On top of the Halon MTA web administration's real-time monitoring and queue management, Halon offers email history tracking and reporting based on Elastic. It is integrated into MSUI (and supports other control panels) using session transfer, and works for everything from super administrators to individual users.
The email tracking can, just like the queue manager, find or modify messages based on queries using a wide range of parameters. Those include, but is not limited to; subject, sender, recipient, message ID, IP address, time interval, content filter classification, or any metadata field configured with both exact or partial matching.
Counters and time series data
In addition to the Elastic-based reporting (which is based on transaction logs), Halon MTA also provides statistics in the form of counters. Those counters can be exported to external monitoring systems such as Prometheus and InfluxDB. In addition to the default counters, custom counters can be created for virtually any metric using the memory_inc() function and exported using the API.
Logging can be configured by creating new indices in Elasticsearch once every day, week or month, depending on the traffic load. Since an index can take up to one or more shards in Elastic, there must be an active Elasticsearch Curator cron job that removes old indices. The retention time depends on how many active shards there is in the Elastic cluster.
Below are two screenshots from http://demo-msui.halon.io (username "demo" and password "demo"):