On Tue, 27 Jan 2004, Erik Dykema wrote: > Mr. Stern- > Thanks for continuing to entertain my wild conjectures :) > > The reason I'd like it to look like a hardware / removable storage > device is so that it can be recognized as such at boot time, before the > os loads. For background, I am more frequently on the debian-boot list > than on this list :) > The debian installer currently supports booting from USB > keychains, Zip Drives, CD-ROM, hard drive, etc. To my mind (apoligies > again if i use the wrong terminology), the next logical step would be to > allow one machine to boot off of 'USB storage' that one machine is > exporting to another machine. > To put it another way, if you have linux running on one machine, for > example a laptop, and want to install it on another machine, for example > a server, one way to do it is to download an installer, copy it onto a > 256mb USB keychain, then plug the keychain into the clean server, and > boot it off of the keychain.
That already seems fairly simple. > If such a device as I described in our previous messages existed (a PC > masquerading as a "USB storage device"), you could instead plug a cable > between the laptop and the server, and boot the server from the laptop. Such a thing already exists, although not in the form of a host-to-host cable. One can buy a PCI card that has the hardware for a USB device interface and install it on a PC. With the appropriate USB Gadget software loaded, that PC can then appear as a USB storage device to another machine -- using a regular USB cable! See http://www.netchip.com/linux.htm > This might allow you to, among other things, add files to the emulated > 'storage device' that the server sees, on the fly, in case you forgot a > driver or something. Um, no... That can't be done at all, whether you're using USB or anything else. If you change the structure of the filesystem on a storage device without the knowledge of the computer using that device, by adding files for instance, the filesystem will get hopelessly scrambled. The reason this sort of thing works with NFS is because NFS isn't a storage-device protocol, it's a file-sharing protocol. > Alternately, it would allow you to have an entire > OS mirror on the emulated 'storage device' so there would be no media > changes necessary during the install, etc. > It might also be interesting from the point of view that more devices > might know how to speak, out of the box the standard 'usb storage > device' protocol, while few know how to speak the whole 'usb hardware > networking + TCP/IP + NFS' protocol stack. Interestingly, not too many years ago the situation was exactly the reverse. USB didn't exist yet, but many diskless workstations had NFS built into their ROMs and could use it to boot up over a network. > Such an emulation device might have more potential applications for > both users and developers, the linux instller one is just the one that I > imangine. I rather expect that someone wanting to do this will simply buy USB device interface hardware, as described above. Alan Stern ------------------------------------------------------- The SF.Net email is sponsored by EclipseCon 2004 Premiere Conference on Open Tools Development and Integration See the breadth of Eclipse activity. February 3-5 in Anaheim, CA. http://www.eclipsecon.org/osdn _______________________________________________ [EMAIL PROTECTED] To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
