Maybe your post was split away of another thread. But it's currently missing all details.
So post the full error message that you get.
Which version of the IDE?
Which version of Fedora?
Have you tried the loop back test?
Is this an original with 16U2 ttl2usb chip or a clone with e.g. CH340 or ftdi?
Not knowing the error message makes it difficult to know what's happening. If the Arduino board has a corrupted bootloader, you can restore it by burning the bootloader; you need a second Arduino or a programmer for that (if I'm not mistaken).