Uptime - Revision history

Jimbo at 16:34, 26 October 2007

2007-10-26T16:34:28Z

212.30.13.133: Small addition about determining real Linux uptime for the GPL fanboys.

2007-10-26T14:58:21Z

Small addition about determining real Linux uptime for the GPL fanboys.

DrModiford at 08:37, 5 October 2007

2007-10-05T08:37:47Z

DrModiford at 08:30, 5 October 2007

2007-10-05T08:30:47Z

Jimbo at 16:18, 4 October 2007

2007-10-04T16:18:24Z

DrModiford at 15:05, 4 October 2007

2007-10-04T15:05:40Z

DrModiford at 15:05, 4 October 2007

2007-10-04T15:05:14Z

Jimbo at 18:49, 28 May 2007

2007-05-28T18:49:46Z

New page

The '''uptime''' command simply writes how long it's been since the last system shutdown or reboot to [[standard output]].

break# '''uptime'''
2:49PM up 229 days, 30 mins, 2 users, load averages: 0.00, 0.00, 0.00

[[Category:System Commands]]

@@ Line 8: / Line 8: @@
 The above shows that, at 2:49pm (when the command was run), the system in question had been running for 239 days and 30 minutes.  It also had two users logged on.  The three load averages values show the system utilisation as at 1, 5 and 15 minutes ago respectively.
-Note: FreeBSD does not have an "uptime reset" issue, often referred to as the 497 day roll-over bug, that most Linux and a few UNIX and Unix-like systems do.  To determine genuine uptime on systems that are affected by the roll-over bug the following command may be of use '''last -xf /var/run/utmp runlevel'''.
+Note: FreeBSD does not have an "uptime reset" issue, often referred to as the 497 day roll-over bug, that most Linux and a few UNIX and Unix-like systems do.  (Note: to determine genuine uptime on linux systems affected by the roll-over bug, the following command may be of use: '''last -xf /var/run/utmp runlevel'''.)
 There is a project on the internet called [http://news.netcraft.com/ Netcraft] that monitors uptime of websites.  It uses the TCP/IP counter to measure uptime and as such the values are [http://uptime.netcraft.com/up/accuracy.html not always accurate].  That said, the FreeBSD (and other BSDs) are frequently topping the chart with regards to [http://uptime.netcraft.com/up/today/top.avg.html total uptime].

@@ Line 8: / Line 8: @@
 The above shows that, at 2:49pm (when the command was run), the system in question had been running for 239 days and 30 minutes.  It also had two users logged on.  The three load averages values show the system utilisation as at 1, 5 and 15 minutes ago respectively.
-Note: FreeBSD does not have an "uptime reset" issue, often referred to as the 497 day roll-over bug, that most Linux and a few UNIX and Unix-like systems do.
+Note: FreeBSD does not have an "uptime reset" issue, often referred to as the 497 day roll-over bug, that most Linux and a few UNIX and Unix-like systems do.  To determine genuine uptime on systems that are affected by the roll-over bug the following command may be of use '''last -xf /var/run/utmp runlevel'''.
 There is a project on the internet called [http://news.netcraft.com/ Netcraft] that monitors uptime of websites.  It uses the TCP/IP counter to measure uptime and as such the values are [http://uptime.netcraft.com/up/accuracy.html not always accurate].  That said, the FreeBSD (and other BSDs) are frequently topping the chart with regards to [http://uptime.netcraft.com/up/today/top.avg.html total uptime].

@@ Line 8: / Line 8: @@
 The above shows that, at 2:49pm (when the command was run), the system in question had been running for 239 days and 30 minutes.  It also had two users logged on.  The three load averages values show the system utilisation as at 1, 5 and 15 minutes ago respectively.
-Note: FreeBSD does not have an "uptime reset" issue, often referred to as the 497 day roll-over bug, that most Linux and a few UNIX and Unix-like systems do.  However the way [http://news.netcraft.com/ Netcraft] project, a site that monitors uptime of hosted websites, uses the TCP/IP counter to measure uptime and as such the values are [http://uptime.netcraft.com/up/accuracy.html not always accurate].  That said, the FreeBSD (and other BSDs) are frequently top the ranks with regards to [http://uptime.netcraft.com/up/today/top.avg.html total uptime].
+Note: FreeBSD does not have an "uptime reset" issue, often referred to as the 497 day roll-over bug, that most Linux and a few UNIX and Unix-like systems do.
 See also [[w]] command.
 [[Category:System Commands]]

@@ Line 8: / Line 8: @@
 The above shows that, at 2:49pm (when the command was run), the system in question had been running for 239 days and 30 minutes.  It also had two users logged on.  The three load averages values show the system utilisation as at 1, 5 and 15 minutes ago respectively.
-Note: FreeBSD does not have an "uptime reset" issue such as most Linux and other unixlike OSes do.
+Note: FreeBSD does not have an "uptime reset" issue, often referred to as the 497 day roll-over bug, that most Linux and a few UNIX and Unix-like systems do.  However the way [http://news.netcraft.com/ Netcraft] project, a site that monitors uptime of hosted websites, uses the TCP/IP counter to measure uptime and as such the values are [http://uptime.netcraft.com/up/accuracy.html not always accurate].  That said, the FreeBSD (and other BSDs) are frequently top the ranks with regards to [http://uptime.netcraft.com/up/today/top.avg.html total uptime].
 See also [[w]] command.
 [[Category:System Commands]]

@@ Line 8: / Line 8: @@
 The above shows that, at 2:49pm (when the command was run), the system in question had been running for 239 days and 30 minutes.  It also had two users logged on.  The three load averages values show the system utilisation as at 1, 5 and 15 minutes ago respectively.
-Note that some UNIX and Unix-like systems have a 'roll over' at 497 days where the counter it reset to zero.  This means a system with 498 days of uptime will report 0 days and so on, for each 498th day.
+Note: FreeBSD does not have an "uptime reset" issue such as most Linux and other unixlike OSes do.
 See also [[w]] command.
 [[Category:System Commands]]

@@ Line 2: / Line 2: @@
 <pre>
-break# '''uptime'''
+break# uptime
 :49PM  up 229 days, 30 mins, 2 users, load averages: 0.00, 0.00, 0.00
 </pre>