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Firewire and Linux?
aozilla asks: "I was just at Pricewatch, and I noticed that 80 gig firewire drives are available for only $200. My good old IBM Deskstar just crashed, so I'm in the market for a new hard drive, and I'd love to go with Firewire. External, hot-swappable and the ability to have more than 2 devices without significant slowdown are the main features I'd like on top of what I get from my IDE drives. I'd like to hear from those who have experience running firewire on Linux. How good is the driver support? Is hot-swappability really supported (just umount and unplug, plug and mount)? Are there any recommendations for PCI Firewire cards for Linux? How many drives can reasonably fit before power becomes an issue (I assume the less expensive drives obtain power from the port)? My main goals are capacity, cost, and convenience. Speed is not too much of an issue, and I'm more a fan of automated and explicit backups rather than RAID."
If the controller card's bios allows it to boot, then there's tricks you can manage. Back when I began my shift over to SCSI, in '96, I had a 1gb IDE and a 2gb SCSI-2 drive. My bios didn't support boot from scsi and I ran NT/95. Since I wanted to keep the two seperated and run multiple OSes, I realized I could simply turn off the IDE controller in the bios. I thus booted from SCSI, loaded NT, and had full access to my IDE drive since (like Linux?) it ignores/by-passes the bios. If I wanted '95, turn it on. No problem.
If he has IDE and Firewire components, and runs a modern OS, then he could do the same thing. Turn off the IDE controllers (perhaps just the one with the harddrive, not CDROM/DVD so he can boot from them). The firewire card's bios thus boots the drive, the OS detects the IDE components, and he's cool.
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I think firewire is cool as hell, but not for this application. It's got bandwidth galore, to move video data back and forth, but this doesn't translate to "bandwidth galore for storage".
Why not? Are the seek times more? What are the practical problems with firewire vs. IDE?
Hot plugability is an issue? How many times will you actually use this?
Four times a day, Monday through Friday, at the very least. Sharing with 2 PCs... I'd also use it for backup purposes if it really worked well. Why bother with tape backups when I can spend $200 and back up 80 gigs?
If speed isn't an issue, what's wrong with IDE?
As I said, hot swappability, and the ability to add more than two devices without a significant speed detriment (and the ability to add more than 3 HDs at all, besides my CD-rom).
Another advantage is that I won't have to spend 2 hours installing the drives in my parents' computers when I give the old drives to them and buy new ones.
Or even external scsi? A decent scsi card, and external drive are no more expensive than the 1384 drives I've seen. There are plenty of dumb/slow/external drive solutions, and in every case they're cheaper than firewire.
My rough estimate would be $250x3 for 3 80 gig drives, plus $100 for the 1384 card. What hot swappable reasonably fast (no tape drives) solution do you know of for $850 for 240 gigs?
ok then your [sic] infringing on my copyright! Could you as [sic] me next time before STEALING my comments for your own?
When you dig down into the SBP-2 layer of IEEE-1394 you will find that it is SCSI. SCSI commands and responses are used for the mass storage device on IEEE-1394. The only thing that is different is the physical and low level signal transmission. So, at the software level (once you get above the lowest level packet sender/receiver) there is no difference from scsi.
:-) A 12% cost savings will win in the end.
At the physical level you get to trade a 50 or 68 pin connector and cable for a 6 or 4 pin connector and cable. The controller chips probably cost about the same in volume, maybe a couple of bucks different. A good SCSI cable (and don't mess with bad ones) is $50. A good firewire cable is $7.
There is your reason. A $300 disk is $350 with
SCSI and $308 with Firewire. (I added a dollar for the $0.50 license fee on the ports at each end of the cable.
Non-tangibles such as easy configuration, the ability to pile a dump truck load of disks on a single interface, and not becoming ensnared in a wriggling mass of cables are just nice bonuses.
(I have used SCSI for ages, but now prefer IEEE-1394 for my archival storage machines. I still use SCSI for my high reliability and high performance machines, but that is more a Linux driver issue than anything intrinsically IEEE-1394.)
I love how you state "I'm more a fan of automated and explicit backups rather than RAID"
RAID isn't for backups and shouldn't be thought of as such. its for performance and reliability. a RAIDed server can remain functional with a dead harddrive. A non-RAIDed one cannot. A RAIDed server can see a performance boost from the ability to read from whichever drive happens to be free. Backups should be done in any event, not instead of.
Of course, I assume you're talking about a desktop, in which RAID is only really nice for having a really large disk or for performance if you're a graphic artist
First, Firewire == Apple-branded 1394. IEEE 1394 is an IEEE spec, it has nothing to do with IBM.
Second, 1394 specifies both powered and unpowered connectors/cables. Powered is far more common. You'll see the unpowered connectors on cameras and Vaios. They're small and break off in the port.
Most devices use the powered connectors, even if they don't draw any juice. A wall-wart is always safer, since you may be sharing the power with other devices: good for recharging (iPod); bad for a reliable hard drive (but very convenient with a laptop..)