wimlib

Hello,
I've read viewtopic.php?f=1&t=327 but it seems different in my case ( no --update) :

version : 1.12.0
windows 10

wimcapture.cmd --wimboot --snapshot --pipable c:\ - 'Windows_10' | plink -v -ssh -pw <mypass> root@10.10.3.100 "cat > /data2/win3.wim"

[ERROR] A file was concurrently modified!%) done
Path: "\??\GLOBALROOT\Device\HarddiskVolumeShadowCopy3\Users\ceboxadmin\VirtualBox VMs\win10\win10.vdi"
Expected SHA-1: 5681f8309dc73c7dc62723cda4c1aae0446813ba
Actual SHA-1: 6ab5f760be73d39dc8443eea35d1c2c2fa6ec105

ERROR: Exiting with error code 88:
A file being added to a WIM image was concurrently modified.
Sent EOF message
Server sent command exit status 0
Disconnected: All channels closed

it's always the same file that seems concurrently modified, but this file is not modified ( creation, modification time attributes)
Regards,
Nicolas



PS C:\WINDOWS\system32> .\vssadmin.exe list shadows
vssadmin 1.1 - Outil ligne de commande d�administration du service de clich� instantan� de volume
(C) Copyright 2001-2013 Microsoft Corp.

Contenu du jeu de clich�s instantan�s n� : {7c5b18da-9fb2-4d24-98d9-729f0a86ee87}
Contenait 1 clich�s instantan�s � la date de cr�ation : 16/01/2018 10:25:52
ID du clich� instantan� : {c6335871-0149-4e67-9ea8-627062dba4ab}
Volume original : (C:)\\?\Volume{a75c81c7-c287-47e1-90b2-f3f49d629380}\
Volume de clich� instantan� : \\?\GLOBALROOT\Device\HarddiskVolumeShadowCopy3
Ordinateur d�origine : DESKTOP-MD44MQ9
Ordinateur de service : DESKTOP-MD44MQ9
Fournisseur : 'Microsoft Software Shadow Copy provider 1.0'
Type : Backup
Attributs : Diff�rentielle

It looks like you have a VirtualBox VM running. Is that the case? If so, shut it down, or suspend it at least, before running the capture.
A virtual machine is always changing state and could be writing to the preallocated image file for any number of reasons w/o changing the file size.

No, this is strange but virtualbox does not runs. ( and the size does not change )
And before this test, an other file has the same issue, and not cover by any virtualBox or program.
I had this issues since I ve done some clean via windows clean drive tool .

in a general way, there's always file modified during backup (antivirus, or auto save document) , how can backup them with --snapshot ?


Regards,
Nicolas

Hello again,
I suppress *.vdi file and now :
[WARNING] Creating a pipable WIM, which will be incompatible
with Microsoft's software (WIMGAPI/ImageX/DISM).
Using XPRESS compression with 4 threads
[ERROR] A file was concurrently modified! done
Path: "\??\GLOBALROOT\Device\HarddiskVolumeShadowCopy6\Users\ceboxadmin\AppData\LocalLow\Oracle\Java\jdk1.8.0_121_x64\sj180121.cab"
Expected SHA-1: 03f93ea29478d6fe533612b879da5b20fae16884
Actual SHA-1: 39c00bdfc6f49f8ea0eb9a5a06e8e654a2020e9a

ERROR: Exiting with error code 88:
A file being added to a WIM image was concurrently modified.
Sent EOF message
Server sent command exit status 0
Disconnected: All channels closed

an other one ...

I usually do offline backups from Linux w/ wimlib so I may not have the solution for you.

The one piece of advice I'd give you is to temporarily disable any antivirus and and shutdown any VM's that you have running before attempting the backup, as these are both accessing the system at low levels and may not cooperate with requests to 'be still' prior to a snapshot.

...and unless there's a reason for it, close EVERYTHING else as well.

so -snapshot is a fake option ?

Please don't misconstrue what I said. Snapshot is working for many people. Those are just practices I would do if I were creating a live image. Again, I'm sure someone else may have better advice for you on this issue.

Good luck.

Hello again,
After playing with option, it seems that's pipaple option that is the issue.
-snapshot only is ok to backup live system
-snapshot -pipable shows my issues ( checkum error)

I think it is a bug
regards,
Nicolas Prochazka

I'm not able to reproduce this.

--pipable should not really make a difference, but it does cause all files to be checksummed earlier, rather than as they are written. So, if the contents of the so-called "snapshot" are changing, with --pipable there is a much larger window for those changes to be detected.

On Windows, --snapshot support uses Volume Shadow Copy Service, so it is only as reliable as that. If VSS is broken on your system then programs that use that API probably can't do anything about it, other than perhaps silently corrupting your data rather than giving an error like wimlib does.

hello,
this is 100% reproductible, on my windows10 and other one, when create wim from entirely c:\
vssadmin command seems to work correctly.
Is it possible to not stop the process is checksuming false ?
regards
Nicolas