Daemons and services

1. Definition of daemons

Daemons is translated as a daemon. It refers to a program running in the background that provides a function. In other words, it is a service. Therefore, daemons is a background process that provides services in the resident memory.

2. Daemons Classification

By startup:

Stand_aloneCorresponding to the/etc/init. d directory

It is called an independent process. It is started upon startup and remains active. It occupies system resources and can quickly provide services. For example, WWW Service

Super_aloneServices managed by xinetd

Managed by a unified process (for example, xinet), wake up the corresponding process when xinet listens to the request. For example, FTP service

By status:

Singnal-control

Excitation by signal, such as printer

Interval-control

Timed excitation, such as Cron

3. Daemons (service) Port Number

/Etc/services

So much for the time being, and try again later.