有段说明文字:
# Default runlevel. The runlevels used by RHS are:
# 0 - halt (Do NOT set initdefault to this)
# 1 - Single user mode-------单用户模式
# 2 - Multiuser, without NFS (The same as 3, if you do not have networking)--不带网络服务的文字界面
# 3 - Full multiuser mode-------------文字界面带网络服务的,一般都是这个除非是单机
# 4 - unused
# 5 - X11------------就是图形
# 6 - reboot (Do NOT set initdefault to this) id:5:initdefault: