Merci pour la commande que je ne connaissais pas,
Voilà ce que ça me renvoie :

Forbidden

You don't have permission to access / on this server.
Apache/2.0.54 (Fedora) Server at localhost Port 80

toujours pas d'accès

avant, il ya ceci :
[root@localhost ~]# firefox 'http://localhost' &
[1] 5920
[root@localhost ~]#
(firefox-bin:5949): Gdk-WARNING **: gdk_property_get(): length value has wrapped in calculation (did you pass G_MAXLONG?)
*** nsExtensionManager::_disableObsoleteExtensions - failure, catching exception so finalize window can close
*** loading the extensions datasource

(firefox-bin:5949): Gdk-WARNING **: gdk_property_get(): length value has wrapped in calculation (did you pass G_MAXLONG?)
*** loading the extensions datasource
UA: Mozilla/5.0 (X11; U; Linux i686; fr; rv:1.7.12) Gecko/20050922 Fedora/1.0.7-1.1.fc4 Firefox/1.0.7:, extra: Firefox/1.0.7