Some days ago i run into a problem with Veeam: My repository server crashed while backing up my customers virtual machines. in fact, the vSphere server on which the repository server is running had a purple screen. This was not the first time this happens but it was the first time my existing backups where no longer usable and further jobs stopped with an error: [StorageSortedList] Internal error: circular references near storage Veeam.Backup.Core.CStorage is found.
This error appears if you start again the backup job or if you open “properties” of you backup set. because google did not even find one entry about this error i posted it on the forums of veeam and tried to find a solution myself. unfortunately i was not successful so far. my workaround was to backup all veeam repository (backup) files and start over with a new set. To do so you have to also delete the database records for those backups. after that you can start over with a new set.
As far as i know this happens only if you have configured forward-incremental with synthetic full and your backup server crashes while transforming the synthetic full. i still wait for an answer from veeam and will update the post as soon as possible.