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