I would keep it simple, and not use RAID. Most people don't understand it; especially where the risks of data loss are. At the low end, the risks of data loss are high for those who do not know a LOT about RAID. Personally, assuming this is important data, I like serial SCSI, SAS. SAS disk drives are almost always enterprise-class drives (more reliable). I would add a SAS card and connect it to an external 1.5 TB SAS drive. I might add a cheaper SATA drive (SAS controllers can do both) for older stuff. I would still use the tape backup.
Thank you, Mark Snyder -----Original Message----- I agree... the fast online data backup/ access is expensive and the slow online storage reasonable and for now the "twain shan't meet." But as long as you are looking to add retrieval speed and continue the tape bkup you referred to, and considering that hardware is relatively cheap these days, a server with a SATA RAID controller card (3ware brand?) and some drive trays full of the appropriate number of 1.5 Terra byte disks would give you the real time retrieval of your data. With the controller card, you could run RAID 5 with 4 or more drives if you like so that your system could survive & auto rebuild a drive failure (not so uncommon with large SATA drives) but you wouldn't even need RAID to as long as you have the tape backup. The key is not to invest too much labor/ money in this type of system and with the redundant tape backup you don't have to. If you drop the tape backup however ... then you are into a whole different kettle of fish. You have to have fail safe server redundancy that includes offsite dataset storage... and that is technically complex, laborious and expensive to do yourself for a real time operation... and as was noted at the start ... with commercial online services it is either expensive or slow. But you might want to do a cost analysis. By the time all is calculated, you might find it as cheap and a lot easier to not create an additional local server bkup, drop the tape backup and just contract for a commercial fast retrieval online bkup service. It also allows you to keep things simple and to remain focused on your own biz, rather than IT support. There are no magic bullets in this backup game... only various choices that have various consequences. Time, money and labor are your factors in the decision and labor is really either time or money. ************************************************************************* ** List info, subscription management, list rules, archives, privacy ** ** policy, calmness, a member map, and more at http://www.cguys.org/ ** *************************************************************************