Netbackup 7.6.0.3 (2.6.0.3) backup miss to backup files when using change jurnal.

[Bengt_H]

Environment is Netbackup Appliance 2.6.0.3 as media server, Windows 2008R2 7.6.0.3 as master server, client is Windows 2008R2 7.6.0.3 and policy type MS-Windows.

When doing incremental backup using accelerator and change journal is enabled on the client, the incremental backup miss to back up some files that has changed sense last incremental backup! The file in question is an .mdb file and has a new timestamp and archive flag set in the file system.
I have tried to back it several times with change journal enabled and it misses the file!

When disabling change journal and doing backups using timestamps the backup works and the file in question gets back upped.
Also the incremental backup with change journal enabled is 12818 kB in size but when doing the exact same backup just minutes later without the change journal the backup gets up to 26321191 kB! In the details of the backup, in both cases the backup is reports as successful, with no files missed!

I will do some more testing of this issue in a lab environment and see if I can repeat the issue. Anybody else that expense this problems?

[Mark_Solutions]

Are you sure it is not excluded for that client .. no one would normally backup an mdb file in a file system policy as it is usually an open database file which should be excluded for file system backups and backed up using an agent where possible.

As no files are skipped i would check the exclude list

For the difference in size i am unsure how you acheive that .. perhaps one uses time stamps, track log and one archive bits which would give quite a different result

[Bengt_H]

I completely agree that .mdb file should not be backed up, but this is a common file share at a large customer and the users don’t know that .mdb file is a big issue when it comes to backup so they put them there anyway because the need backup of the database…

And no the file is not excluded, if it is was it should not be backed up when I just deselect Use Change Journal it would still be excluded.

The difference in size of the backup makes me the scariest, it implies that a large amount of files are skipped when change journal is used!

The only thing I have done between the two backups that differs in size is unselected use change journal. I run one with change jurnal enabled = small backup, when it was finished I run the same backup again without change journal = big backup.!

[Bengt_H]

I have not been able to replicate the exact same, as described in the first post, behavior in my lab environment. But I have encounter another strange behavior when using change journal.

Accelerator enabled MS-Windows backups by default tries to use change journal, it creates VxCJDelete.dat, VxCJInfo.dat and VxCJMon.dat in the root of the drive, even if use change journal is not enabled at the client!

When running incremental backups it seems to back up the same data over and over again even if it has not changed! Or at least it catalogs it, I can see it in BAR… (98058 kB, 117 files in my test)
When I enable use Change Journal the amount of data and files in the incremental backup reduces (now 111 Kb, 44 files)

But when I disable Change Journal again its back as before with exactly the same amount of data and files as before (98058 kB, 117 files).

In my humble mind running incrementals one after another without changing the data should generate a minimal of data in each incremental backup (0 kB, 0 files) not the same amount over and over again…

Maybe i should test this in 7.5 also...

[RonCaplinger]

Are you running a full backup between these incrementals?  When you enable the Change Journal option, you need to run a full backup once so that the change journal is "zeroed out" and only new changes are tracked after that. 

Disabling the Change Journal and running an incremental would likely back up fewer files if you use the archive bit instead of the date field.

[Bengt_H]

I found the problem with my testing of incremental backups!
The setting Time Overlap on Client settings is default 60 minutes.
With this setting the file timestamp has to be at least 60 minutes older then the previous incremental or full backup to NOT get selected. I have run the second incremental backup before 60 minutes has passed and therefore all files are backuped again. This fact makes incremental behave like cumulative backup.

But I still don’t understand how this affects the problem in my first posting, why is the file not backed up.
Have to check the timestamps on it more carefully,

Can it be because it is a .mdb file, and the timestamp on the file is not updated when data is written to the database?