First, I’m new to Linux and Fedora. Recently I’ve made a dual boot usb and install win 8.1 and Fedora30 (i know that linux it’s more stable than windows). After installing the os… I’ve decided to upgrade the win 8.1 to 10. Now my grub looks…wird:
Try to run sudo grub2-mkconfig to reconfigure GRUB.
You will always have multiple choice for Fedora, for older kernels if a new update causes problems.
If you really don’t want them, check this topic.
You need to: open a terminal - > type sudo grub2-mkconfig and hit Enter, when the execution is finished, try to restart and see what your GRUB menu lookes like.
The sudo keyword gives the command root access, which is much like administration access in Windows.
I’ve done that…and after restart…it look’s the same. 2 fedora entrys ( fedora 30 and rescue) and 2 windows 8 (on /dev/sda1 and sdb1). I just want to have 1 fedora 30 and 1 windows 10 (i don’t have win8 anymore).
Basically, grub tries to find all the installed OSes on your computer. If, let’s say, Win8 was installed on second hard drive (sdb1 on a screenshot refers to 1st partition on the second drive), then you’ve upgraded it to Win10, and Win10 placed it’s bootloader onto a first harddrive (sda1) – then grub would find two bootloaders and correctly (from it’s point of view) list them both.
If that was one-time glitch – then @refi64’s command shall help you. @amitgold’s one was a bit incorrect, you definitely should provide grub2-mkconfig with a filename, or else it’ll just print out the new config on the screen, not save it.
If it’s persistent – then it’s very easy to rectify, but will require manually editing config files. As this post haven’t been answered for 4 days, maybe you’ve already solved your issue. But if not and you still want to do it – ping me, I’ll try to provide you with simple instructions.