Documentation

OpenSMTPD Input Plugin

This plugin gathers statistics from OpenSMTPD using the smtpctl binary.

The smtpctl binary must be present on the system and executable by Telegraf. The plugin supports using sudo for execution.

Introduced in: Telegraf v1.5.0 Tags: server, network OS support: all

Global configuration options

In addition to the plugin-specific configuration settings, plugins support additional global and plugin configuration settings. These settings are used to modify metrics, tags, and field or create aliases and configure ordering, etc. See the CONFIGURATION.md for more details.

Configuration

# A plugin to collect stats from Opensmtpd - a validating, recursive, and caching DNS resolver
 [[inputs.opensmtpd]]
   ## If running as a restricted user you can prepend sudo for additional access:
   #use_sudo = false

   ## The default location of the smtpctl binary can be overridden with:
   binary = "/usr/sbin/smtpctl"

   # The default timeout of 1s can be overridden with:
   #timeout = "1s"

Permissions

It’s important to note that this plugin references smtpctl, which may require additional permissions to execute successfully. Depending on the user/group permissions of the telegraf user executing this plugin, you may need to alter the group membership, set facls, or use sudo.

$ groups telegraf
telegraf : telegraf

$ usermod -a -G opensmtpd telegraf

$ groups telegraf
telegraf : telegraf opensmtpd

Sudo privileges

If you use this method, you will need the following in your telegraf config:

[[inputs.opensmtpd]]
  use_sudo = true

You will also need to update your sudoers file:

$ visudo
# Add the following line:
Cmnd_Alias SMTPCTL = /usr/sbin/smtpctl
telegraf  ALL=(ALL) NOPASSWD: SMTPCTL
Defaults!SMTPCTL !logfile, !syslog, !pam_session

Please use the solution you see as most appropriate.

Metrics

This is the full list of statistics provided by smtpctl and potentially collected by telegraf depending of your smtpctl configuration.

  • smtpctl bounce_envelope bounce_message bounce_session control_session mda_envelope mda_pending mda_running mda_user mta_connector mta_domain mta_envelope mta_host mta_relay mta_route mta_session mta_source mta_task mta_task_running queue_bounce queue_evpcache_load_hit queue_evpcache_size queue_evpcache_update_hit scheduler_delivery_ok scheduler_delivery_permfail scheduler_delivery_tempfail scheduler_envelope scheduler_envelope_expired scheduler_envelope_incoming scheduler_envelope_inflight scheduler_ramqueue_envelope scheduler_ramqueue_message scheduler_ramqueue_update smtp_session smtp_session_inet4 smtp_session_local uptime

Example Output

opensmtpd,host=localhost scheduler_delivery_tempfail=822,mta_host=10,mta_task_running=4,queue_bounce=13017,scheduler_delivery_permfail=51022,mta_relay=7,queue_evpcache_size=2,scheduler_envelope_expired=26,bounce_message=0,mta_domain=7,queue_evpcache_update_hit=848,smtp_session_local=12294,bounce_envelope=0,queue_evpcache_load_hit=4389703,scheduler_ramqueue_update=0,mta_route=3,scheduler_delivery_ok=2149489,smtp_session_inet4=2131997,control_session=1,scheduler_envelope_incoming=0,uptime=10346728,scheduler_ramqueue_envelope=2,smtp_session=0,bounce_session=0,mta_envelope=2,mta_session=6,mta_task=2,scheduler_ramqueue_message=2,mta_connector=7,mta_source=1,scheduler_envelope=2,scheduler_envelope_inflight=2 1510220300000000000

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