Bug 1958247 - In case of NETFS_KEEP_OLD_BACKUP_COPY=1 and a failure happens during the backup, the old backup is removed also
Summary: In case of NETFS_KEEP_OLD_BACKUP_COPY=1 and a failure happens during the back...
Keywords:
Status: CLOSED ERRATA
Alias: None
Product: Red Hat Enterprise Linux 8
Classification: Red Hat
Component: rear
Version: 8.4
Hardware: Unspecified
OS: Linux
unspecified
high
Target Milestone: beta
: ---
Assignee: Pavel Cahyna
QA Contact: David Jež
Prerana Sharma
URL:
Whiteboard:
Depends On:
Blocks: 1843585 1973448
TreeView+ depends on / blocked
 
Reported: 2021-05-07 13:58 UTC by Pavel Cahyna
Modified: 2021-12-16 13:18 UTC (History)
7 users (show)

Fixed In Version: rear-2.4-19.el8
Doc Type: Bug Fix
Doc Text:
.Loss of backup data on network shares when using ReaR does not occur anymore Previously, when a network file system like NFS was used to store the ReaR backups, in case of an error ReaR removed the directory where the NFS was mounted. Consequently, this caused backup data loss. With this update, ReaR now uses a new method to unmount network shares. This new method does not remove the content of the mounted filesystem when it is removes the mount point. The loss of backup data on network shares when using ReaR is now fixed.
Clone Of: 1843585
Environment:
Last Closed: 2021-11-09 18:53:41 UTC
Type: Bug
Target Upstream Version:
Embargoed:

Attachments (Terms of Use)


Links
System ID Private Priority Status Summary Last Updated
Github rear rear issues 2611 0 None closed ReaR configured with netfs backup can delete other/old folders on NFS at failure 2021-06-18 16:56:48 UTC
Github rear rear issues 465 0 None closed rear configured with netfs backup deletes other folders on NFS at failure 2021-05-07 14:00:18 UTC
Github rear rear pull 2625 0 None closed Fix backup removal in exit task and cleanup handling of URL mountpoints 2021-06-18 16:56:44 UTC
Red Hat Product Errata RHEA-2021:4344 0 None None None 2021-11-09 18:53:57 UTC

Comment 4 Pavel Cahyna 2021-06-07 14:07:46 UTC 
Pull request fixing this problem posted for upstream review, awaiting reply.

As noted in https://github.com/rear/rear/issues/2611#issuecomment-854916232, the issue is actually more serious than the description "If we set NETFS_KEEP_OLD_BACKUP_COPY=1 and an error/interruption after output/default/100_mount_output_path.sh occurs, the exit task will rm -rF all the content of outputfs if the umount does not happen, including the old backup" suggests. It would seem that two conditions must be met for the error to happen: error/interruption during the output stage and umount not happening. Actually, if the umount command fails (for example because the mount point is in use), it satisfies both conditions: umount will not happen and it will be caught as an error leading to program termination and the bug. So the bug is actually more likely than it seems.
Comment 17 errata-xmlrpc 2021-11-09 18:53:41 UTC 
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory (rear bug fix and enhancement update), and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://access.redhat.com/errata/RHEA-2021:4344
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