already twice I faced the issue that Clonezilla live was not able to restore a backup due to an CRC error in the image files. Partimage did report the CRC error and I was able to confirm it by runniing gzip in test mode on the backup.
I have two questions/comments regarding this:
1.)
Now, after creating a new backup, I will always manually check the image with gzip for CRC errors (e.g. cat `ls sda2*`|gzip -tv - ). Is such a functionality for checking backup integrity automatically AFTER BACKUP CREATION already availabe somewhere in Clonezilla? If not, it would be nice if this could be imnplemented.
I think the feature to create a MD5 checksum for the backup doesn't really help here. As far as I understand the MD5 checksum is calculated for the compressed image. This won't help if something goes wrong during the compression process.
2.)
For the backup where this did happen recently, the CRC error occours at around 80% of the gziped backup. I have another, valid backup which is only around a week older. So I can restore most things by first deploying the older backup and then the more recent, broken backup on top. Which just leaves some file system inconsistencies and maybe some lost changes in the last 20% of the backup which is corrupted.
At the end of the restore process Clonezilla is apparently fixing these file system inconsistencies. At least I can see lots of messages which seem to come from fsck or the like. Cleaning up orphaned files etc. Though the messages are disappearing too fast in order to remember any details. Is this information stored in some logfile? I can't find it anywehre in /var/log. This information could be helpful in order to determine which files might be missing or corrupted between the last, valid backup and the most recent broken backup.
If it's not logged, I could probablyl also run the restore manually from command prompt and redirect sdout intot some file. Nevertheless it would be nice, if Cloezilla would log this somewhere.
Thanks.
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"it would be nice if this could be imnplemented" -> There is no wrapper program to check that. However, yes, you are right, you can use gzip and partclone.chkimg to check the saved image. We will try to implement that. Please keep pushing us.
"Is this information stored in some logfile? I can't find it anywehre in /var/log." -> No. We will try to log that in the future release.
Thanks.
Steven.
If you would like to refer to this comment somewhere else in this project, copy and paste the following link:
Hi,
already twice I faced the issue that Clonezilla live was not able to restore a backup due to an CRC error in the image files. Partimage did report the CRC error and I was able to confirm it by runniing gzip in test mode on the backup.
I have two questions/comments regarding this:
1.)
Now, after creating a new backup, I will always manually check the image with gzip for CRC errors (e.g. cat `ls sda2*`|gzip -tv - ). Is such a functionality for checking backup integrity automatically AFTER BACKUP CREATION already availabe somewhere in Clonezilla? If not, it would be nice if this could be imnplemented.
I think the feature to create a MD5 checksum for the backup doesn't really help here. As far as I understand the MD5 checksum is calculated for the compressed image. This won't help if something goes wrong during the compression process.
2.)
For the backup where this did happen recently, the CRC error occours at around 80% of the gziped backup. I have another, valid backup which is only around a week older. So I can restore most things by first deploying the older backup and then the more recent, broken backup on top. Which just leaves some file system inconsistencies and maybe some lost changes in the last 20% of the backup which is corrupted.
At the end of the restore process Clonezilla is apparently fixing these file system inconsistencies. At least I can see lots of messages which seem to come from fsck or the like. Cleaning up orphaned files etc. Though the messages are disappearing too fast in order to remember any details. Is this information stored in some logfile? I can't find it anywehre in /var/log. This information could be helpful in order to determine which files might be missing or corrupted between the last, valid backup and the most recent broken backup.
If it's not logged, I could probablyl also run the restore manually from command prompt and redirect sdout intot some file. Nevertheless it would be nice, if Cloezilla would log this somewhere.
Thanks.
"it would be nice if this could be imnplemented" -> There is no wrapper program to check that. However, yes, you are right, you can use gzip and partclone.chkimg to check the saved image. We will try to implement that. Please keep pushing us.
"Is this information stored in some logfile? I can't find it anywehre in /var/log." -> No. We will try to log that in the future release.
Thanks.
Steven.