there are some points worth to think about before you decide how to do backups.

Using ndmp instead of nfs has the follwing impacts: ndmp is blocklevel based, nfs of course is filebased If we backing up a volume that is holding a database, usually the "minimal read ahead" option is set to meet the needs for accessing the database-files. This impacts nfs backup performance dramatically. On the other hand, in order to use ndmp, we need expensive client software for our backup software. But even if we use ndmp to send the data over the network (not a local tapedrive) this backup method is not affecting cached data in the readcache of the filer. This can be a very important reason for ndmp, especially if we are running a database with 7 times 24 hours uptime.

On On-Tap Releases 5.3.5 or newer, the ndmpd version-behaviour can be set using the "ndmpd version [2,3]" command on the filers console.

-----Original Message----- From: Francett, Robert D (SAIC) [mailto:FranceRD@bp.com] Sent: Dienstag, 12. Dezember 2000 01:35 To: 'Shaun T. Erickson'; toasters@mathworks.com Subject: RE: Veritas & Filers, or: to NDMP or not to NDMP ...

Shaun, We use Veritas Netbackup via NDMP and it has worked well. Therefore no worries impacting net with backups. Never used BudTool. Upgrades to DOT have never been a problem. NOW keeps a page which lists NB versions sanctioned with the various DOT releases. I double-check it when considering upgrade. Hope that helps, Bob Francett BP Exploration/Alaska

-----Original Message----- From: Shaun T. Erickson [mailto:ste@research.bell-labs.com] Sent: Monday, December 11, 2000 5:55 AM To: toasters@mathworks.com Subject: Veritas & Filers, or: to NDMP or not to NDMP ...

... that is the question.

I am switching from BudTool to Veritas Netbackup. It seems, if I understand things correctly, that I can either back up my filers over NFS, or I can use NDMP and back them up to a locally attached tape drive, or to another filer with a locally attached tape drive.

NDMP seems the way to go, for performance and speed reasons. However, I stopped using NDMP with BudTool, because everytime I had to upgrade either BudTool or OnTap, I ran into compatability problems between the differing NDMP implimentations.

What has been the experience of those of you who are using Veritas and have tried the above solutions? Which method do you suggest I use, and why?

-ste