4.x can't read 5.x dump?

Adrian Wontroba aw1 at stade.co.uk
Fri Dec 3 18:03:51 PST 2004

On Fri, Dec 03, 2004 at 02:36:09PM +0000, Ceri Davies wrote:
> > > Should I expect a dump taken from 4.X to be restorable on 5.X though?
> > Yes.
> Phew.

I didn't even think about the possibility of dump not being forwards
compatible (8-(

In passing, you may find the buffer port useful.  I spent a while a
couple of years ago experimenting with settings, and find this sort of
thing sufficiently fast:

/sbin/dump -L -0 -u -C 32 -b 32 -f - /home |
	/usr/local/bin/buffer -s 32k -m 16m -t |
	gzip  | 
	/usr/local/bin/buffer -s 32k -m 16m -t > new/home.dump.gz

That is, big buffers and block sizes for dump, with a 16 MB buffer of
either side of gzip to absorb some of the delays in compression or
writing the dump file.  Sorry, no timings available at the moment.

* Remove the -L under Release 4
* When the above line is executed, the script has changed its CWD to the
  dump directory, usually on an NFS mount.
* When dumping to the same machine, I include -h 0 and make the dump
  directory (and a slew of other recoverable by other ways ones) nodump
  with chflags nodump.

Adrian Wontroba

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