I need a solution
Backup-job of a w2012 file-server with DFS fails at weekend only with "E000FF16: the shadow copy resource is not responding, backup set canceled" after about 24h. the daily-job (settings are the same, just no verify) works fine. This weekend tried without verify, but result just the same, only 3h earlier. What also popped up, the performance went down from daily around 2100 MB/sec to 1200 MB/sec. Assuming that during the week more users are online during backup than on weekend, this is not very logic to me.
A second job running parallel, backing up all the servers performs without any problems, with quite similar performance in every job.