By default, Service Desk and CMDB allow Attachments to be of unlimited size.
It is recommended practice to limit the maximum size of Attachments both to conserve disk space and limit unreasonable use of network bandwidth.
This setting can be changed through the Service Desk/CMDB Administrator interface.
CA Service Desk Manager - All Versions.
Log into the web interface as an Administrator Access Type user.
From the "Administration" tab, "Attachment Library" folder choose the "Repositories" node.
In the right panel repository list, right click on the desired repository and choose "Edit". In the Repository Detail Page which pops up and enter the desired maximum file size under "File Limit Size(KB)" and "Save." Note that the default value for "File Limit Size(KB)" is 0 and indicates that there is no restriction on the file upload size.
The maximum file size depends on the business requirements. For example, what size of file is required for Analysts to effectively perform their work? Is there adequate disk space? Adequate network bandwidth? How many Attachments are expected per day? And so on.