Agents Administration - Tests
 

Measures reported by Exc2013QueStaTest

A queue is a temporary holding location for messages that are waiting to enter the next stage of processing or delivery to a destination. Each queue represents a logical set of messages that the Exchange server processes in a specific order. In Microsoft Exchange Server 2013, queues hold messages before, during and after delivery. Each queue in the Exchange Server may be in different states as mentioned in the table below:

Outputs of the test : One set of results for each Exchange queue
Queue Status Description
Active The queue is actively transmitting messages.
Connecting The queue is in the process of connecting to the next hop.
Ready The queue recently transmitted messages, but the queue is now empty.
Retry The last automatic or manual connection attempt failed, and the queue is waiting to retry the connection.
Suspended The queue has been manually suspended by an administrator to prevent message delivery. New messages can enter the queue, and messages that are in the act of being transmitted to the next hop will finish delivery and leave the queue. Otherwise, messages won't leave the queue until the queue is manually resumed by an administrator.

Though the queues are accurate indicators of the health of mail flow, it is necessary to identify the state of the queue that is disrupting the flow of mails. Administrators should therefore, continuously track the messages flowing in and out of the queues in each state, so that they can promptly capture bottlenecks in mail flow, before end-users complain. This is exactly what the Exc2013QueStaTest does.

This test automatically discovers the current state of all the queues on the Exchange system, reports the number of messages found in the queues for each state, and also reveals whether/not every queue in that particular state is able to process and send out messages as quickly as it receives them. In the process, the test points to processing bottlenecks, the exact state of the queue in which the bottleneck has occurred, and which stage of mail flow that bottleneck affects.

The state of the queues can be any one of the states described in the table given below:

The measures made by this test are as follows:

Measurement Description Measurement Unit Interpretation
Msg_cnt Indicates the number of messages currently found in the queues of this state. Number A consistent increase in the value of this measure could indicate that the queue is receiving messages, but is sending very few out. This could indicate a processing bottleneck. You may want to compare the value of this measure across queues to accurately identify the queue that consists of the maximum number of messages pending processing. From this, you can determine where exactly processing is bottlenecked.
Inc_msg_rate Indicates the rate at which messages were received by the queues that are in this state. Msgs/Sec  
Out_msg_rate Indicates the rate at which messages were sent from the queues that are in this state. Msgs/Sec  
Status Indicates the number of messages that are entering the queues that are in this state faster than they are leaving the queues that are in this state. Number The drain rate is computed by subtracting the value of the Inc_msg_rate measure from the value of Out_msg_rate measure.

If the resultant value is greater than 0, then this measure reports the value Fast. This means that the messages are leaving the queue faster than they are entering the queue. This could imply a bottleneck at the previous hop.

If the resultant value is equal to 0, then this measure will report the value Balanced. This means that messages are leaving the queue as fast as they are entering the queue. This is also the value you willl see when the queue is inactive.

If the resultant value is lesser than 0, then this measure will report the value Slow. This means that messages are entering the queue faster than they are leaving the queue.

At a basic level, if this measure reports the value Fast or Balanced for a queue, it indicates that the queue is healthy and is efficiently draining. On the other hand, the value Slow for a queue indicates that the queue is not efficiently draining. However, before jumping to conclusions, you also need to consider the values of the Inc_msg_rate, Out_msg_rate, and Msg_cnt measures. For example, a queue for which the Dra_status is Slow, Msg_cnt is high, Inc_msg_rate is high, and Out_msg_rate is low, then it's obvious that the queue is not draining properly. However, a queue with Dra_status as Slow, but also reports very small values for Inc_msg_rate, Out_msg_rate, and Msg_cnt, does not indicate a problem with the queue.
Dra_status Indicates the number of messages that are leaving the queues in this state as fast as they are entering the queues in this state. Number
Fast_dra_status Indicates the number of messages that are leaving the queues in this state faster than they are entering the queues in this state. Number
Ret_msg_cnt Indicates the number of retry messages with this state in the queues. Kbytes In Microsoft Exchange Server 2013, messages that cannot be successfully delivered are subject to a Retry, by means of which a renewed connection attempt is made with the destination. If the length of the retry queue is increasing, it implies that replied messages are unable to reach to next hop. The reason for the bottleneck has to be investigated, isolated, and resolved.
Lock_msg_cnt Indicates the count of locked messages in the queues that are in this state. Number