Bare-metal Restore
Wesley Smith's Mac TiBook laptop disk died recently. Fortunately I was able to do a bare-metal restore using NetWorker. OSX doesn't us ordinary Unix flat files for some/most/all? system settings, so I also had to do some NextStep magic (!) to recover the NetInfo database. Crazy man.
SDLT Backups
I installed a Quantum SuperLoader with sdlt600 tape drive on our lowly Sun Ultra5 NetWorker backup server recently. After increasing the parallelism to eight, we're realizing 9.5 MBps (76 Mbps) write performance. The network traffic graph shows the server's 10/100 ethernet interface is handling about 97 Mbps so I'm very happy with the throughput. After filling three tapes, we're averaging 466 GB per tape so the whole eight slot stacker will hold about 3.6 TB. Nice.
Details About Current Backups
More details to put this in the context of our environment...
Current util with dlt4000...
- first-friday-full monthly cycle
- 24 tapes/month * 32 GB/tape = 768 GB/month
- 768 GB/month * 12 months = 9216 GB/year
Util assuming we migrate to SDLT600...
- 9216 GB/year / 450 GB/tape = 21 tapes/year
- year one cost is $7400 (stacker) + $1155 (21 tapes) = $8555
- year two cost, assuming 2x increase in demand is 42 tapes = $2310
Proposed Stacker for Next Generation Backups
The Quantum SuperLoader is an eight slot stacker/library with sdlt600 or lto2 drive that goes for around $7400...
http://www.cdw.com/shop/products/default.aspx?EDC=706467
That'd give us at least 3600 GB near-line.
Our current near-line capacity is three stackers with eight slots at 30GB per slot, for a total of 720 GB. The currently monthly backup cycle is taking about 770 GB. So one SuperLoader will hold ~4.5 months of backups now, and will still hold two months of backups after our backup demands increase by 134% (3600/2/770-1).
Next Generation Backups
Our old Quantium L200 (eight slot) DLT4000 stackers are getting very long in the tooth. So I've investigated newer tape types. Executive summary: SDLT600 has the lowest "dollar/GB" value. The details can be found here... http://www.hep.wisc.edu/~rader/backup-tech.sc.txt
