Last Login (last-login) Plugin

This plugin can be used to update user's last-login timestamp in a configured dictionary.

Last login information is useful for troubleshooting scenarios, which usually starts with end user contacting customer care agent that the mailbox is unreachable or empty. Amongst the first things is to check when the customer last successfully did login to the mailbox and using which protocol, as this might indicate that there might be some device with POP3 configured thus emptying the mailbox. Last login feature is designed for this use case, to allow easy way to search per any account the timestamp of last login or last mail delivery to the mailbox.

Last login information is also useful in determining system usage statistics.

Settings

last_login_dict

Default	[None]
Value	string

The dictionary where last login information is updated.

Example:

plugin {
  last_login_dict = redis:host=127.0.0.1:port=6379
}

last_login_key

Default	last-login/%u
Value	string

The key that is updated in the dictionary (defined by last_login_dict) with the last login information.

last_login_precision

Default	s
Value	string
Allowed Values	smsusns

Precision for last login timestamp.

Example Configuration

protocol imap {
  mail_plugins = $mail_plugins last_login
}
protocol pop3 {
  mail_plugins = $mail_plugins last_login
}

plugin {
  last_login_dict = redis:host=127.0.0.1:port=6379
  #last_login_key = last-login/%u # default
}

In this example, last_login plugin is explicitly enabled only for imap & pop3 protocols.

If enabled globally, it'll also update the timestamp whenever new mails are delivered via lda/lmtp or when doveadm is run for the user. This can also be thought of as a feature, so if you want to update a different timestamp for user when new mails are delivered, you can do that by enabling the last_login plugin also for lda/lmtp and changing the last_login_key setting to include %{service}.

MySQL Example

This includes the service and remote IP address as well.

dovecot.conf

plugin {
  last_login_dict = proxy::sql
  last_login_key = last-login/%{service}/%{user}/%{remote_ip}
  last_login_precision = ms
}

dict {
  sql = mysql:/etc/dovecot/dovecot-dict-sql.conf.ext
}

SQL Schema

CREATE TABLE last_login (
  userid VARCHAR(255) NOT NULL,
  service VARCHAR(10) NOT NULL,
  last_access BIGINT NOT NULL,
  last_ip VARCHAR(40) NOT NULL,
  PRIMARY KEY (userid, service)
);

dovecot-dict-sql.conf.ext

connect = host=sql.example.com dbname=mails user=dovecot password=pass

map {
  pattern = shared/last-login/$service/$user/$remote_ip
  table = last_login
  value_field = last_access
  value_type = uint

  fields {
    userid = $user
    service = $service
    last_ip = $remote_ip
  }
}

Cassandra Example

This includes the service and remote IP address as well.

dovecot.conf

plugin {
  last_login_dict = proxy:dict-async:cassandra
  last_login_key = last-login/%{service}/%{user}/%{remote_ip}
  last_login_precision = ms
}

dict {
  cassandra = cassandra:/etc/dovecot/dovecot-dict-cql.conf.ext
}

Cassandra Schema

CREATE TABLE last_login (
  userid TEXT,
  service TEXT,
  last_access TIMESTAMP,
  last_ip TEXT,
  PRIMARY KEY ((userid), service)
);

dovecot-dict-cql.conf.ext

connect = host=sql.example.com dbname=mails user=dovecot password=pass

map {
  pattern = shared/last-login/$service/$user/$remote_ip
  table = last_login
  value_field = last_access
  value_type = uint

  fields {
    userid = $user
    service = $service
    last_ip = $remote_ip
  }
}

Alternative Schema Cassandra Example

Instead of using a separate last_login table, add different services as separate fields to the main users table.

dovecot.conf

plugin {
  last_login_dict = proxy:dict-async:cassandra
  last_login_key = last-login/%{service}/%{user}/%{remote_ip}
  last_login_precision = ms
}

dict {
  cassandra = cassandra:/etc/dovecot/dovecot-dict-cql.conf.ext
}

Cassandra Schema

CREATE TABLE users (
  userid TEXT,
  last_imap_access TIMESTAMP,
  last_pop3_access TIMESTAMP,
  last_lmtp_access TIMESTAMP,
  last_imap_ip TEXT,
  last_pop3_ip TEXT,
  last_lmtp_ip TEXT,
  PRIMARY KEY ((userid))
);

dovecot-dict-cql.conf.ext

connect = host=sql.example.com dbname=mails user=dovecot password=pass

map {
  pattern = shared/last-login/imap/$user/$remote_ip
  table = users
  value_field = last_imap_access
  value_type = uint

  fields {
    userid = $user
    last_imap_ip = $remote_ip
  }
}

map {
  pattern = shared/last-login/pop3/$user/$remote_ip
  table = users
  value_field = last_pop3_access
  value_type = uint

  fields {
    userid = $user
    last_pop3_ip = $remote_ip
  }
}

map {
  pattern = shared/last-login/lmtp/$user/$remote_ip
  table = users
  value_field = last_lmtp_access
  value_type = uint

  fields {
    userid = $user
    last_lmtp_ip = $remote_ip
  }
}