One request we often hear from users is the desire to be able to check the status of email servers. Our backend team has been hard at work, and we are happy to announce we now have support for SMTP monitoring! We are rolling out this new feature, and are looking for customers interested in helping up beta test this new monitor. If you run an email server, and would like to check it out, please get in touch with us at email@example.com with "SMTP Beta" in the subject line.
How To Add an SMTP Monitor
Once your account has been setup to support the STMP monitor, it will automatically appear as an option when you click on the Add Host button. You will see it on the list as SMTP(S) MONITOR:
Clicking that menu option will pop up a new creation dialog:
There are a number of options available depending on how your SMTP server is configured. The first options are for including your server address and port. If your server supports secure connections you will want to select the SSL/TLS option. You can also provide vigil-specific authentication if your server requires it for the monitor to connect. We highly recommend setting up a specific Vigil monitoring account for this purpose with a unique username/password combination.
You can use the NAME field to spefify a friendly name you would like to give this monitor so you recognize it on the dashboard and in notifications and reports. The NOTIFICATION SENSITIVITY can be used to adjust when we send out alerts.
We support two methods of checking: VRFY and NOOP.
VRFY Command Option
The VRFY command is a part of the SMTP protocol, and you can read more about it here. This command sends an email address to the server, and the server will respond with a status code indicating whether that account exists on the system. When you select the VRFY SMTP COMMAND option, you will need to provide an email address. This will cause our monitors to issue a command VRFY <email> to your server on the normal monitoring schedule. You can use the Advanced VRFY tab to adjust which status codes are considered good responses:
It is important to note that some administrators consider the VRFY command to be insecure, and it is either disabled, or always returns a positive response. If the command still responds, you can still use it to verify the server is online and responding the external requests. If your server doesn't support the VRFY command at all you can use the second option: NOOP.
NOOP Command Option
The NOOP command is spelled out in the SMTP RFC and you can read more about it here. This command sends just the NOOP string to the server, which responds with an OK. If your server doesn't support the VRFY command, you can use the NOOP as a fallback option. This will verify that your server has connectivity to the internet, and is processing at least minimal requests.
For NOOP, you do not need to provide a recipient email.
Plans and Pricing
When we roll out SMTP monitoring, it will be available automatically for all users at the Business Plan level as a new monitoring option. There will be no additional charge over the regular monthly or annual charge for your plan. If you are not currently on the Business plan, you can upgrade at any time. You can view all our plan options here.