Plantage eibd

[tru]

Dois-je en déduire que apache2 est lancé automatiquement en tant que root (il semble ne s'arrêter qu'avec sudo).
Le lancement sans sudo échoue, et celui avec sudo signale une erreur

Every service using a port <1024 needs to be started as root. So either use sudo or login as root. While booting all the scripts are started by the init process run under root. Most of the processes are then turned over to run with reduced priviledges with some service user id.

When working with Apache better always check the configuration first and reload it afterwards. You can do this by using the apachectl tool:
- sudo apachectl configtest
- sudo apachectl restart

The AH00558 message line is normal in the Ubuntu default configuration when reverse dns lookup for your IP-address does not return a FQDN. It's only a warning. You can omit it by adding this line somewhere (put it as last line) in the apache2.conf:
ServerName put.your.servername.here

bonne chance.
Othmar