sudo find /etc | xargs grep -i fedora > searchFedora
gives:
/etc/netplug.d/netplug: # At least on Fedora Core 1
...
But see the Fedora version in the /etc/netplug.d/netplug
file. Is it serious?
cat /etc/issue
Or cat /etc/fedora-release
as suggested by @Bruce ONeel