I must apologise for being half-asleep and therefor overlooked the
significance of the request ;-).
Pse note, the following are real results obtained while testing with a
representative mix of user data.
There were a few restrictions at the time: I was only able to use a
single FC port on an F880 and the 4 LTO 1 tape drives were attached to
two FC-SCSI routers.
Networker 6.1.3, Ontap 6.3. Administration = History
Backup	Data		Including			Excluding 
Operations	Volume	Administration		Administration
				MB/sec	GB/Hr		MB/sec	GB/hr
1		122		22,3		80		25,1
90
2		244		38,4		138		47,3
170
3		366		51,7		186		63,5
229
4		488		59,8		215		77,5
279
The following assumption was made based on backup and recover tests:
backup +- 50 GB/Hr, recovery +- 25GB/Hr
Operations	Backup			Recovery
		Estimated	Measured	Estimated	Measured
		GByte/Hr	GByte/Hr	GByte/Hr	GByte/Hr
1		50		80		25		62
2		100		138		50		120
3		150		186		75		144
4		200		215		100		160
Btw. I just remembered, the Networker server was a PC with a 200 Mhz
Pentium, 128 Mbyte RAM.
Bye
Ernie
-----Original Message-----
From: owner-toasters(a)mathworks.com [mailto:owner-toasters@mathworks.com]
On Behalf Of Geoff Hardin
Sent: Tuesday, May 18, 2004 11:53 PM
To: toasters
Subject: NDMP backup speeds
Toasters,
    What is the general consensus for NDMP backup speeds?  I have four
older 
F760Cs that are getting about 5-6 MB/s to local tape drives.  The
problem is 
that I also have another nine filers (1 F630, 1 F720, 1 F740, 6 F760C)
that are 
backing up via 3-way NDMP and we are lucky to see 4-5 MB/s; most are in
the 1-2 
MB/s range.  And don't even get me started on the
Solaris/SunOS/Linux/HP-UX/DEC 
clients that backup through the drives attached to the filers (0.1 - 2
MB/s).
    We were looking at upgrading the tape drives and such, but we have
done a 
few test dumps from filer to filer, filer to LTO-2, and filer to LTO-2
attached 
to a Sun, and the numbers didn't improve much (definitely not enough to
justify 
buying a new tape library / tape technology).
Just a little background:
    We are using DLT7000 tape drives, which should have a maximum
through put of 
about 10 MB/s (2:1 compression), contained in a Quantum P3000 library.
We have 
all our filers on two separate networks; one for general data sharing
and a 
private one for our backups.  The private network is all GbE (fibre)
using the 
Alteon GbE cards (Gigabit Ethernet Controller II).
    We are doing qtree dumps, and while some of the filers have only
four qtrees 
per volume, others have over 40.  Each qtree is generally capped at 200
GB max, 
and for those filers that have lots of qtrees, we still try to limit
each 
saveset to around 200 GB.
    So, I guess what I'm really asking is 1) "What kind of speeds are
you 
seeing?" and 2) "Am I doing something wrong?"
Many thanks,
Geoff Hardin
geoff.hardin(a)dalsemi.com
Difficulty is the excuse history never accepts.