Linux/System Monitoring - Revision history

Admin: /* Rotating logs */

2016-03-14T04:27:40Z

Rotating logs

← Older revision		Revision as of 04:27, 14 March 2016
Line 238:		Line 238:
	to rotate logs, use <code>logrotate</code>		to rotate logs, use <code>logrotate</code>

			To rotate logs for the apt process, for example, edit the file <code>/etc/logrotate.d/apt</code>:

			<pre>
			/var/log/apt/term.log {
			rotate 12
			monthly
			compress
			missingok
			notifempty
			}

			/var/log/apt/history.log {
			rotate 12
			monthly
			compress
			missingok
			notifempty
			}
			</pre>

			This handles two different log files. This will backup up to 12 backup files, which will be rotated monthly (the monthly option). The compress option will compress (potentially very fat) log files.

	=Related=		=Related=

Admin: /* Related */

2016-03-14T04:17:13Z

@@ Line 211: / Line 211: @@
 $ ncdu -x /home/joecool/
 </pre>
 =Related=

Admin: /* Shell Monitoring */

2016-03-14T04:01:44Z

Shell Monitoring

← Older revision		Revision as of 04:01, 14 March 2016
Line 169:		Line 169:

	[[Image:Htop.png\|500px]]		[[Image:Htop.png\|500px]]



			==Storage==

			To monitor storage, use the <code>du</code> and <code>df</code> commands.

			Both commands should be paired with the <code>-h</code> flag, for Human-readable (MB or GB file units):

			<pre>
			$ df -h
			</pre>

			This shows free space on all mounted file systems.

			The du command gives a directory-level picture of the file system usage. you can run it like this:

			<pre>
			$ du -hs directory/
			</pre>

			s shows a Summary (only the total) and h makes it Human-readable.

			===ncdu===

			The ncdu command is a very nice way to get a more detailed overview of disk usage in a particular directory. it is a pseudo-graphical interface on the terminal that presents an easy to understand summary of information about what directories use the most space.

			<pre>
			$ ncdu /
			</pre>

			will show you a breakdown of your entire filesystem. You can also look at just a particular directory:

			<pre>
			$ ncdu /home/joecool/pictures
			</pre>

			If you don't want it to scan external mounts, which can swamp a network connection and take forever with large network drives, use the -x option:

			<pre>
			$ ncdu -x /home/joecool/
			</pre>

	=Related=		=Related=

Admin: Admin moved page Linux/Network Monitoring to Linux/System Monitoring

2016-03-14T03:53:11Z

Admin moved page Linux/Network Monitoring to Linux/System Monitoring

← Older revision	Revision as of 03:53, 14 March 2016
(No difference)

Admin: /* htop */

2016-03-14T03:52:29Z

htop

← Older revision		Revision as of 03:52, 14 March 2016
Line 164:		Line 164:


	===htop===		===htop===

	htop is a fancy version of top.		htop is a fancy version of top.

	[[Image:Htop.png]\|500px]]		[[Image:Htop.png\|500px]]

	=Related=		=Related=

Admin: /* Shell Monitoring */

2016-03-14T03:51:49Z

Shell Monitoring

@@ Line 124: / Line 124: @@
 <pre>
-$ apt-get insall htop iotop ncdu
+$ apt-get install iotop ncdu htop
 </pre>
 =Related=

Admin: /* Memory Load */

2016-03-14T03:44:52Z

Memory Load

← Older revision		Revision as of 03:44, 14 March 2016
Line 115:		Line 115:

	This memory amount is much larger, because it considers the disk cache flexible.		This memory amount is much larger, because it considers the disk cache flexible.


			==Shell Monitoring==

			The most obvious monitoring program is top

			also install some other popular tools:

			<pre>
			$ apt-get insall htop iotop ncdu
			</pre>

	=Related=		=Related=

Admin: /* Controlling Processes */

2016-03-14T03:23:26Z

Controlling Processes

@@ Line 12: / Line 12: @@
 * systemd journal
-==Controlling Processes==
+==Processes==
 In order to control a process, you must be able to find a process.
@@ Line 62: / Line 64: @@
 =Related=

Admin at 03:14, 14 March 2016

2016-03-14T03:14:27Z

← Older revision		Revision as of 03:14, 14 March 2016
Line 11:		Line 11:
	* systemd init system		* systemd init system
	* systemd journal		* systemd journal

			==Controlling Processes==

			In order to control a process, you must be able to find a process.

			Use the ps command to list currently running processes, and pass the aux argument to show everything:

			<pre>
			$ ps aux
			</pre>

			This shows a lot of information. Filter it out with grep:

			<pre>
			$ ps aux \| grep httpd
			</pre>

			This is also useful because it will display information about the cpu and memory usage.

			Now you can see its PID, and use that to kill the process:

			<pre>
			$ kill 15800
			</pre>

			THis will send a SIGTERM, or Signal 15, to the process. There are 18 different signals you can send, the SIGTERM is the nice polite request that the process stop.

			<pre>
			$ man 7 signal
			</pre>

			If you want to send a different signal, like 12, or 2,

			<pre>
			$ kill -12 15800
			$ kill -2 15800
			</pre>

			or if you are desparate, send a SIGKILL, Signal 9:

			<pre>
			$ kill -9 15800
			</pre>

			If you don't know the PID but you do know the process name, you can use the killall command:

			<pre>
			$ killall firefox
			</pre>

Admin: Created page with "=System Monitoring= What system monitoring entails: * inspect and manage processes * understand load average * available memory * checking stuff from a shell * disk space, st..."

2016-03-14T00:12:09Z

Created page with "=System Monitoring= What system monitoring entails: * inspect and manage processes * understand load average * available memory * checking stuff from a shell * disk space, st..."

New page

=System Monitoring=

What system monitoring entails:
* inspect and manage processes
* understand load average
* available memory
* checking stuff from a shell
* disk space, storage available
* logging
* log size, log rotate
* systemd init system
* systemd journal

=Related=

[[Linux/Networking]]

{{LinuxNetworkingFlag}}