Les Mikesell <lesmikesell at gmail.com> wrote: > Often it is because for the extra money, you get no extra > features except being locked into some particular vendor's > product As I have pointed out before, that depends on the vendor. Please don't blanket all vendors as the same. Some vendors have 6+ years of proven inter-product hardware RAID volume compatibility with excellent Linux support. > With software RAID1 you can pull out any single disk and > recover the data on any machine with a similar interface > type. Not always. SCSI controllers can very in their format, and even ATA can be suspect. Rare is this case, yes. But I have run into it -- especially with SCSI. > With a raid controller, if the PC or controller fails > you'll have to have exactly the same model to ever access > those drives again - Once again, I will ask you to not blanket all vendors as such. 3Ware has maintained 6+ years of inter-model volume compatibility -- far more, far better and far longer than Linux's MD/LVM which has gone through several, significant changes. This is indisputable, despite the insistance of some in the MD/LVM community -- it's more about ignorance of 3Ware than usage (or improper usage of 3Ware cards for software RAID, instead of using their hardware RAID features). > and you may or may not have the tools to observe the status > and 'smart' condition of the drives and to rebuild the > mirrors online. Any "quality" vendor has tools to not only rebuild the volume on-line, but the rebuild is done in hardware. And has many people have pointed out, the hardware can pick up where it left off regardless of any power, OS or other transient "incident." As far as monitoring tools, yes, many vendors have their own. At the same time, nearly all vendors send standard syslog messages. A few are even integrating with smartd and mdadm, and most of the reason they did not prior is because of a lack of their standardization (e.g., mdadm). Again, be careful with blanket statements. There are vendors with good track records and vendors with poor track records -- both in maintaining inter-model volume compatibility as well as Linux support. -- Bryan SIDE NOTE: It's clear to me that 3Ware's introduction of the new Escalade 9550 series with an embedded PowerPC signals that their legacy ASIC was not sufficient for DRAM and RAID-5 in the preceding Escalade 9500 series. I've said it before and I'll say it again, 3Ware Escalade 7000/8000 series products are best for RAID-0, 1 and 10, but I can't recommend the 3Ware Escalade 9000 series for RAID-5 yet (although this new Escalade 9550 looks very, very promising). -- Bryan J. Smith | Sent from Yahoo Mail mailto:b.j.smith at ieee.org | (please excuse any http://thebs413.blogspot.com/ | missing headers)