booting trouble

[JRD]

Still don't get my answer...how is your CD drive physically connected to your computer ?

Yes it could probably be related to isolinux+grub2 that is used in MATÉ, whereas grub2 was use lonely in Xfce.

[mimosa]

Sorry JRD, I missed your question. In all three cases (one a laptop) it's an integrated drive, not an external one, connected by USB or anything like that.

[mimosa]

I can confirm that the xfce live cd works perfectly on two machines; a fresh burn of maté live fails to boot on both machines exactly as before. To repeat, I also tried Slackel earlier on. So it looks like something to do with changes to salix live after the xfce live version, that is not working properly here for some reason.

To recap, the maté live cd *does* work if the usb stick on which I attempted to put it is present. My impression is that the cd finds the relevant .live file there, but cannot find it on itself.

EDIT

There is a new thread here to continue the USB issue part of this discussion:

http://www.salixos.org/forum/viewtopic.php?f=31&t=3702

[Adys]

@mimosa,

It is unlikely that your internal CD drive on a laptop is connected using a USB port. Either it is an internal PATA, internal SATA, or external (USB or something else).

About the potential problem regarding isolinux in MATE, something is indeed strange. Let me explain.

First, gapan already said that the LIVE MATE CD is working. So we have at least one case where isolinux is correctly booting grub and then the OS from the CD.

Then there is the behavior you described: the booting procedures / precess are somehow finding the relevant info in your USB when it is also plugged in, but not when the CD is alone. IMHO, if isolinux by itself were to be the problem when booting from the CD, then the boot process would fail anyway, no matter if the file is found in the USB device or in the CD. The file you mentioned is searched after isolinux successfully boots, so if that is part of the problem, then isolinux by itself is not the problem.

Which brings us to the last consideration regarding isolinux, which is the syslinux.cfg / isolinux.cfg contents. Could you please describe when exactly the boot process fails when booting with the MATE CD? Do you get to see the boot menu? or is it failing before the boot menu? Any error messages? Do you see a "boot:" prompt either before or after the error message?

The specific error message when booting from the CD is very important, so to find out which stage is failing. If it is hardware, then it should be some error message from the BIOS. If it is isolinux, then the error message is very different and a "boot:" prompt would appear.

To help narrow down the problem, you MUST change the BIOS boot settings. Any booting device other than the CD drive should be "NONE" and the boot priority set to the CD drive as first device, and the second and following booting devices also set to NONE. Then boot with the CD alone, without any other (USB) device plugged in.

Also, do you see any SATA settings in the BIOS? AHCI settings? IDE legacy settings?

I wouldn't discard an isolinux problem yet, but we first need to confirm it is indeed isolinux that is making problems.

Please report back with details.

[mimosa]

@ Adys

It's not a BIOS problem because other Live CDs work fine, as does Salix Live xfce. These messages appear right at the beginning of the boot process, before any menu, within a second or so.

[Adys]

It's not a BIOS problem because other Live CDs work fine, as does Salix Live xfce. These messages appear right at the beginning of the boot process, before any menu, within a second or so.

When talking about booting, the BIOS is always a factor. The specific version of ISOLINUX may not support your BIOS, and an older version might work successfully (or, for example, it may be worth using ISOLINUX -> MEMDISK -> GRUB for newer versions of ISOLINUX).

Which exact messages? The exact message should give us the key info about which part / stage of isolinux is failing.

[mimosa]

Please see earlier in the thread:

http://www.salixos.org/forum/viewtopic. ... 8&start=23

EDIT

I also don't think it's a BIOS issue because the behaviour is identical on three different machines, including a spanking new Thinkpad.

[Shador]

Isolinux is not involved in this issue because he clearly gets to the grub memdisk image (which is loaded as a linux kernel by isolinux). But as an intermediate bootloader (syslinux) is used grub doesn't know which device it's loaded from. There's no way syslinux could pass that information. For that reason like the USB version the memdisk traverses all devices and looks for the .live file. For some reason it's not finding the file. One cause could be when the device containing the .live file is not accessible to the memdisk. This can be caused by the drive not being accessible through BIOS facilities due to a incompatibility between your BIOS and grub or some BIOS bug. Another possible problem is if grub's filesystem and partition code is not able to correctly interpret the data on the device or the grub modules containing the respective support are missing.

I was not involved in this recent change that requires using the memdisk for cdrom booting and the memdisk was initially not explicitly designed for that use by me. Maybe JRD can shed some more light onto this.

[Adys]

I could always be wrong, but that's after isolinux.

Code: Select all

error: "prefix" is not set
Searching the device to boot from
*Checking:(memdisk)
                (hd0)
                (hd0, msdos 8)
... 7,6,5,1 
Error: Could not find the root device!
We've been searching for:
identfile salix-mate-13.37-32.live
identcontent: [looks like an md5sum]
Available devices are (as above)
--> Rescue shell

So, if isolinux is not the problem and the system boots when the USB is connected too, my next question would be: is it really the CD what is booting and finding the relevant files in the USB device (if that is even possible in Salix MATE), or is it the USB device by itself and the CD is not really booting when the USB is plugged in?

The answer depends on the BIOS settings too, but we don't have any info about them.

It is still strange that it is failing in the same way for you in 3 different computers, while it works correctly for other users.

[Shador]

I could always be wrong, but that's after isolinux.

Exactly, that's what I was referring to.

So, if isolinux is not the problem and the system boots when the USB is connected too, my next question would be: is it really the CD what is booting and finding the relevant files in the USB device (if that is even possible in Salix MATE), or is it the USB device by itself and the CD is not really booting when the USB is plugged in?

Yes, exactly that happens if multiple devices with the exactly same live version (release + edition) are available as they have the same uuid/identcontent stored. Whatever Live installation is found first is booted. As this method is actually used another time later when the actual LiveCD boot process (initrd's init) starts running, it could even happen that you're booting from cdrom, grub is loading from usb and the live is finally running from cdrom again. Yeah, weird ...

To prevent that the .live file would need to contain a different uuid and the g2l.img would need to be updated accordingly which is not that straightforward. But it shouldn't be a problem usually anyway.