Ttyjfyk

I'm thinking of dualbooting Windows 10 and Ubuntu in different partitions of the same SSD. If codes like rm -rf somehow happens in the Ubuntu partition, does this affect Windows, or does it leave other partitions alone? And if it DOES affect the Windows partition, how can I prevent this from happening?

If you have physical access to a computer, you have the power to do anything with the files on it, including reading, corrupting or deleting them.

It's possible to make it harder to accidentally delete files, though.

If you want to read documents on your Windows 10 partition, you could mount the partition in read-only mode. You won't be able to edit Word documents, but it should be enough if you want to read PDF, listen to MP3's or watch movies on your Windows partition. Another possibility would be to create a FAT32 D: partition under Windows, which you would mount with write permissions under Ubuntu.

I could think of at least 5 short commands to destroy a Windows Partition from a Linux system, but they would all require root privileges. Be careful whenever you want to run a command starting with sudo or when a program tells you that "Authentication is required to run".

Finally, be very careful when installing Ubuntu along Windows. The installer makes it clear which partitions are resized, created or deleted but it's still possible to delete existing partitions if you ignore the warnings long enough.

To be safe, please follow @Emmet's excellent advice (be sure to backup your data).

The common basic to prevent data-loss: REMEMBER TO ALWAYS TAKE BACKUP OF YOUR FILES

It doesn't affect the windows partition, because you're running it from your Ubuntu machine.

Picture it like this

/dev/sda1 ntfs-bootfile
/dev/sda2 ntfs-win
/dev/sda5 ext4-root --> (YOUR LOCATION NOW)
/dev/sda6 ext4-swap

If you run rm -rf within your location, it would affect sda5 partition—in which your Ubuntu system reside. So it only affect Ubuntu.

Supposing you have grub boot loader to load the 2 OS (Ubuntu and Windows), if you accidentally remove GRUB file aswell, Windows would not be able to boot, but the data inside will remain intact.

However, Ubuntu tend to mount Windows partition when it available, and if you say ran rm -rf /*, Ubuntu—without hesitate will delete ALL file, this include Windows partition.

There's also infamous dd command, hence the disk destroyer nickname. This is widely used to: formatting drive, cloning disk, creating bootable usb etc.

dd has ability to dump entire main drive, dd if=/dev/zero of=/dev/sda would replacing all data on main drive with zero—and goodbye to our data !

With that being said, please be very careful when running command and always take a second look before doing execute something—it's best to prevent disaster before it happens.

I highly recommend you to learn various Linux command, this way you could tell what does the command do before you ran it.

Also, again please be elaborate when working with dd, it's common mistake to mistype sdb to sda, anything happens after that is horrible.

If the fact that you can't keep two operating systems on one disk from harming one another makes you look for other solutions, here more options. They depend on your practical needs and your budget.

You can run one (or both) systems as virtual machines instead of using separate partitions. The virtual machine should have limited access to the host or other virtual machine, so you cannot accidentally damage the host machine (though there will still be deliberate ways). Another advantage is that you can use both at the same time.

If you want your two operating systems completely separate, put them on swappable hard disks or even better, separate computers (less chance to accidentally destroy your disks).

If you need to be able to access the data but very often do the kind of stuff on your Linux which can harm the Windows system accidentally with a small lapse, put them on different machines and access Windows only through a remote access tool which respects the Windows security mechanisms. You'll get full access to your data and very high security at the price of a few hundred Euro/USD for extra hardware. Additionally, you have a backup system if one fails, so if you work on these machines, the extra cost can pay off.

Risks like this can be easily mitigated by enabling BitLocker drive encryption on the Windows10 operating system. Encrypting the partition makes it for Ubuntu unable to mount and thus perform actions like rm -r

It also means that you are unable to share files with the ubuntu system via the windows partition.

If you would like to share data between the two operating systems I would advise you to create a separate data partition which you mount on both operating systems.