To upgrade AEE 2.6.4 backup sets, install AEE 3.0.2 first. After upgrading to AEE 3.0.2, then install AEE 3.1.1
Download the file and save it to:
/opt/zmanda/amanda/apache2/htdocs/zmanda-aee/ZMC/BackupSet/Migration.php
Next, type:
chown amandabackup /opt/zmanda/amanda/apache2/htdocs/zmanda-aee/ZMC/BackupSet/Migration.php
chmod u+r /opt/zmanda/amanda/apache2/htdocs/zmanda-aee/ZMC/BackupSet/Migration.php