During the peak period of mail sending and receiving, mails are crowded in the queue.

Question

The current email system environment of one of our sites is: Windows server 2016 Standard Edition, exchange 2016 cu23. The version number is: 15.1.2507.32. A certain department has two physical servers using a DAG environment, and they back up each other. 2000 employees evenly distributed across 5 mailbox databases. There are 4 mailboxes in the group, and the number of users in the group is about 1,000. The hardware configuration of each server is 128G memory and 10T SSD.

During the peak email period every day, a large number of emails are sent among employees in this department, and there are also many emails sent in bulk. It will cause a certain amount of mail congestion. If the mail is crowded, an error will be reported.

The error message is as shown below:

Please help with the congestion problem.

Answer 1

Hi @川 苗

Please have a check of the application log in event viewer on your Exchange servers during the peak hours and see if you can find error or warning events like Event 4009, 15004-15007.

And do the affected recipients hosted by a specific mailbox database?

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