That's because the red light is actually not a gross constituent unit in a semiotic system, right?

那是因为红灯不是这一符号系统的一个主要组成单元，对吗？

The first level consists of the performance object, which is a unit that can model a physical device or abstract component in a system.

第一级包括性能对象，它是可以为物理设备建模，或者抽象系统中组件的单元。

The server unit is named after its hardware model instead of its hostname because the hostname will be specified in operating system unit.

服务器单元应该根据硬件模型名来进行命名，而不是根据它的主机名命名，因为主机名将会在操作系统单元中得到命名。