booting trouble

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JRD
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Re: booting trouble

Post by JRD »

Former Live version uses grub2 directly, not isolinux. So building a new ISO using another isolinux version is irrelevant here.
At my opinion, the problem here is that the image is an isohybrid image. I could try to procude a iso without that technique to see if it helps.
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Adys
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Re: booting trouble

Post by Adys »

JRD wrote:At my opinion, the problem here is that the image is an isohybrid image. I could try to procude a iso without that technique to see if it helps.
In that case, mimosa could expand the ISO, delete "[BOOT]", and rebuild the ISO with isolinux.bin from Syslinux. You only need to provide the mkisofs command line parameters for him to reproduce it. The new ISO won't include isohybrid.
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JRD
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Re: booting trouble

Post by JRD »

Well. To suppress isohybrid it's easier :

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dd if=/dev/zero of=salixlive-mate.iso bs=2k count=16 conv=notrunc
Could you please such a ISO/CD please ?
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Shador
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Re: booting trouble

Post by Shador »

JRD wrote:Well. To suppress isohybrid it's easier :

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dd if=/dev/zero of=salixlive-mate.iso bs=2k count=16 conv=notrunc
Could you please such a ISO/CD please ?
But does that get rid of isolinux or just isohybrid?
JRD wrote:Shador, could you look at it? My german is poor and the translation (by google & co) is hard to understand.
It's not saying much anyway. To my understanding it does exactly the same isohybrid does except it adds the MBR code needed to load the core.img instead of isolinux.
Anyway, I guess that's a better option than using isolinux + isohybrid.
mimosa wrote:The output of ls is the same as posted previously.
To me it's not absolutely clear how that paste is meant. But nevermind
JRD wrote:But do memdisk can boot linux kernel ? Because g2l.img is a kind of linux kernel (in the signature at least). It cannot boot grub2 core.img for sure.
No, but it could work when prepending diskboot.img instead of lnxboot.img to the core.img.

One could also experiment with other intermediate bootloaders (lilo/???). Or loading a core.img with blocklists directly which needs grub-bios-setup. Scanning for the boot device would be unneeded then
grub-mkstandalone available as of 2.00 is an interesting option too but could make the core/g2l.img too big.
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JRD
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Re: booting trouble

Post by JRD »

Shador wrote:But does that get rid of isolinux or just isohybrid?
Just Isohybrid.
Shador wrote:It's not saying much anyway. To my understanding it does exactly the same isohybrid does except it adds the MBR code needed to load the core.img instead of isolinux.
Anyway, I guess that's a better option than using isolinux + isohybrid.
Yes I figure it out reading the perl code (and reading perl documentation because I'm not a perl guru) and reading the sh script for it's distribution.
About better than isolinux, I think it's quite the same, except we will need core.img on the CD. So if anyone wants to install this on a USB key without using isohybrid, he will not have the choice to use syslinux or another bootloader. He will need to install grub2 on that disk and that will lead to the same exact problems we had before. Chainloading to grub2 is a better option (from syslinux, isolinux, lilo, whatever) in my opinion.
Shador wrote:No, but it could work when prepending diskboot.img instead of lnxboot.img to the core.img.
Ok I understand. But that could make things more complicate, and the ISO size bigger.
Shador wrote:One could also experiment with other intermediate bootloaders (lilo/???). Or loading a core.img with blocklists directly which needs grub-bios-setup. Scanning for the boot device would be unneeded then
grub-mkstandalone available as of 2.00 is an interesting option too but could make the core/g2l.img too big.
Good idea. About grub-mkstandalone, I haven't seen it yet.

xorriso seems to do a better job than the job done by syslinux team, especially not starting the hidden partition at sector 0. The only problem is that it doesn't boot on some MacOS X hardware without removing the isohybrid header like I quote above. Not a big deal for me.
But let's confirm that the problem is isohybrid here. If it's something else, then no need to do some magic about the bootloader.
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Adys
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Re: booting trouble

Post by Adys »

JRD wrote:
Shador wrote:But does that get rid of isolinux or just isohybrid?
Just Isohybrid.
@JRD,

That was my point exactly, to replace isolinux.bin with a "clean" file from syslinux v.4.05 or from syslinux v3.84; not just the isohybrid boot record.

