You can use 'mt' to mount a tape, enable diagnostics, and some rudimentary testing of the device.
If you are using ndmp to perform the restore, you can enable debugging ('ndmpd debug 70' for max info) to see if there are any issues there.
sysstat could be helpful during the restore to try to determine any bottlenecks on the filer end. Also, the syslog for any SCSI
Restores will be slower than backups. I don't know the max's for the FAS6070, but when we had an R200 we saw that we could run about 200MB/sec backups with the CPUs at 100%. According to a NetApp engineer the max that an R200 could write to disk was about 50MB/sec. 15GB/24hr restore is incredibly slow. We've replaced our R200 with a FAS6070 with 6ea LTO-4 drives and backup 8TB daily over an 18hr period. I haven't actually timed my test restores as they have always seemed to be within acceptable time periods.
I don't know if it makes a difference, but we don't use the onboard FC ports for our tape drives. We use quad port FC tape adapters.
On Thu, Sep 18, 2008 at 7:23 PM, A Darren Dunham
<ddunham@taos.com> wrote:
I'm trying to restore a file on a filer (via NetBackup) and the restore
is *crawling* (a few KB/s on avg).
One test I'd normally do would be to simply mount this tape up on the
system and test that I could read it quickly. Is there any way to do
this directly on the filer? I see 'dd', but I don't see how to read
from the tape device.
I don't think I can run a 'restore' because the data on the tape will be
wrapped with NetBackup header information. I just want to test that the
data can be read quickly. So actually interpreting the data isn't
important at this point.
Thanks.
Background: Directly attached LTO3 drive. Backups are normally nice
and speedy (50+ MB/s). ndmpd probe suggests that it's read 15GB of data
in over 24 hours. *way* too slow.
--
Darren