Forum Discussion

zhaolander's avatar
zhaolander
Level 2
17 years ago

Synthetic backup takes forever to complete

Does anybody have an idea why synthetic backup takes so long to complete? 

The full baseline backup took about 41 hours, 410GB and 1.5million files @ 157MB/min, the daily incremental was 20 hours, 168k files and 144GB @ 112MB/min.  Once the job starts, I don't get any byte count till hours later.  They do complete without any errors, but it just takes forever.  Same data going to tape at around the same rate only takes few hours at most for a full backup and mins for differential.  Is there a solution to solve this problem?

Thanks in advance.
12.x and Earlier
Backup and Recovery
Backup Exec

2 Replies

  • Ken_Putnam's avatar
    Ken_Putnam
    Level 6
    17 years ago
    Does anybody have an idea why synthetic backup takes so long to complete?

    What kind of Disk is this?  RAID?  what level?

    If you just do a standard B2D to a device (B2D Folder) on this same disk, what kind of throughput do you get/
  • zhaolander's avatar
    zhaolander
    Level 2
    17 years ago
    should of clarified but i don't think the disk is the problem.  it is a network appliance and i do regular backups to the same disk and get much faster results.  the differance i see from synthetic and regular backups are,  when i do regular backup, files start being written right away to either disk or tape, but when it's a synthetic job, it seems like backupexec starts to numerating all the files before anything is written to disk.