Deleting the first 16 x 2048 sectors of the ISO should work, but the whole point here is to find out what exactly is different in all 3 mimosas's computers, so I was trying to be more thorough. The problem here is what "should" work against what it is "actually" working.

I'm not even convinced that the problem is isohybrid. The CD device boots. The error mimosa sees presents itself after isolinux, and - at least in theory - isohybrid is not part of the CD booting process (isolinux.bin is). If I understand the error message correctly, the "live" file is not being found since the root of the device (the CD itself) is not detected during the grub stages (or at least after isolinux). Instead of the CD, mimosa's system founds only hd0. If the USB is connected, it founds hd0 AND the USB device, where it finds the "live" file, so it can continue booting (I'm not sure if it continues the booting process from the CD or from the USB where the "live" file was found).

Let's wait for mimosa's input and BIOS+hardware specific info.
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JRD
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Re: booting trouble

Post by JRD »

I'm not convinced.
Isolinux works, no need to make a new version of it.
The problem is that grub2 does not "see" the CD. The CD is exposed by the BIOS. If the BIOS is puzzled by the IsoHybrid format and will not export the CD, then this is the problem.
zeroing the first 32KB is easy and can help find the problem. Building a new iso, is in my opinion, not a way to go.

In fact you said it boots the "CD", but we don't know it actually. We know it boots from data on the CD, but not necessary the Et Torito thing. Perhaps it sees it as an hard disk (because of IsoHybrid) and boot using its MBR, rather than the Boot Catalog of the CD. I first want to be sure how it boots.
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mimosa
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Re: booting trouble

Post by mimosa »

I'm afraid the discussion has got a little over my head, but I'm happy to do any tests as time allows.

It seems worth asking: has *anybody* else reading this discussion had the same problem? Does anyone have a Thinkpad at home? (I mention that because it's easy to identify - I'm not altogether sure what the other two are.) People tend not to use CDs any more given the option of booting from a stick - I only did so because mine wasn't working (see other thread).

@ Shador, those devices are the hard disk and its partitions, like this:

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memdisk
hd0
hd0, msdos 8
hd0, msdos 7
hd0, msdos 6
hd0, msdos 5
hd0, msdos 1
Compare the output of fdisk -l:

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Disk /dev/sda: 60.0 GB, 60021399040 bytes
255 heads, 63 sectors/track, 7297 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x000664eb

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *           1        1402    11261533+   7  HPFS/NTFS
/dev/sda2            1403        7295    47335522+   f  W95 Ext'd (LBA)
/dev/sda5            1403        4589    25599546    b  W95 FAT32
/dev/sda6            4590        6413    14651248+  83  Linux
/dev/sda7            6414        7173     6104668+  83  Linux
/dev/sda8            7174        7295      979933+  82  Linux swap
Adys
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Re: booting trouble

Post by Adys »

@mimosa,

Could you please provide info about your BIOS and its settings? For example...

Is there any one of those computers using UEFI instead of a traditional BIOS?

In the BIOS, could you set your local HDD as NONE and not to be automatically searched at boot?

Are you using a PATA HDD? Is your optical drive PATA? Are those connected in the same PATA port (primary master and slave; or secondary master and slave)?

Do you have any AHCI BIOS setting? Or any IDE compatible mode BIOS setting?

Which devices the BIOS "sees" as first / second / third / ... / boot devices?

Could you disable the USB settings in your BIOS?

For any changes, write down the original setting before performing any change.

Or maybe these questions are "too much"?

What about the dd code posted by JRD (the one with bs=2k)? Is that possible?
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mimosa
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Re: booting trouble

Post by mimosa »

@ Adys
They're all very ordinary BIOSs as far as I can see (not UEFI) giving you the usual control over which device to boot from. The main apparent difference is the structure of the menus and which keys you press to get at the thing in the first place. To be more specific than that would require quite a lot of work with a notebook and repeated reboots. I've spent quite some time fiddling with the BIOS (in my earlier distro-hopping days), and these ones look pretty typical to me. I don't know whether they have some of the specific features you mention, but anyway, nothing that I've turned on.

And except for the Thinkpad, both other machines have seen a lot of use with one distro or another - I took a while to convert to USB booting live Cds. Only recent Salix live cds have shown this behaviour.

There must be someone out there with a Thinkpad who could try and reproduce this :)

@JRD
I can certainly try zapping the beginning of the iso and burning and booting, as Adys suggests, if you like?
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