Managing Organization Limits
The best practice is to terminate a message that is not delivered in a reasonable time from the transport pipeline, and using Organization Limits you can achieve that easily. Let’s say that we configure our organization to 5MB for send and receive, even if we have a Send Connector set to 10MB the mailboxes won’t be able to send any message larger than 5MB internally or externally. As a thumb rule the Organization Limits should be the largest value in your environment, although you can work with exceptions at user level but it’s not recommended. Eventually, it will become a pain to manage those special users.In order to configure the organization limits we can open Exchange Management Console, expand Organization Configuration, Hub Transport, click on Global Settings tab and then double click on Transport Settings, as shown in figure 01.
Figure 01
Let’s start our exercises changing the value of Maximum receive size (KB) to 5MB (5120KB) to understand the implication of this change.
Now, our organization is restricting users to receive a maximum of 5MB messages, however the send limit is still 10MB and we may face the first issue, where a user can send a 10MB message but all other internal recipients won’t receive it. Even if the user tries to send himself a message larger than 5MB he would be able to send but he would also receive an error message explaining that it couldn’t be delivered due the limit restrictions.
Let’s try to send a message with one or more attachments where the total size of the message is larger than 5MB. The result will be a system message to the sender as shown in Figure 02. The diagnostic logging informs the administrator that the problem is on the receiving portion and we know that by the Resolver.RST.RecipSizeLimit string at the end of the NDR code.
