Thanks to you and Kyle for the hint on rootdelay, I will give it a try. Regarding the performance, it should not be a real issue in my case. I will only use the key to boot the kernel and send a Wake-on-Lan packet to a file server, then I'll mount the discs over NFS.
bye, raf On Wed, 2008-04-30 at 08:56 +0200, Branko Badrljica wrote: > I had the same two problems. > > WRT to grub, I don't remember anymore exactly what I have done, but I > think I have > copied sectors 1-62 from one conventional grub-bootable HDD to USB, > > Or maybe used some old HDD and formated it, parittioned it like the USB > disk, copied /boot partition on it and set up grub on it, then copied > sectors 1-62 back to USB disk. > Sector 0 is for MBR codeand last few tens of bytes contain headers for > first 4 partitions, so it shouldn't be touched and first partition > begins with sector 63. > > Something like that. > > > WRT to boot panics, kernel can't find USB key at boot since USB > initialisation code needs more time for key to stabilise. Use kernel > parameter rootdelay=10 for 10 second wait period for USB > > Hope this helps. > > > BTW: You will in all likelyhood be dissapointed with USB key > performance. Its R/W throughput is comparable to HDD only on paper. In > reality it seems that USB can't cope efficiently with small sector-sized > writes but also scattered reads seem to be far from optimal.Either that > or USB driver really sucks on Linux. > > It is very useable as fallback though. Like having one USB key soldered > directly on the MoBO and using it for boot if/when your HDD croaks or if > something eats your main boot option... > > > Regards, > > > Branko > > > > > Raffaele BELARDI wrote: > > In the process of building an amd64 diskless box, I am trying to make a > > bootable USB key with no success up to now. > > > > The first problem I encountered was related to ext2/vfat. I initially > > tried to format the key as ext2, but grub refuses to install on it. Even > > though I copied the /boot/grub/* directory into the key, and I see it is > > there, grub does not see it. The problem does not happen with vfat. > > > > So I worked around that and created two partitions in the key, a small > > vfat for the /boot and a 2Gb ext2 for the /. I copied the stage3 into > > the / with no problem. In the /boot I put the kernel image which I am > > already using on the same box, for now with discs still connected. All > > the modules are compiled in. > > > > When I boot from the key, grub enters the shell (although I did create > > the grub.conf and menu.1st, so I don't understand why it doesn't show > > the menu). I manually specify the kernel file location and root > > parameter: > > > > > >> kernel /linux-2.6.24-gentoo-r4 root=/dev/sdg1 > >> boot > >> > > > > The kernel starts to load, but panics because it is unable to find the > > root partition. When it stops it shows the available partitions, these > > include all the hard disk partitions but no USB key partition. In fact, > > if I omit the 'root' parameter from the grub shell the boot works fine > > but it uses the hard disk root partition instead of the USB one. > > > > >From the log on the screen the USB controller seems correctly detected, > > so I don't understand why it is not finding the root. While writing this > > one idea comes to my mind, maybe it is failing because I attach the key > > to a SDC/MMC/USB card reader? This evening I'll try to plug it into a > > different USB slot. > > > > Any other ideas welcome. > > > > raffaele > > > > > -- [email protected] mailing list
