Linux uptime command is a simple command used to display how many times ago the computer or server restarted. Uptime command provides following information too;
- Current Time
- How lon the system has been running
- How may users currently logged in
- System avarage load in last 1, 5, 15 minutes
Show Uptime
We can show uptime like below.
$ uptime

This command will list total number of time of uptime in days and hours. There is also information like currently logged in user count and average CPU load.
Show Pretty Format
If we want to know relative date format and more human readable format we can use --pretty
option like below.
$ uptime --pretty
Show Uptime Relative To Given Date
We can show uptime to the relative to a given date. This will show since this date.
$ uptime --since 2017-03-29 00:00:00