Svartalf
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Re: Boot loader for USB devices

Wed Aug 31, 2011 3:16 am

Quote from mvb on August 30, 2011, 20:36
Sorry! Me culpa! Is there any gadget with which I can boot via Ethernet?


This one, really- it just requires a bit more efforts on the part of the person trying to do it. If you have a pre-specified initramfs in your kernel or specify one on a small SD card, you can just leave that pretty much alone. Inside the initramfs, you init the USB Ethernet/Wireless and then mount your filesystem. From there, you pivotroot into the mount accordingly.

In truth, you can craft something that works better than things like PXE and bootp with a bit of effort.

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ukscone
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Re: Boot loader for USB devices

Wed Aug 31, 2011 3:23 am

yes an initramfs with pretty much just busybox in it would do.

mvb
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Re: Boot loader for USB devices

Thu Sep 01, 2011 5:45 pm

... If you have a pre-specified initramfs in your kernel...
Yes, I could use any root file system I like with that. But I want to load an arbitrary kernel.....

Svartalf
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Re: Boot loader for USB devices

Thu Sep 01, 2011 5:56 pm

Quote from mvb on September 1, 2011, 18:45
... If you have a pre-specified initramfs in your kernel...
Yes, I could use any root file system I like with that. But I want to load an arbitrary kernel.....


Then you're not going to get network rootfs. The functionality has been pretty much removed from the later on 2.6 kernels. I know this because we had issues trying to use the vanilla 2.6 kernels with our ATCA stuff under Montavista Linux- they've been porting it back in for the last 2-3 years now to their kernels. You have to have the embedded initramfs, or supply one with your arbitrary kernel, do your network mount and pivotroot into it.

mvb
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Joined: Sat Aug 27, 2011 2:48 pm

Re: Boot loader for USB devices

Thu Sep 01, 2011 6:30 pm


Then you're not going to get network rootfs. The functionality has been pretty much removed from the later on 2.6 kernels. I know this because we had issues trying to use the vanilla 2.6 kernels with our ATCA stuff under Montavista Linux- they've been porting it back in for the last 2-3 years now to their kernels. You have to have the embedded initramfs, or supply one with your arbitrary kernel, do your network mount and pivotroot into it.

What do you mean by that? Why can't I load ramfs from network while booting?
At my job I'm currently using several x86 and some older PPC servers with 2.6 kernel. They all can boot from network and have their rootfs on a NAS.
Though it is crucial to specify the version of NFS used, like in
nfsroot=192.168.42.42:/shrike/ppc/van26d10,v3
kernel.org's howto is your friend http://www.kernel.org/pub/linu.....-howto.txt

alexleung
Posts: 2
Joined: Fri Sep 16, 2011 3:20 pm

Re: Boot loader for USB devices

Fri Sep 16, 2011 4:59 pm

GRUB support USB bootup!

I install Ubuntu 10.04 & Ubuntu 10.10 on SDHC card.

Because SDHC is very slow to write a lot of file. Actually, using desktop computer finish installation ubuntu in XFS format parition HDD. Then, using xfsdump and xfsrestore to clone to SDHC.

Svartalf
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Joined: Fri Jul 29, 2011 6:50 pm

Re: Boot loader for USB devices

Fri Sep 16, 2011 5:35 pm

Quote from alexleung on September 16, 2011, 17:59
GRUB support USB bootup!

I install Ubuntu 10.04 & Ubuntu 10.10 on SDHC card.

Because SDHC is very slow to write a lot of file. Actually, using desktop computer finish installation ubuntu in XFS format parition HDD. Then, using xfsdump and xfsrestore to clone to SDHC.

GRUB's not designed with ARM devices in mind. Typically you see RedBoot, U-Boot or similar on an ARM Linux based device.

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