On 26/02/2015, Bret Busby <[email protected]> wrote: > On 25/02/2015, Simon Hobson <[email protected]> wrote: >> Bret Busby <[email protected]> wrote: >> >>> The system is completely broken, due to attempting to install an extra >>> operating system, which now appears to me, to be a trojan horse. >>> >>> The system previously had installed, MS Windows 8 (which got lost, >>> when Debian Linux was installed, but, the loss of MS Windows 8, on >>> that computer, has not been a problem, for me), Debian Linux 7.x and >>> Ubuntu Linux 14.04 LTS. >>> >>> That is the order in which the operating systems were installed, >>> before the additional one broke the system. >>> >>> When Debian Linux was added, GRUB showed only the Debian Linux OS. >>> >>> When Ubuntu Linux was added, the Ubuntu GRUB showed the boot options >>> of Ubuntu and Debian. >>> >>> When the trojan horse operating system was added, the bootloader shows >>> only the trojan horse operating system, which does not boot. >>> >>> In trying to restore the system to the state before the trojan horse >>> operating system, I have found how to get to a GRUB command line >>> prompt, which shows above specified version of GRUB as being present. >> >> Often the easiest way to fix things is to boot a live CD/USB drive close >> to >> one of the installed OSs and work from there. I know some of the Debian >> installers (everything but the "Net install ?) have an option for rescue >> and >> live modes. In Rescue mode, you can specify a partition to mount as your >> root volume, and from there you have a working system that you can use to >> repair the rest. >> >> What I'd do is : >> >> Boot from a Live CD/USB drive. >> Mount each partition one at a time and have a look at what it contains - >> a >> listing of the partitions will also tell you what type it is, if Win8 is >> still there then that should show as NTFS. If there's a /etc/fstab then >> that's a Linux/Unix root filesystem and you can see from the contents of >> the >> file what other partitions it uses. You can also look for files like >> /etc/debian_version which will give you a bit more clue as to which is >> which. >> >> Once you have identified a suitable root partition, use rescue mode to >> start >> the system and mount that as the root filesystem - actually I think it >> does >> a chroot. You can mount it's other filesystems (mount -a) and then have a >> booted system. From there, you can use update-grub and grub-install to put >> a >> working bootloader back in place. >> Whether grub shows all the other systems depends on the settings you give >> it, and/or what the distro configures it to do. From memory, I think >> Debian >> defaults to looking for others. >> >> The tricky thing with multiple OSs is managing the bootloader. By >> default, >> each one will want to install it's own. So whenever you do anything in >> Ubuntu that needs an update to the boot config, it'll do it's own thing >> and >> install the grub that's installed in Ubuntu. Similarly for Debian. And of >> course, Windows will just blow away anything it feels like ! >> >> So it may be best to remove (uninstall & purge) the grub package(s) from >> all >> but one OS. You then have to reboot into that one OS whenever your need >> to >> update grub - but you'll have a more consistent experience. >> >> The tricky one is that many installers will want to install their own by >> default - and it may or may not be difficult to persuade them not to >> screw >> up your current install. From memory, Debian does ask before installing >> grub, and it asks if you want to scan for other OSs. I have a feeling >> that >> some others, especially in "easy install" mode, may just go ahead and do >> what they like. >> >> >> PS - what was the last OS you installed that broke it ? >> > > Answer to the "PS" - PC-BSD 10.1.1 - it was supposed to be able to > allow PC-BSD to be installed into a selectable OS booting UEFI/GPT > computer system, using the GRUB bootloader, as the selectable OS > bootloader (I use the term "selectable OS booting", rather than > "multi-booting", as, to me, multi-booting means being able to boot > multiple operating systems, concurrently, which, I believe, instead, > requires virtual machines, like VMWare), and, allowing the person > performing the installation, to select into which GPT partition, > PC-BSD would be installed, but, instead, it has wrecked the computer > system, rendering the system unusable without either restoring GRUB, > if that can successfully be done (which appears increasingly > doubtful), or, a complete system rebuild, involving re-installing each > of the operating systems that was previously installed (which excludes > MSWin8, as no installation media, were provided with the computer). > PC-BSD 10.1.1 is dangerous, and, to me, a trojan horse thing. > > I had gone into the rescue mode, using a Debian 7.8 install iso image, > and got to a screen that said something like "Into which of the > following partitions do you want to install the root partition?", and > it listed the 13 GPT partitions, in the format of something like > /dev/sda<x> . > > But, it did not show which were the OS partitions (one for each of > MSWin8, Debian 7, and Ubuntu 14.04 LTS). > > In trying to use the GRUb command line to which I had referred, I > hoped to try to find which of the partitions were the OS partitions, > so as to hopefully be able to restore the GRUB bootlaoder, and be able > to boot one of the bootable operating systems. > > In trying to find whether I could save the sequence of command line > commands and the respective response outputs, I had hoped to be able > to, using a USB thumbdrive, examine the information on a usable > computer, and figure out what to do next. > > At present, I do not know which partitions are the appropriate > partitions into which to install root systems, so I am unable to use > the rescue mode -> restore grub process. > > It took me about an hour, to get the system to provide me with the > information for me to (and, including my doing it, to) write down the > information that I believe to be the relevant information from the > GRUB >> ls (hd0, gpt<x>) > commands for each of the partitions. > > Then, the next day that I have the time to do it, I expect that it > will take me another hour or two, to obtain and write down the > information from the GRUB >> ls (hd0, gpt<x>)/ > commands for each of the partitions, to try to establish what is each > partition. > > It may be another week, before I can allocate that time > > The GRUB ls commands appear to not show partition labels for the non > PC-BSD OS partitions, even though they should have labels (unless the > OS partition labels have been stripped by the PC-BSD installation > procedure, in addition to the other damage that it has done to the > system), > > From a response that I have seen on another mailing list, to my query, > the GRUB command line does not provide for mounting a USB thumb drive, > then writing all commands and responses, from a start point to an end > point, to a file to be saved on the USB thumb drive, then to unmount > the USB thumbdrive, which would otherwise allow the commands and > responses, to be examined as wanted, on an operable system, without > having to boot the now inoperable system, into the GRUB command line > mode (which appears to be all that works, now, on that computer), to > rerun the commands, each time that I want to re-examine the commands > and the responses. > > That is unfortunate, as the functionality that I want, would be quite > helpful, if it would be available. > > >
Hello. I have attached a copy of what I believe to be the last usable version of the grub.cfg file, which I hope will be successfully transmitted as an attachment. If not, I will try to send it inline, within a further message. I have found that file, using the file manager in a Debian 7.60 LXDE amd64 LiveCD. That does not tell me (that I can interpret), in which partition, the file sits, due to the use of the meaningless and obscurantist UUID system of partition descriptors, rather than the meaningful partition number system ( (hd<x>, gpt<y>) in the PC-BSD UEFI/GPT system, or /dev/sda<y> in the more meaningful (than UUID) Debian v <n<=6> systems) but, I assume, by context, the following. The grub.cfg file and the Ubuntu installation, are in partition 12. The Debian installation is/was in partition 6 (it appears to be not visible to the Debian 7.6 LiveCD). Now, the question becomes, given that the now disabled/overridden GRUB bootloader has apparently been located in the Ubuntu installation in (apparently) partition 12 of the HDD, how do I disable the BSD bootloader and re-enable the GRUB bootloader that is apparently in partition 12 on the HDD? I understand that a Debian 7.8 installation CD, in the rescue mode, has the option "Device to use as root file system", which, I assume would restore the functionality of the GRUB bootloader, if it was in the Debian installation, but, the last properly functioning GRUB bootloader is in the Ubuntu installation, and I am not confident that the Debian software, if used to operate on the Ubuntu system, would not interfere with the (previous to the sabotage by PC-BSD) functionality of the Ubuntu installation, and the Ubuntu 14.04 LTS dik that I have, appears to not have an equivalent of the rescue mode of the Debian installation CD. Thank you in anticipation, for any constructive and helpful advice that solves the problem. -- Bret Busby Armadale West Australia .............. "So once you do know what the question actually is, you'll know what the answer means." - Deep Thought, Chapter 28 of Book 1 of "The Hitchhiker's Guide to the Galaxy: A Trilogy In Four Parts", written by Douglas Adams, published by Pan Books, 1992 ....................................................
grub.cfg
Description: Binary data
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