On Apr 08 06:56:53, sema...@kapouay.eu.org wrote:
> TSS <t...@mg-1.uk> writes:
>
> > Greetings,
> >
> > I've been using this gimmick for backing up some OpenBSD 7.6 systems:
> > https://github.com/thexhr/openbsd-timemachine
> > For the purposes of this discussion, it:
> >
> > 1. uses hotplugd to run a script when you plug in a USB backup drive
> > 2. this script mounts the backup drive
> > 3. it then uses rsnapshot (rsync basically) to back up the data
> > 4. the script unmounts the backup drive
> >
> > Everything is just fine until step 4, when the backup drive refuses to
> > unmount. If you try to do it yourself, you see:
> >
> > umount: /my_backup_mount_point: Device busy
> >
> > This doesn't seem to be a temporary issue: after an hour's wait, the drive
> > still can't be unmounted.
> >
> > I'm not sure how to debug the problem since fstat shows no open file on the
> > drive, nor any process using any directory on the drive as a working
> > directory.
>
> how did you use fstat ? I don't remember well, but using
> 'fstat /my_backup_mount_point' might not be enough.
>
> but you could use:
>
> $ fstat -f /my_backup_mount_point
>
> with -f, fstat will list all opened files in the /my_backup_mount_point
> mount point (at any depth).
For example, as I'm writing this in mutt/vim (paused):
$ fstat /tmp
USER CMD PID FD MOUNT INUM MODE R/W SZ|DV NAME
$ fstat -f/tmp
USER CMD PID FD MOUNT INUM MODE R/W SZ|DV
hans fstat 6559 1 /tmp 25 -rw-r--r-- w 0
hans nvi 16311 4 /tmp 32897* -rw------- r 1474
hans nvi 16311 5 /tmp 32901 -rw------- re 1940
hans nvi 16311 6 /tmp 16449 -rw------- rwe 5120
hans nvi 16311 7 /tmp 4* -rw------- rwe 0
hans nvi 16311 8 /tmp 5 -rw------- re 0
hans nvi 16311 9 /tmp 16450 -rw------- rw 610
hans nvi 16311 10 /tmp 16451 -rwx------ rwe 0
hans nvi 16311 11 /tmp 6* -rw------- rwe 0
hans sh 48868 4 /tmp 32897* -rw------- r 1474
hans mutt 5793 4 /tmp 32897* -rw------- rp 1474
hans ksh 12342 1 /tmp 25 -rw-r--r-- wp 0
> (it should be the same than
> 'fstat | grep /my_backup_mount_point')
Apparently not:
$ fstat /home
USER CMD PID FD MOUNT INUM MODE R/W SZ|DV NAME
$ fstat -f /home
USER CMD PID FD MOUNT INUM MODE R/W SZ|DV
hans fstat 77656 wd /home 466560 drwxr-xr-x r 17408
hans nvi 16311 wd /home 466560 drwxr-xr-x r 17408
hans nvi 16311 3 /home 466929 -rw------- r 34821589
hans sh 48868 wd /home 466560 drwxr-xr-x r 17408
hans sh 48868 3 /home 466929 -rw------- r 34821589
hans mutt 5793 wd /home 466560 drwxr-xr-x r 17408
hans mutt 5793 3 /home 466929 -rw------- rp 34821589
hans ksh 12342 wd /home 466560 drwxr-xr-x r 17408
hans ksh 12342 11 /home 466785 -rw------- rwep 9047
Which is strange, because -f is supposed to
_restrict_ examination to files open in
the same file systems as the named file arguments
Jan
