools

Returns all configured SMTP pools for the account. Passwords are never included in responses.

[
  {
    "id": "smtp_01hx3k",
    "name": "Amazon SES — us-east-1",
    "host": "email-smtp.us-east-1.amazonaws.com",
    "port": 587,
    "username": "AKIAIOSFODNN7EXAMPLE",
    "encryption": "tls",
    "is_active": true,
    "created_at": "2025-05-01T00:00:00Z"
  }
]

Create SMTP pool

POST /api/smtp-pools
Content-Type: application/json

Common provider settings

curl -X POST /api/smtp-pools \
  -H "Content-Type: application/json" \
  -d '{
    "name": "Amazon SES — us-east-1",
    "host": "email-smtp.us-east-1.amazonaws.com",
    "port": 587,
    "username": "AKIAIOSFODNN7EXAMPLE",
    "password": "your-ses-smtp-password",
    "encryption": "tls"
  }'

const res = await fetch('/api/smtp-pools', {
  method: 'POST',
  credentials: 'include',
  headers: { 'Content-Type': 'application/json' },
  body: JSON.stringify({
    name: 'Amazon SES — us-east-1',
    host: 'email-smtp.us-east-1.amazonaws.com',
    port: 587,
    username: process.env.SES_USERNAME,
    password: process.env.SES_PASSWORD,
    encryption: 'tls',
  }),
});
const pool = await res.json();

Test SMTP connection

POST /api/smtp-pools/:id/test

Sends a test connection to the configured SMTP server. No request body is required.

{
  "success": true,
  "message": "SMTP connection successful",
  "latencyMs": 142
}

On failure:

{
  "success": false,
  "message": "SMTP connection failed",
  "latencyMs": 5000,
  "error": "connect ECONNREFUSED 198.51.100.1:587"
}

Using an SMTP pool for sends

Once a pool is created, reference it by including alias_id in your send request:

curl -X POST https://api.misar.io/mail/v1/send \
  -H "Authorization: Bearer msk_..." \
  -H "Content-Type: application/json" \
  -d '{
    "to": [{ "email": "[email protected]" }],
    "from": { "email": "[email protected]", "name": "Acme" },
    "subject": "Your order is confirmed",
    "html": "<p>Thanks for your order!</p>",
    "alias_id": "smtp_01hx3k"
  }'

If alias_id is omitted, MisarMail uses its default shared sending pool.

Amazon SES setup notes

1. Verify your sending domain in the SES console
2. Request production access if you are out of the SES sandbox
3. Create SMTP credentials in SES → Account dashboard → SMTP settings → Create SMTP credentials
4. Use port 587 with STARTTLS (tls encryption)
5. Ensure your EC2 or VPS security group allows outbound TCP on port 587