large partitions greater than 2TB

[CentOS] LVM on large partitions greater than 2TB
http://lists.centos.org/pipermail/centos/2007-February/032574.html

nagios linux nrpe設定(3)使用nagios-plugins

參考
http://nagios.sourceforge.net/docs/nrpe/NRPE.pdf
http://www.debianhelp.co.uk/nagiospluins.htm

比較：
nagios server端：192.168.1.2 ，已在web server根目錄放 index.html 的 nagios server端
client 端：192.168.1.133，web server根目錄沒東西，check_http 正常會回應 403 Forbidden

兩者在 nrpe.cfg 都沒定義  check_http ，但 command-plugins.cfg 有command[check_http]

nagios linux nrpe設定(2)-基本安裝

*被監視端：
從剛裝好完全沒東西的 VM開始…

CentOS5.5 用 rpmforge 的來源做 yum 安裝，plugins 是放在
/usr/lib64/nagios/plugins/


yum install nrpe
會安裝
fping
nagios-plugins
perl-Crypt-DES
perl-Net-SNMP

nagios linux nrpe設定

server 裝好的 localhost

CentOS5.5 用 rpmforge 的來源做 yum 安裝，plugins 是放在
/usr/lib64/nagios/plugins/

...首先
/etc/nagios/nrpe.cfg 裡的
server_address=
allow_hosts=
後面跟的 IP 不能用逗點加別的 ip (例如：192.168.2.3,127.0.0.1)
目前先試只定義 server_address 1個 IP
allow_hosts 註解掉

iptables 加上   -p tcp -m tcp --dport 5666 -j ACCEPT

nagios linux nrpe設定(5) 另外加 plugins & command(2)

想新增一項目來看Linux client端的記憶體使用情形（Windows的預設有此項目）
預設沒有此command可處理…
記錄改了多少東東…

實作完…問題在佈署

Client 端(安裝 nagios-nrpe ，nagios-nrpe-plugins)
*在 /usr/lib64/nagios/plugins/  新增command用的shell script，
記得chmod 755（權限要跟其它plugin一樣）

實作時用的是下列討論區用的 script：
http://serverfault.com/questions/195815/nagios-memory-configuration
另有一版本可參考
http://www.linuxquestions.org/questions/linux-software-2/nagios-check-ram-usage-on-remote-server-747531/

vi /usr/lib64/nagios/plugins/check_memeory.sh

#!/bin/bash
#
# Script to check memory usage on Linux. Ignores memory used by disk cache. 
#
# Requires the bc command
#
print_help() {
    echo "Usage:"
    echo "[-w] Warning level as a percentage" 
    echo "[-c] Critical level as a percentage" 
    exit 0
}

while test -n "$1"; do
    case "$1" in
        --help|-h)
            print_help
            exit 0
            ;;
        -w)
            warn_level=$2
            shift
            ;;
        -c)
            critical_level=$2
            shift
            ;;
        *)
            echo "Unknown Argument: $1"
            print_help
            exit 3
            ;;
    esac
    shift
done

if [ "$warn_level" == "" ]; then
    echo "No Warning Level Specified"
    print_help
    exit 3;
fi

if [ "$critical_level" == "" ]; then
    echo "No Critical Level Specified"
    print_help
    exit 3;
fi


free=`free -m | grep "buffers/cache" | awk '{print $4}'`
used=` free -m | grep "buffers/cache" | awk '{print $3}'`

total=$(($free+$used))

result=$(echo "$used / $total * 100" |bc -l|cut -c -2)

if [ "$result" -lt "$warn_level" ]; then
    echo "Memory OK. $result% used."
    exit 0;
elif [ "$result" -ge "$warn_level" ] && [ "$result" -le "$critical_level" ]; then
    echo "Memory WARNING. $result% used."
    exit 1;
elif [ "$result" -gt "$critical_level" ]; then
    echo "Memory CRITICAL. $result% used."
    exit 2;
fi

chmod 755 /usr/lib64/nagios/plugins/check_memeory.sh
Client本機端試用：
sh  /usr/lib64/nagios/plugins/check_memory.sh
sh  /usr/lib64/nagios/plugins/check_memory.sh -w 80 -c 95


*在 /etc/nagios/nrpe.cfg 新增 command

##self defined## MEMORY Check
# check_mem   = MEMORY at defined warning and critical use %.
command[check_memory]=/usr/local/nagios/libexec/check_memory.sh -w $ARG1$ -c $ARG2$

service nrpe restart

Nagios Server端
*在 /etc/nagios/objects/commands.cfg 新定義 command

define command{
command_name check_memory
command_line $USER1$/check_memory.sh -w $ARG1$ -c $ARG2$
}

*在 對象設定檔.cfg 新增 service
測試對象：localhost.cfg
  vi /etc/nagios/objects/localhost.cfg

define service{
        use                   local-service;Name of service template to use
        host_name             localhost
        service_description   Memory Use
        check_command         check_memory!80!90
        }

service nagios restart