Nagios之事件处理

角色

Host_ip

备注

Client

192.168.x.x

Nagios监控端作为Client，目的是为了远程执行脚本

Server

192.168.x.y

存启动服务脚本，如：mysql脚本

检查

SERVER端权限检查

[root@centos-server nagios]# ls -la /home/nagios|grep .ssh

drwx------- 2 nagios nagios 4096 Aug  3 09:04 .ssh

[root@centos-server nagios]# ls -la /home/nagios/.ssh/

total 12

drw------- 2 nagios nagios 4096 Aug  3 09:04 .

drwx------ 4 nagios nagios 4096 Aug  3 09:03 ..

-rw------- 1 nagios nagios  411 Aug  3 09:04 authorized_keys

请确保红色标识的内容(保证.ssh目录的权限为700, authorized_keys的权限为600)

nagios用户持有者

CLIENT端登录测试

[nagios@nagios ~]$ ssh nagios@192.168.x.y

Last login: Wed Aug  3 09:15:59 2011 from 192.168.x.x

[nagios@centos-server ~]$

看到没？从192.168.x.x登录到192.168.x.y无需密码了。

如果没有这样的效果，大家看下是不是前面的权限问题。我曾今也是因为权限折腾了我同事半天。哈哈。

Mysql控制(启动/停止等)脚本

#!/bin/sh

mysql_port=3306

mysql_username="admin"

mysql_password=" controlmysql "

mysql_scripts_path="/data0/mysql/3306"

mysqld_path="/usr/local/webserver/mysql"

start_mysql()

{

printf "Starting MySQL...\n"

/bin/sh ${mysqld_path}/bin/mysqld_safe --defaults-file=/data0/mysql/${mysql_port}/my.cnf 2>&1 > /dev/null &

}

stop_mysql()

{

printf "Stoping MySQL...\n"

${mysqld_path}/bin/mysqladmin -u ${mysql_username} -p${mysql_password} -S /tmp/mysql.sock shutdown

}

restart_mysql()

{

printf "Restarting MySQL...\n"

stop_mysql

sleep 5

start_mysql

}

kill_mysql()

{

kill -9 $(ps -ef | grep 'bin/mysqld_safe' | grep -v 'grep'| awk '{printf $2}')

kill -9 $(ps -ef | grep 'libexec/mysqld' | grep -v 'grep' |awk '{printf $2}')

}

if [ "$1" = "start" ]; then

start_mysql

elif [ "$1" = "stop" ]; then

stop_mysql

elif [ "$1" = "restart" ]; then

restart_mysql

elif [ "$1" = "kill" ]; then

kill_mysql

else

printf "Usage: ${mysql_scripts_path}/mysql {start|stop|restart|kill}\n"

fi

检查

SERVER端脚本测试检查

[root@centos-server ~]# netstat -an|grep 3306

[root@centos-server ~]#

说明mysql没有起来

[root@centos-server ~]# /data0/mysql/3306/mysql start

Starting MySQL...

[root@centos-server ~]# netstat -an|grep 3306

tcp        0      0 :::3306                     :::*                        LISTEN

[root@centos-server ~]#

脚本OK，正常

Client端测试(以nagios用户登录)

[nagios@nagios ~]$ ssh nagios@192.168.x.y "sudo /data0/mysql/3306/mysql start"

sudo: sorry, you must have a tty to run sudo

解决：

Server端修改visudo，将下面一行注释

Defaults    requiretty

再试

[nagios@nagios ~]$ ssh nagios@192.168.x.y "sudo /data0/mysql/3306/mysql start"

Starting MySQL...

正常启动

检查SERVER端 端口3306是否存在

恭喜，基本功已经做完。我们可以去玩监控端nagios配置了

mfs_hosts.cfg

define host{

use                     mfs-server

host_name               mfs-192.168.x.y

alias                   mfs-192.168.x.y

address                 192.168.x.y

}

mfs_hostgroups.cfg

define hostgroup{

hostgroup_name  mfs-servers

alias           Mfs Linux Servers

members        mfs-192.168.x.y

}

mfs_services.cfg

define service {

name                    mfs-services

service_description     checkport

check_command           check_tcp!3306

check_period            24x7

max_check_attempts      2

normal_check_interval   3

retry_check_interval    1

notification_interval   5

notification_period     24x7

notification_options    w,u,c,r

register                   0

}

define service{

use                             mfs-services

host_name                       mfs-192.168.x.y

        event_handler_enabled   1

        event_handler          restart_mysql

}

define service{

use                             mfs-service

host_name                       mfs-192.168.x.y

service_description             PING

check_command                   check_ping!100.0,20%!500.0,60%

}

commands.cfg

define command{

command_name    restart_mysql

command_line    /usr/local/nagios/libexec/restart_mysql $SERVICESTATE$ $SERVICESTATETYPE$ $SERVICEATTEMPT$  $HOSTADDR

ESS$

}

restart_mysql

HostAddress=$4

debug=1

if [ $debug -eq 1 ];then

echo "MysqlServer:${HostAddress}" >>/tmp/ReMysql.log

fi

case "$1" in

OK)

;;

WARNING)

;;

UNKNOWN)

;;

CRITICAL)

case "$2" in

SOFT)

case "$3" in

1)

if [ $debug -eq 1 ];then

echo  "Restarting Mysql service (1rd soft critical state)..." >>/tmp/ReMysql.log

fi

/usr/bin/ssh nagios@${HostAddress} "sudo /data0/mysql/3306/mysql start"

;;

esac

;;

HARD)

if [ $debug -eq 1 ];then

echo  "Restarting Mysql service..." >>/tmp/ReMysql.log

fi

/usr/bin/ssh nagios@${HostAddress} "sudo /data0/mysql/3306/mysql start"

;;

esac

;;

esac

exit 0

注明：测试最好将debug设置为1

申明：本脚本暂时的作用是远程重启mysql，后续还要添加写入数据库的脚本。

检查

Nagios配置文件检查

/usr/local/nagios/bin/nagios –v /usr/local/nagios/etc/nagios.cfg

无错误,重启nagios

Service nagios restart

被监控端开启mysql等相关服务，保证监控一切正常!如图：

尝试正常关闭mysql服务

实现目标：当出现第一次软状态的critical情况下，去尝试重启mysql.

以下4条信息足以证明我们想达到的效果已经实现!

(1)检查监控端nagios图

(2)检查监控端脚本日志

[root@nagios tmp]# tail -f ReMysql.log

MysqlServer:192.168.x.y

Restarting Mysql service (1rd soft critical state)...

(3)被监控端检查端口是否存在

[root@centos-server ~]# netstat -an|grep 3306

tcp        0      0 :::3306                     :::*                        LISTEN

(4)再检查监控端nagios图

注明：到这里我们已经实现了第一个想法，就是远程重启服务。下面，我们要实现将事件记录到mysql中。

角色

Host_ip

备注

Client

192.168.x.x

Nagios监控端作为Client，执行将报错信息写入数据库脚本

DB Server

192.168.x.z

存储报错信息的DB

Perl远程操作mysql脚本

#!/bin/perl

#Last Modifed by Hahazhu 2011/08/03

use DBI;

##########INIT DEFINED###########

my $remote_mysql="192.168.x.z";

my $remote_db="nagios";

my $remote_mysql_user="nagioslog";

my $remote_mysql_pwd="12345678";

my $debug=1;

##########Recevice Values#########

my $host_ip=$ARGV[0];

my $service_desc=$ARGV[1];

my $plugin_out=$ARGV[2];

my $dbh = DBI->connect("DBI:mysql:database=$remote_db;host=$remote_mysql", "$remote_mysql_user", "$remote_mysql_pwd", {'RaiseError'

