#01715660 for us. 10G network infrastructure for the most part, Dell TL2000 6G SAS connected to Dell PE430 physical server, pulling from EMC Data Domain and Dell DR dedupe devices - DR's are 10G and DD's are 1G.
We were seeing around 20-30 or so MB/s files to tape - don't even try GFS w/ a dedupe source because of the transformations it does, those were 2-3 MB/s, stick to file to tape and live w/ it - I think our DR file to tape jobs (10G) were maybe around 50-60 MB/s.
Before anyone scoffs it off to pulling files from a dedupe device please, we can robocopy files from dedupe to the local tape server HDD at around 100 MB/s from the old 1G connected DD's and ~200-375 MB/s from our 10G connected DR's. Network speed appears to be there. We can backup files to tape from tape server HDD to tape at around 160 MB/s, so tape speed appears to be there (hardware encryption and compression enabled since, they're tapes, and coming from dedupe they're not compressed). Pulling across the network to tape, dismal speeds.
I've been working w/ patient and helpful first tier support for a week or two to experiment w/ different block sizes at the tape drive w/ mixed and inconclusive results. Overall it seemed like V9's default of 1MB blocks might be too large since it seemed to perform better in our setup at somewhere around middle of the road block size. We're currently set at 131072 in Veeam drive properties but per below, I think one of the registry hacks a higher engineer did was to set a different block size. Our fresh V9 install had set them to 1048576. Using Veeams tape performance testing utility did seem to confirm that on average somewhere around middle or lower block size gave best overall performance.
Last week support graciously got us escalated to an engineer, whom after a webex, very respectfully, threw a slew of registry hacks, and jacked w/ the tape server's network card, and got us down to around 12 MB/s copying files from the network to the tape server HDD, and around 823 KB/s tape speed, at which point he declared we clearly have network issues that we need to straighten out and call them back.
After putting back the tape server's NIC to where it was before the webex, we have our network speed back and surprisingly this morning our tape jobs are running pretty decent speed! Around 109-133 MB/s off our 10G DR's, we were getting much lower before. I don't know if it was experimenting w/ block size in Veeam or all the registry hacks that did it, but we're doing reasonably well this morning. I would argue it was not our network since there was no real change there (I had to put it back the way it was before the engineer). I'm going to let the monthly tape jobs run and see how overall performance comes out, and may even try the next smaller block size to see what difference that makes. We're much better, though I can't say what exactly may have fixed it other than try experimenting w/ block size, run a few jobs, and see what works best for you.
Veeam B&R v9
Dell TL2000 via PE430 (SAS)