Nagios Monitor Linux host Memory script instance "operational maintenance"

Description

The work consists of two parts of the monitoring end (123) and the monitored end (iv)

One, nrpe.cfg add script

Add a command index to the NRPE.CFG

COMMAND[CHECK_USED_MEM]=/USR/LOCAL/NAGIOS/LIBEXEC/CHECK_USED_MEM.SH 80 90

Description: Actual memory usage exceeds 80% warnings; more than 90% critical warnings

Second, add specific script

Reference Script check_used_mem.sh


Warn=$1
Critical=$2
All= ' Free | Sed-n ' 2p ' | awk ' {print $} '
Used= ' Free | Sed-n ' 3p ' | awk ' {print $} '
Let "c= $used *100/$all"
if [[$c-lt $warn]]
Then
echo "used Mem/total < $warn% [used: $used, total: $total: $all]"
Exit 0
elif [[$c-lt $critical]]
Then
echo "used mem/total≥ $warn% [used: $used, total: $total: $all]"
Exit 1
Else
echo "used mem/total≥ $critical% [used: $used, total: $total: $all]"
Exit 2
Fi



Explain:

1.1, 2 respectively refers to the input of the first to second parameter, such as:

del.sh script content is

#/bin/bash
echo $

SH del.sh a #第一个参数是a
chmod a+x./del.sh a #第一个参数是a

2. Free to view the use of memory

[Root@xen_202_12/]# Free-m
Total used free shared buffers Cached
mem:3072 2459 612 0 207 1803
-/+ buffers/cache:447 2624
swap:1913 0 1913

Total Memory: 3072
Number of memory used has used: 2459
Free amount of Memory: 612
Shared is currently obsolete no, always 0
Buffers:buffer Cache Memory Number: 13220
Cached:page Cache Memory Number: 2720160

Relationship: total = used + Free

Line 3rd:
The meaning of-/+ Buffers/cache:
-buffers/cache Memory: 447 (equal to used-buffers-cached on line 1th)
+buffers/cache Memory: 2624 (equal to line 1th Free + buffers + cached)
Note: The amount of memory here is a little bit different in size (not knowing what the reason is), after using the above formula.

Visible-buffers/cache reflects the memory that is actually eaten by the program, and +buffers/cache reflects the total amount of memory that can be misappropriated.

3. Sed-n ' 2p ' refers to finding the second line

4. awk ' {print $} ' refers to the second column, which is separated by a space by default. You can use-f to specify a separator

$echo 1b234b56b7 | Awk-f ' B ' {print $} '
234

5. Practical [[]],< used to compare strings;-lt used to compare numbers

Third, restart Nrpe

/usr/local/nagios/bin/nrpe-c/usr/local/nagios/etc/nrpe.cfg-d

Iv. Adding monitoring items to the monitoring side


Define Service {
Use Generic-service
HOST_NAME 100.61.73.2,100,61,73.3
Service_description Memory
Check_command Check_nrpe!check_used_mem
Notifications_enabled 1
}


using Python scripts to monitor Linux hosts in Nagios

192.168.5.110 at the monitored end
1. Put the getload.py in the/usr/local/nagios/libexec first.
[Root@nhserver1 ~]# vim/usr/local/nagios/libexec/getload.py
#! /usr/bin/env python
Import Os,sys
(D1,D2,D3) = Os.getloadavg ()
If D1 >= 5.0:
Print "Getloadavg critical:load average is%.2f"% (D1)
Sys.exit (2)
elif D1 >= 2.0:
Print "Getloadavg warning:load average is%.2f"% (D1)
Else
Print "Getloadavg ok:load average is%.2f"% (D1)

[Root@nhserver1 libexec]# chmod a+x getload.py
[Root@nhserver1 libexec]# chown Nagios:nagios getload.py


2. Add custom commands within Nrpe
[Root@nhserver1 libexec]# Vim/usr/local/nagios/etc/nrpe.cfg
command[nh_check_getload]=/usr/local/nagios/libexec/getload.py

------------------------------------------------------------------------------------------

Test 192.168.5.10 on the Nagios service side

[Root@nhserver2 libexec]#/usr/local/nagios/libexec/check_nrpe-h 192.168.5.110-c nh_check_getload
Getloadavg ok:load Average is 0.06

Add a custom script to the Nagios of the server-side test 192.168.5.10
[Root@nhserver2 ~]# Cd/usr/local/nagios/etc/objects
[Root@nhserver2 objects]# Vim Hosts_192.168.5.110.cfg
Define Host{
Use Linux-server
HOST_NAME 192.168.5.110
Alias 192.168.5.110
Address 192.168.5.110
}

Define Hostgroup{
Hostgroup_name Nh_linuxs
Alias Nh_linuxs
Members 192.168.5.110
}

Define Service{
Use Local-service
HOST_NAME 192.168.5.110
Service_description check-host-alive
Check_command check-host-alive
Max_check_attempts 5
Normal_check_interval 3
Retry_check_interval 2
Check_period 24x7
Notification_interval 10
Notification_period 24x7
}

Define Service{
Use Local-service
HOST_NAME 192.168.5.110
Service_description SSH
Check_command Check_ssh
Max_check_attempts 5
Normal_check_interval 3
Retry_check_interval 2
Check_period 24x7
Notification_interval 10
Notification_period 24x7
}

Define Service{
Use Local-service
HOST_NAME 192.168.5.110
Service_description check_nrpe_check_users
Check_command check_nrpe!nh_check_users
Max_check_attempts 5
Normal_check_interval 3
Retry_check_interval 2
Check_period 24x7
Notification_interval 10
Notification_period 24x7
}
Define Service{
Use Local-service
HOST_NAME 192.168.5.110
Service_description Check_nrpe_check_getload
Check_command Check_nrpe!nh_check_getload
Max_check_attempts 5
Normal_check_interval 3
Retry_check_interval 2
Check_period 24x7
Notification_interval 10
Notification_period 24x7
}

[Root@nhserver2 objects]# Service Nagios Reload

The state that is visible in Nagios services.
192.168.5.110
Check_nrpe_check_getload
OK 04-17-2014 16:21:53 0d 0h 4m 22s 1/5 getloadavg ok:load average is 0.00