Re: [Bug-tar] Major Bug with tar and incremental backup using the -l and --listed-incremental flags

[Terry Barnaby]

Hi Joerg,

Oh, it seems to make sense to me. My reason for backing up this was was:

1. I have a server with multiple partitions all mounted on the root partition.
2. The system will have additional mounts of /proc /sys /proc/bus/usb etc
        as well as some "mount -o loop d f" mounts.
3. All file systems are mounted on an empty directory.

So to, simply, backup the entire system onto one tape (or compressed file)
        I have used "--one-file-system" to mean don't go down any other file
        systems than the ones listed.

So "tar -c -l -f /dev/st0 --listed-incremental=stamp / /usr /dist /src /home"
would backup the "/ /usr /dist /src /home" file systems but not any others
mounted on the system. The stamp file would be empty for a full backup
and would be used for later incremental backups.

Note that using the same tar command without the "--listed-incremental=stamp"
works fine ....

Is there a better way of doing this backup with tar ?


Terry

Joerg Schilling wrote:
> Terry Barnaby <address@hidden> wrote:
>
>
> > Hi,
> >
> > There has been a major bug (at least to me :) ) in tar since version 1.13.7
> > and it is still there in 1.14.90.
> >
> > I normally perform full backups with a command similar to:
> >
> > tar -c -l -f /dev/st0 --listed-incremental=stamp / /usr /dist /src /home
>
>
> Doing it this way makes no sense with any bckup system.
>
> While star in theory could be enhanced to be able to later find the bounds 
> between the different filesystems (it currently definitlely does not), GNU tar
> does not archive enough information to be able to do so.
>
> The result is a mixture of all 5 filesystems on extraction. It may be that
> the last extract (/home) will remove files from the previous filesystems if 
> deletion on extraction is properly implemented.
>
> Jörg

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