Bayard Coolidge USG said: > >>Take a PC & install a minimal Linux or *BSD on it. >>Install multiple IDE disks. >>Run software RAID on it >>Install a SCSI card in it. >> >>Now, connect via SCSI to another machine (that doesn't have IDE) & use >>it as an external RAID system. > >Well, as others have pointed out, using Target Mode is the way to go >if you *insist* on doing it this way. However, I can tell you from >personal professional experience, it ain't easy. What SCSI Host Bus >Adapters are you planning to use and does their firmware "know" >Target Mode? (Consider that a rhetorical question, BTW). How do you >(plan to) turn on Target Mode support in your SCSI Driver or your >HBA's device driver? (Assuming you know how, or it's documented...)
I'm not saying this is a good idea for a production environment. As I said in another post, I've seen something about FreeBSD being able to do this, but I haven't been able to find it. > >>>> I also don't want the traffic to go across the net. > >What net? If you have dedicated Ethernet adapters on each system and >use a crossover cable between them, it's not an issue. True. But then you're doing network access instead of SCSI access. > >>>> SCSI is *much* faster then ethernet. > >I agree with Mark Komarinski's assessment. Running 100 Mbit/sec FDX >should do the trick for you. Remember, you'll have some track/sector >seek times, so it's unlikely, in a TP environment, that you'll max out >the link for very long. Yep. 100Mb ~ 10MB (roughly). There's also some latency from software RAID. I'm also not interested in creating a Network Appliance type box. >And, since you're running a database, you want to make sure your data I'm not. I'm just putting forth an example of where an NFS'd filesystem doesn't work as well as a local filesystem. >transfers are reliable. Running with hacked-up SCSI HBA firmware and >device drivers is not, IMNSHO, commensurate with that... True. -- ------- Tom Buskey ***************************************************************** To unsubscribe from this list, send mail to [EMAIL PROTECTED] with the text 'unsubscribe gnhlug' in the message body. *****************************************************************
