Hi,
In case you’ve a dual boot machine, sometimes it might happen that grub menu is no longer appearing.
For systems using regular BIOS, a grub-install against the device it was installed might be required, but when using UEFI, it’s really easy to use a rescue media and execute efibootmgr to alter the boot order.
When executing efibootmgr, it might output some information like this:
BootCurrent: 0001 Timeout: 0 seconds BootOrder: 0001,0019,001D,001C,0017,0018,001A,001B,001E,001F,0020,0000 Boot0000* Windows Boot Manager Boot0001* Fedora Boot0010 Setup Boot0011 Boot Menu Boot0012 Diagnostic Splash Screen Boot0013 Lenovo Diagnostics Boot0014 Startup Interrupt Menu Boot0015 Rescue and Recovery Boot0016 MEBx Hot Key Boot0017* USB CD Boot0018* USB FDD Boot0019* NVMe0 Boot001A* NVMe1 Boot001B* ATA HDD2 Boot001C* ATA HDD3 Boot001D* ATA HDD0 Boot001E* ATA HDD1 Boot001F* USB HDD Boot0020* PCI LAN Boot0021* IDER BOOT CDROM Boot0022* IDER BOOT Floppy Boot0023* ATA HDD Boot0024* ATAPI CD Note there, the BootCurrent and the BootOrder, the numbers in the BootOrder correspond to the Boot#### that are listed below it.
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