Error truncating file while incremental backup with btrfs and CBT client


#1

Hello,

I have UrBackup running in a NetGear NAS, which is armel architecture based (armv7l). It is running with BTRFS storage and it is working very fine from a few weeks ago. I installed UrBackup from sources into this NAS. The OS is a Debian 8 fork from NetGear.

I receive this error in two of my clients when do incremental backup:

I have seen this error a few days ago in other of my clients and it was exactly the same, also with a PST file. Then I have do some tests and finally I found that when I do a complete bakcup of this client the problem dissapears and subsecuent incremental backups works again.

But now it is happening again in other two different computers, so I think I must ask for support.
The clients are running Windows 7 Pro x64 and x86 with CBT client. Anyway I think this is a server issue.

I think the problem is in some place whit the snapshoting system. I have seen that snapshots for those failed backups are not deleted:

error3

I think if I do a complete backup of this client It probably fix the error, but I think probably it will happen again.
¿Any idea?

Thank you so much.


#2

It cannot resize the file during backup (system call fails). Probably a btrfs issue.

Is your pst file really that large (~23 GB)?


#3

Hello,
Yes, these files are larger than 23 GB. Is there any workaround?
Why works for some time and then it fails?
Do you think this is a problem of the btrfs implementation of this NAS?


#5

Hello,

I have seen that in the other client that is failing, the data amount is much fewer than 23 GB… I attach the error log


#6

Hello,

@uroni any help on this?
Do you think it is a BTRFS issue in this NAS? or a UrBackup issue?

FYI, I have seen also that in these clients, the post incremental batch file is running like the backup has finished correctly.

Many thanks.


#7

Hello,

Can you give any hints about any prossible solution to this problem?
As I tell in previous messages, the problem dissapears when I do a full file backup of these clients, after that, incremental backups are working again.

Thank you.


#8

Update the linux kernel on the device to e.g. 4.14 (I know this probably won’t be possible, so you’ll have to use another fs or run UrBackup in a VM).


#9

Ok, I will evaluate these options.

Thank you.