Deliverability problems build slowly and show up late. By the time mail is visibly missing, the cause is days old. Monitoring moves the moment you find out from the symptom to the cause.
What to watch
| Signal | Why it matters | Related entry |
|---|---|---|
| Bounce rate | One of the two numbers AWS reviews you on | Bounce rate |
| Complaint rate | The other number, with a much smaller margin | Complaint rate |
| Send volume | A spike can mean a leaked key or a runaway job, and a silence can mean a broken application | Sending limits |
| Authentication records | DNS changes quietly break SPF, DKIM and DMARC | DNS monitoring |
| Suppression list growth | A rising count says your list is going bad | Suppression list |
| Engagement | Falling opens and clicks often come before reputation drops | Sender reputation |
| Account status | AWS changes your enforcement status | Account review |
Monitoring versus dashboards
A dashboard shows you the data when you look. Monitoring comes to you. The difference is the difference between finding a bounce spike three hours after it started and being told in five minutes. Good monitoring combines both: thresholds for rates, baselines for anomalies, and a summary for the slow drift neither catches.
Doing it on Amazon SES
SES supplies the raw material: events, metrics and a few APIs. Building on it yourself means CloudWatch alarms, an SNS pipeline, somewhere to keep the events and a way to search them. Virtual Deliverability Manager adds dashboards but no alerting. A monitoring tool takes the whole job off your hands.
Starting simple
If you do nothing else, alert on the bounce rate and the complaint rate at half the AWS review limits, watch your daily send volume for jumps, and check your authentication records on a schedule.
Common questions
How is it different from an inbox placement test?
Placement tests send sample mail to test mailboxes and report where it lands. Monitoring watches your real traffic and its signals continuously. They answer different questions and work well together.
How often should I check?
You should not have to. Set alerts so the tool tells you when something changes, and use a periodic summary to catch slow trends.