how to know what non-running distros are on disks

Question

Long time ago I have installed a few Linux distros on various drives / partitions.

Now I need to know what a distro is on a specified drive / partition, without to have to boot it.

I have mounted and I can use, e.g., the directory /boot.

Earlier, a distro KNOPPIX had in this directory (or perhaps in dir with other name) a file showing the knoppix-version. Other distros don't have such a file.

From

/media/sda3/boot/grub/grub.cfg

I can read what grub would offer to boot. But this is not what I want.

vmlinux... has information about the kernel

/media/sda3/boot/vmlinuz-5.4.0-42-generic

but this is a binary.

I there a tool to extract more information than the filename says?

But this is not the name, version, release of the distribution.

How can I get that without to boot?

Answer 1

Multiple ways:

1. Run file /path/to/vmlinuz-something which will tell you the exact kernel version which you can then google to find out what the distro you're using, e.g.

$ file /boot/vmlinuz-5.16.15-201.fc35.x86_64 
/boot/vmlinuz-5.16.15-201.fc35.x86_64: Linux kernel x86 boot executable bzImage, version 5.16.15-201.fc35.x86_64 ([email protected]) #1 SMP PREEMPT Thu Mar 17 05:45:13 UTC 2022, RO-rootFS, swap_dev 0XA, Normal VGA

2. strings /bin/any_binary | grep gcc which show you a GCC release which is normally unique for a specific distro.

3. cat /etc/os-release but this doesn't always work and isn't always present.

4. Multiple files in /var/log could contain info about your distro.