On Feb 5, 6:32 pm, Faeandar wrote:
On 5 Feb 2007 13:37:57 -0800, wrote:

Hi,
What formats are the full and incremental dumps from a NetApp OnTAP
system in? As in, is the backup data in some proprietary NetApp
format?

It's just plain 'ol *nix DUMP/RESTORE. Nothing special or
proprietary. It can even be restored from a Solaris machine (restore)
if you fsf past the NBU headers.



Also, what is the difference between NDMP and SnapMirror?

NDMP just uses dump/restore over an NDMP socket. NDMP is a command
protocol, not a data format. It merely handles the commands between
filer and application, the data format is still dump just like any
unix machine.

Snapmirror is not a data format either, it is a transport protocol.
It just happens to be transporting at a block level, the interface of
which is proprietary to WAFL.

The difference between them? NDMP is file level, snapmirror is block.
This can be a tremendous savings in bandwidth depending on your data
set.
Snapmirror is configurable on the filer, NDMP has to be managed
remotely (ie. cron).
Snapmirror has no limits to the number of incrementals it can run.
NDMP (because of dump's limitation) can only run 9 incremental levels.
There are some variations to this but it's generally true.
Snapmirror will delete data on the destination that is removed from
the source. NDMP will only append or add, not delete.

There may be more differences but those are a quick reference.

~F

Thanks

When I have a tier 1 and tier 2 NAS environment (tier 1 is the newer
FAS equip and tier 2 run older hardware with slower drives), should I
run NDMP or SnapMirror to save my dumps on tier 2 for a while before
moving them to tape or is it better to go straight from tier 1 to
tape? That is, I've heard some people use tier 2 as a staging
environment for a while for the backups before they move them to
tape. I am just trying to understand best practices here...

Dvy