I'd like to find out how long the system has been running under UNIX or Linux operating system. How do I find out system uptime?
Both Linux and UNIX like systems comes with various command to find out server uptime command. Under Linux file /proc/uptime has uptime information and file /var/run/utmp has information about who is currently logged on. However, information from /proc or utmp file is not directly readable by humans so you need to use the following commands.
UNIX / Linux uptime command
Open a command-line terminal (select Applications > Accessories > Terminal), and then type the following commands:
21:54:11 up 13 days, 4:29, 1 user, load average: 0.21, 0.21, 0.12
The uptime command gives a one line display of the following information.
- The current time (21:54:11)
- How long the system has been running (up 13 days)
- How many users are currently logged on (1 user)
- The system load averages for the past 1, 5, and 15 minutes (0.21, 0.21, 0.12)
This is the same information contained in the header line displayed by the w and top commands:
21:56:06 up 13 days, 4:31, 1 user, load average: 0.03, 0.14, 0.09 USER TTY FROM LOGIN@ IDLE JCPU PCPU WHAT root pts/0 123.xxx.yy.zzz 21:54 0.00s 0.02s 0.00s vi
Please note that the w command displays who is logged on and what they are doing while top command provides a dynamic real-time view of a running Linux/UNIX/BSD operating systems.