[CentOS] A questiong about replacing my failing drive

Mon Jun 13 02:01:28 UTC 2005
Bryan J. Smith <b.j.smith at ieee.org>

On Sun, 2005-06-12 at 20:52 -0500, Les Mikesell wrote:
> I've never had a problem on systems that have GNU cp (i.e. Linux) using
> 'cp --one-file-system -a ...' to copy complete filesystems as exactly
> as possible.

Some implementations of "cp" still take issue with special files.  E.g.,
the default behavior of cp and most other UNIX utilities is to access
devices nodes, not copy them as the raw device file.

In GNU cp, "-a" = "-dpR" which doesn't handle anything other than links,
files and directories proper, which can be an issue.

> 'rsync --one-file-system -aH ...' will work too.

Again, once you start getting into device nodes and other, special files
than links, file and directories, you can have problems.


> I'm not sure if anyone mentioned that that file-oriented copies: tar,
> cpio, cp, rsync, etc. allow the target to be on a different filesystem
> type than the source, while dump does not,

Correct.  Which is why I like the USTAR archivers (cpio, tar, pax).
You can't trust cp with inodes other than links, files and directories.

> and dd reproduces the original filesystem.

And disk label/slice geometry.  Not always ideal, even if Linux doesn't
trust the device geometry, and overrides with the filesystems' geometry,
by default.


-- 
Bryan J. Smith                                     b.j.smith at ieee.org 
--------------------------------------------------------------------- 
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