91 lines
2.9 KiB
Markdown
91 lines
2.9 KiB
Markdown
# Broken Machines
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Over the coarse of my Linux career I broke quite a few machines.
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Hopefully you can fix these for me.
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The username and password of the first account created is isib/isib unless mentioned in the exercise.
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## GRUB problems
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### Broken Machine 1
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I messed up and forgot to install grub during the Debian installation.
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Can you find a way to fix this for me please?
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Thanks!
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
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#### Tips
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How did this happen?
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Well, you probably encountered the *black screen of death* on one or more Linux VM's yourself.
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When at the very last stage of the Debian installation you forget to install GRUB you created this problem yourself.
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The installation is complete and functional but the system has no way of booting.
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There are a lot of different approaches to fix this but they all boil down to the same solution.
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You need to install GRUB on the MBR of the HDD `/dev/sda`.
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Luckily there are dedicated live disk images (ISO's) to fix this.
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I would recommend having a look at [supergrub2](https://www.supergrubdisk.org/).
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### Broken Machine 2
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This machine seems to boot into `htop` and nothing else!
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There must be a way to fix this without having to reinstall the machine.
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
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#### Tips
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Your GRUB configuration is causing this!
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Luckily by default GRUB offers a *recovery mode* in it's *advanced options*.
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This will drop you into a shell where you can fix the configuration file I messed up.
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### Broken Machine 3
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Not `htop` again!
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
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#### Tips
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I said *by default* before no?
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Well, here the *recovery mode* is missing so you'll have to find a way to override the `init` parameter of GRUB so you can get a shell to fix what I messed up.
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### Broken Machine 4
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I forgot my password...
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
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#### Tips
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Overriding the `init` parameter in GRUB is a classic Linux hack.
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If you have physical access to a Linux machine you can gain `root` access with the following method.
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The easiest way to protect a machine form this attack is to do full disk encryption or to set a GRUB password.
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## Disks and problems
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### Broken Machine 5
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Somebody erased the MBR from the HDD.
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Can you put a new one on there?
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Don't forget to install GRUB again once the HDD is fixed.
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This is a tricky one but there are quite a few tutorials online to help you out.
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
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### Broken Machine 6
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The root partition is pretty much full but the disk is big enough to house more data.
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Can you please enlarge the disk so we can comfortably use the machine again without running into `no space left on device` issues?
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
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### Broken Machine 7
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The install works but the root partion is rediculously small.
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Luckily the installation was done on a LVM volume so we can add more disks to it!
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
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