How to Create Devices and Targets

How it Works

During SMTP monitoring, the agents monitor the SMTP server by connecting to the specified mail server and performing an SMTP handshake. If a remote server does not respond to a handshake or is unavailable, an error condition will be triggered.  If you have alerts configured, you will receive an alert.

Creating a Target

Hostname / Port

Enter the SMTP server address and port number. This could be the URL or the IP address.

Time Validation Threshold (in seconds)

Enter the number of seconds the system should wait for a response from the target resource before returning an error. If this is left blank the default timeout is 120 seconds.

Encryption

When enabled – SMTP over SSL/TLS will be requested:

  • YES explicit – connects to the server and explicitly requests TLS encryption to be enabled by sending the STARTTLS command to the server. Default port is Port 587.
  • YES implicit – TLS encryption is switched on implicitly for receiving mail over an encrypted connection. Default port is Port 465.
  • None – ncryption is not used. Username/password can be sent encrypted (e.g., by using base64). Default port is Port 25.
  • Auto – TLS encryption will only be used if Dotcom-Monitor client considers it necessary and if the server informs the client that it supports TLS encryption.

If you select encrypted connection, please make sure there is the correct port number in the Hostname / Port fields. If the port number is not specified, a default port will be used instead.

Login to Server

When disabled –Dotcom-Monitor® connects to the destination address and port and checks for a successful connection.

When enabled – the authentication procedure will perform the following steps using the credentials supplied in the Login Information section:

User Name: Enter a username for SMTP authentication

Password:  Enter a password for SMTP authentication

The authentication will be attempted using the following methods:

  • CRAM_MD5
  • Login
  • Plain
  • Simple
  • SSL/TLS

If none of the methods have succeeded unencrypted, the socket is switched to SSL and repeats each method until a positive response is received (according to RFC 5034 on authentication mechanisms).

DNS Options

The DNS Options feature allows users to choose how domain name server (DNS) requests are conducted during a monitoring task.

To specify the mode of resolving hostnames, in the DNS Resolve Mode section, select one of the available modes. For more details on the feature configuration, see DNS Mode Options.

The Custom DNS Hosts section allows to set up the mapping of IP addresses to hostnames. IPv6 and IPv4 DNS resolution is supported.

To specify the mapping, enter the IP address and the hostname in the corresponding fields.

Examples:

192.168.107.246   example.com user.example.com userauth.example.com tools.example.com
192.168.107.246   example.com
192.168.107.246   user.example.com
192.168.107.246   userauth.example.com

See also: DNS Mode Options.


SMTP servers are allowed only to accept connections from a specific list of hosts. So, in order to proceed with monitoring without obstacles, Dotcom-Monitor monitoring agents should be white-listed in a firewall.