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From: Rainer Weikusat <rweikusat@mobileactivedefense.com>
Newsgroups: comp.os.linux.development.system
Subject: Re: shred or scrub
Date: Sun, 27 Apr 2014 20:15:59 +0100
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crankypuss <crankypuss@nomail.invalid> writes:
> On 04/26/2014 08:30 AM, David Brown wrote:

[...]

> You seem to think I'm saying that hardware makers should conform to my
> views of how hardware should work, but what I'm saying is something
> different, I'm saying that the software on the client system needs to
> ascertain the nature of the subsystem that serves it files and behave
> accordingly.

This is not possible. A 'filesystem' is an implementation of an abstract
'user interface' providing certain operation which operates on a block
device, itself an abstract interface to 'all kinds of things providing
it'. This can be something a primitive as a 'floppy disk drive' where
the OS block driver actually has to do stuff like turn the motor on and
off to something as sophisticated as a 'distributed and replicated
[network] block device', ie a cluster of servers implementing a certain
protocol whose 'user interfaces' happens to be 'the block device user
interface',

http://www.drbd.org/home/what-is-drbd/

How filesystems and 'block device thingies' are combined is generally
and administrative descision and even 'ordinary harddisks' are actually
servers connected to local high-speed (or 'not so high-speed') bus which
are operated by exchanging protocol requests and replies with them.