MailDrop Queue Test

Messages that have been submitted via the Postfix sendmail command, but not yet brought into the main Postfix queue by the pickup service, await processing in the maildrop queue. Messages can be added to the maildrop queue even when the Postfix system is not running. These messages will be processed only after the Postfix is started. All mails that enter the Postfix queue have to pass through the cleanup service which is responsible for envelope and header rewriting, header and body regular expression checks, automatic bcc recipient processing, milter content processing, and reliable insertion of the message into the incoming queue.

Since the pickup service is single threaded, only one message can be delivered at a time at a rate that does not exceed the disk I/O latency of the cleanup service. If the cleanup service consumes excessive CPU or if the queue is nearly full or if the local message submission rate is high in the maildrop queue, then it indicates congestion of the queue. Also, if the active queue is full, the pikup service may slow down the message injection to the active queue which may also lead to the congestion of the maildrop queue. If the maildrop queue is congested for a longer duration, then new mails may not be accommodated to the queue resulting in slowdown in the reception of mails by the Postfix server. To avoid frequent congestion of the maildrop queue and to figure out the domain to which a large number of messages have arrived in the maildrop queue, administrators can use the Maildrop Queue test.

This test periodically monitors the maildrop queue of the target Postfix mail server and reports the total size of the queue as well as the split up of the message count in terms of time duration i.e., the number of messages that were in the queue for a specified time duration.

Target of the test : A Postfix mail server

Agent deploying the test : A remote agent

Outputs of the test : One set of results for the target Postfix mail server being monitored

Configurable parameters for the test
Parameters Description

Test period

How often should the test be executed.

Host

The host for which the test is to be configured.

Port

The port at which the specified host listens. By default, this is NULL.

UseSUDO

By default, this flag is set to False indicating that the test does not collect the queue related statistics, by default. If this flag is set to True, then the test uses the sudo command to collect the queue related statistics.

Timeout

Specify the duration (in seconds) beyond which this test should time out in the TIMEOUT text box. The default is 30 seconds.

Detailed Diagnosis

To make diagnosis more efficient and accurate, the eG Enterprise embeds an optional detailed diagnostic capability. With this capability, the eG agents can be configured to run detailed, more elaborate tests as and when specific problems are detected. To enable the detailed diagnosis capability of this test for a particular server, choose the On option. To disable the capability, click on the Off option.

The option to selectively enable/disable the detailed diagnosis capability will be available only if the following conditions are fulfilled:

  • The eG manager license should allow the detailed diagnosis capability
  • Both the normal and abnormal frequencies configured for the detailed diagnosis measures should not be 0.

Measures made by the test
Measurement Description Measurement Unit Interpretation

Queue size

Indicates the total size of the queue.

Number

An unusually high number of messages in the queue is indicative of any problem with the corresponding queue or its end points.

The Detailed diagnosis of this measure lists the message count for each domain.

Less than 5 mins

Indicates the number of messages that were in the queue for less than 5 minutes.

Number

 

Between 5-10 mins

Indicates the number of messages that were in the queue for a time duration between 5 to 10 minutes.

Number

 

Between 10-20 mins

Indicates the number of messages that were in the queue for a time duration between 10 to 20 minutes.

Number

 

Between 20-40 mins

Indicates the number of messages that were in the queue for a time duration between 20 to 40 minutes.

Number

 

Between 40-80 mins

Indicates the number of messages that were in the queue for a time duration between 40 to 80 minutes.

Number

 

Between 80-160 mins

Indicates the number of messages that were in the queue for a time duration between 80 to 160 minutes.

Number

 

Between 160-320 mins:

Indicates the number of messages that were in the queue for a time duration between 160 to 320 minutes.

Number

 

Between 320-640 mins

Indicates the number of messages that were in the queue for a time duration between 320 to 640 minutes.

Number

 

Between 640-1280 mins

Indicates the number of messages that were in the queue for a time duration between 640 to 1280 minutes.

Number

 

More than 1280 mins

Indicates the number of messages that were in the queue for more than 1280 minutes.

Number