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Re: Backup problem using "cp"




On 05/07/2018 08:54 AM, Richard Hector wrote:
On 08/05/18 00:55, David Griffith wrote:
On May 7, 2018 4:31:16 AM PDT, Richard Owlett <rowlett@xxxxxxxxxxx> wrote:
On 05/06/2018 10:11 AM, Thomas Schmitt wrote:
Hi,

Richard Owlett wrote:
Thought I was doing that by specifying -x.

Either cp -x has a bug or the target directory is not in a different
filesystem than "/" and not a mount point of such a filesystem.

Check the device numbers of "/" and "/media/richard/MISC...".
E.g. like this

    $ stat / | fgrep Device
    Device: 803h/2051d      Inode: 2           Links: 25
    $ stat /bkp | fgrep Device
    Device: 814h/2068d      Inode: 2           Links: 7

Here "/bkp" has a different device number (2068) than "/" (2051).
So it (its inode, to be exacting) is in a different filesystem.

As contrast see a directory in the same filesystem as "/":

    $ stat /home | fgrep Device
    Device: 803h/2051d      Inode: 2228225     Links: 60

I get:
richard@debian-jan13:~$ stat / | fgrep Device
Device: 80eh/2062d	Inode: 2           Links: 22
richard@debian-jan13:~$ stat /media | fgrep Device
Device: 80eh/2062d	Inode: 131073      Links: 5
richard@debian-jan13:~$

I gather that "cp" is then an inappropriate tool.

"tar" is inappropriate for my preferences - I was attempting to use
"cp"
as there would be multiple files &/or directories as input *and*
output.

I suspect long term I want "rsync" [ *MUCH* reading to do! ]


You will indeed want rsync.  Essentially, "rsync -av [--delete] <source> <destination> will serve most of your backup needs.


I habitually include -x in there as well, which I suspect will be needed
here.

And for my uses, I always make sure there are trailing slashes on both
source and destination.


My last run was:
 cp -ax / "/media/richard/MISC backups/dev_sda14/"