=> 1});

my $rows = $dbh->do("INSERT INTO log (host_ip, services_desc, plugin_out) VALUES ('$host_ip', '$service_desc', '$plugin_out')");

if ($debug){

print "$rows row(s) affected \n";

}

if($debug){

my $sth = $dbh->prepare("SELECT host_ip, services_desc , plugin_out FROM log");

$sth->execute();

while (@data=$sth->fetchrow_array()){

print "$data[0] $data[1] $data[2]\n";

}

}

$dbh->disconnect();

申明：测试前请将$debug设置为1.

检查

Nagios端以nagios用户执行插入数据脚本

[nagios@nagios libexec]$ perl insert_log_to_mysql.pl 1.1.1.1 check_3306 "connection refused"

1 row(s) affected

1.1.1.1    check_3306 connection refused

DB Server端检查

mysql> select * from log;

+---------+---------------+--------------------+

| host_ip | services_desc | plugin_out         |

+---------+---------------+--------------------+

| 1.1.1.1 | check_3306    | connection refused |

+---------+---------------+--------------------+

1 row in set (0.00 sec)

OK，脚本测试无问题。后面的工作就是将其加入到nagios配置里了。

Commands.cfg

define command{

command_name    restart_mysql

command_line    /usr/local/nagios/libexec/restart_mysql $SERVICESTATE$ $SERVICESTATETYPE$ $SERVICEATTEMPT$  $HOSTADDRESS$ $SERVICEDESC$ "$SERVICEOUTPUT$"

}

启动mysql脚本要调整restart_mysql

#/bin/sh

HostAddress=$4

Services_desc=$5

Plugin_out=$6

debug=1

if [ $debug -eq 1 ];then

echo "MysqlServer:${HostAddress}" >>/tmp/ReMysql.log

fi

case "$1" in

OK)

;;

WARNING)

;;

UNKNOWN)

;;

CRITICAL)

case "$2" in

SOFT)

case "$3" in

1)

if [ $debug -eq 1 ];then

echo  "Restarting Mysql service (1rd soft critical state)..." >>/tmp/ReMysql.log

fi

/usr/bin/perl /usr/local/nagios/libexec/insert_log_to_mysql.pl ${HostAddress} ${Services_desc} ${Plugin_out}

/usr/bin/ssh nagios@${HostAddress} "sudo /data0/mysql/3306/mysql start"

;;

esac

;;

HARD)

if [ $debug -eq 1 ];then

echo  "Restarting Mysql service..." >>/tmp/ReMysql.log

fi

/usr/bin/perl /usr/local/nagios/libexec/insert_log_to_mysql.pl ${HostAddress} ${Services_desc} “${Plugin_out}”

/usr/bin/ssh nagios@${HostAddress} "sudo /data0/mysql/3306/mysql start"

;;

esac

;;

esac

exit 0

申明：调试前最好把debug设置为1

检查

到了本文最后一部分了，有点激动…

看看，我们验证能不能达到我们下面的目标.

实现目标：

重启mysql服务，必把相关日志记录到另一台mysql DB中。

试验：stop mysql服务

Nagios端检查图：

Nagios端日志:

[root@nagios ~]# tail -f /tmp/ReMysql.log

MysqlServer:192.168.x.y

Restarting Mysql service (1rd soft critical state)...

此时检查mysql服务端

[root@centos-server ~]# netstat -an|grep 3306

tcp        0      0 :::3306                     :::*                        LISTEN

再检查记录日志情况：

mysql> select * from nagios.log;

+--------------+---------------+--------------------+

| host_ip      | services_desc | plugin_out         |

+--------------+---------------+--------------------+

| 192.168.x.y | checkport     | Connection refused |

+--------------+---------------+--------------------+

1 row in set (0.00 sec)

OK，目标已经实现。不仅实现了远程开机。而且将错误记录下来了。