We have several filers and few tape drives so we are looking at doing 3-way NDMP backups. Right now, we are doing those backups to other filers, but this is consuming a lot of resources, especially on the tape host filer. So, we are looking at a new tape library from SpectraLogic, Overland, Quantum, StorageTek, etc. that has the NDMP "built-in" to the tape drive.
Our question is, what kind of speeds are others seeing in their real environments? Speaking to one vendor, they claimed their library would work at the rated tape speeds (35 MB/s), while another claimed even better performance (40 MB/s); to his credit, the second vendor said that he wasn't the technical guy, but he thought that's what he remembered. Call me overly cynical, but I find it hard to believe that we will see speeds comparable to direct attached tape over the network. Our experience in the past has been somewhere closer to 50% of the rated tape speed, and even that may be a bit overreaching for some of our older filers (F760C).
Thanks,
Geoff Hardin geoff.hardin@dalsemi.com UNIX System Administrator Maxim / Dallas Semiconductor