réinstaller interface graphique debian

Shell
> tasksel --list-tasks
i desktop       Graphical desktop environment
u web-server    Web server
u print-server  Print server
u dns-server    DNS server
u file-server   File server
u mail-server   Mail server
u database-server       SQL database
u ssh-server    SSH server
u laptop        Laptop
u manual        manual package selection
Source

Also in Shell: