On Feb 23, 2010, at 4:26 PM, Bruce Johnson wrote: > > On Feb 23, 2010, at 2:20 PM, Dan wrote: > >>> >>> For Data security at the cost of speed is RAID 5 across 3 disks. There is a >>> parity bit so that if one drive fails, you still can recover the data by >>> replacing the failed drive. Slower than RAID 0, but your data is secure. >> >> until the RAID card itself dies, and spazzes out on the master blocks. The >> replacement card cannot then recover things, so you've lost it all anyway. >> >> Which brings you back to Len's first query. Iffa you do RAID you gots to >> keep really good backups or risk loosing EVERYTHING. Big datacenters use >> RAID with LOTS of HDs - so they have both performance and data integrity. >> AND they also push their data off to other arrays. > > What Dan said. We run a smallish (only 3 terabytes) buncha storage here, and > have been using RAID forever. > > Contrary to what Len said RAID5 is NOT designed for data security, it is > designed for minimal downtime (If a drive fails, you can throw in a new one > and not take the raid offline while the RAID rebuilds itself.) > > Backups are your ONLY Data Security...we've experienced the very thing Dan > warns about: a RAID card goes bad and barfs all over the RAID 5. Kablooey. We > had to put in a new card and rebuild the RAID from tape, a process that took > about 32 hours at the time, and at that we lost a fair chunk of data newer > than three days old (RAID died mid-incremental backup) >
Well so then my CCC scheduled backups should do what i need? I guess mainly what I want to do is transfer files faster between drives and have every thing on one machine except for a couple of esata externals for CCCs. John Carmonne Yorba Linda USA -- You received this message because you are a member of G-Group, a group for those using G3, G4, and G5 desktop Macs - with a particular focus on Power Macs. The list FAQ is at http://lowendmac.com/lists/g-list.shtml and our netiquette guide is at http://www.lowendmac.com/lists/netiquette.shtml To post to this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/g3-5-list
