[Novalug] is this obvious (to everyone but me?)

James Ewing Cottrell III JECottrell3@Comcast.NET
Sun Apr 12 23:00:12 EDT 2015


On 4/12/2015 5:34 AM, Rich Kulawiec via Novalug wrote:
> On Sat, Apr 11, 2015 at 07:25:59PM -0400, James Ewing Cottrell III via Novalug wrote:
>> I would avoid dump. It's pretty obsolete, and there is even concern
>> that it work on ext based filesystems. There is a better way.
>
> Nonsense.  It works *beautifully* on ext-based filesystems. (And on
> UFS-based ones.)

At some point, dump was argued against by no less a person than Linus 
himself. That said, I wasn't entirely convinced. Other indications 
pointed to a faulty driver. This was Circa Red Hat 9, so no doubt the 
issue has long been fixed.

But the problem here is that since dump looks under the covers, it must 
be rewritten for every type of filesystem. Is there a reiserdump? A 
btrfsdump? Lustredump? Glusterdump? Gfsdump?

> I know, I've used it extensively for decades in all
> kinds of operations and it has never failed to yield a usable backup.
> (I test them all with restore post-dump to make sure that they're
> readable/intact/etc.)  And while the run-time performance on Linux isn't
> as good as the performance on BSD or Solaris (due to implementation
> differences) the ability to perform incremental dumps almost always
> means, in practice in production environments, that it doesn't matter.

There are other ways of doing incrememntals.

> Besides, as I pointed out, a copy made with rsync is just that: a copy.
> It's not a backup.

I don't see any difference. A Backup is just a Copy too.

You didn't even address the Tape vs Disk issue. Dump seems to be 
hardwired for Tape. Some of us would rather Dump to Disk. In a format 
that can actually be Used Actively.

> ---rsk

JIM




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