Please help us to have the steps to upgrade from 10.3 to 10.8.
Release : 10.3
Please review the knowledge and case docs
https://knowledge.broadcom.com/external/article?articleId=243098
https://techdocs.broadcom.com/us/en/ca-enterprise-software/it-operations-management/application-performance-management/10-8/ca-apm-release-notes.html Review Release Notes and Check Compatibility Guide
https://techdocs.broadcom.com/us/en/ca-enterprise-software/it-operations-management/application-performance-management/10-8/upgrading.html Choose Upgrade Process to Use
At the bottom of the page you will find checklists and other useful steps
-Checklist: Manually Upgrade CA APM
-Prepare for Manual Upgrade
-Upgrade Components
-Complete the CA APM Upgrade
-Backup and Rollback During CA APM Upgrade
-View and Apply Property Configuration Changes
-Upgrade Introscope Manually
Upgrade the APM Database Manually