nagios监控系统安装(1)
nagios http://www.nagios.org
完整的nagios中包含几个组成部分：
1、nagios软件本身，必须安装；
2、plugins，必须安装，是nagios用来监测远程主机运行状况的一系列小程序，安装后默认在/usr/local/nagios/libexec下；
3、npre，非必需，如果希望对机器的磁盘、进程、负载等状况进行监测并报警，那么就需要在该机器上安装；
4、ndoutils，非必需，将nagios的数据保存到mysql数据库中。
一篇不错的文章在：http://www.linuxtone.org/viewthread.php?tid=514，我学习了他的方法。
Nagios官网文档中有在Ubuntu下的安装指南，Debian基本相同：http://nagios.sourceforge.net/docs/3_0/quickstart-ubuntu.html。
我准备采用的应用程序路径都是默认的，如：
/usr/local/nginx
/usr/local/nagios
1、安装前的一些准备
安装部分软件：apt-get install build-essential libgd2-xpm-dev libssl-dev openssl libkrb5-dev
安装好web服务器，我用的是nginx，可以采用apache会更方便。
2、准备用户、用户组
/usr/sbin/useradd -m nagios
/usr/sbin/groupadd nagcmd
/usr/sbin/usermod -a -G nagcmd nagios
/usr/sbin/usermod -a -G nagcmd www-data
3、安装nagios
到http://www.nagios.org/download/download.php下载最新的Nagios和Nagios plugins。
解压后，进入nagios目录：
./configure –with-command-group=nagcmd
make all
make install
make install-init
make install-config
make install-commandmode
进入nagios plugins目录：
./configure –with-nagios-user=nagios –with-nagios-group=nagios
make
make install
4、配置nginx支持perl fcgi
nginx要支持perl fcgi，可以采用脚本perl-fcgi.pl如下：
#!/usr/bin/perl
use FCGI;
#perl -MCPAN -e ‘install FCGI’
use Socket;
#this keeps the program alive or something after exec’ing perl scripts
END() { } BEGIN() { }
*CORE::GLOBAL::exit = sub { die “fakeexit\nrc=".shift()."\n”; }; eval q{exit}; if ($@) { exit unless $@ =~ /^fakeexit/; } ;
&main;
sub main {
#$socket = FCGI::OpenSocket( “:3461”, 10 ); #use IP sockets
$socket = FCGI::OpenSocket( “/var/run/nagios.sock”, 10 ); #use UNIX sockets - user running this script must have w access to the ’nginx’ folder!!
$request = FCGI::Request( *STDIN, *STDOUT, *STDERR, %ENV, $socket );
if ($request) {request_loop()};
FCGI::CloseSocket( $socket );
}
sub request_loop {
while( $request->Accept() >= 0 ) {
#processing any STDIN input from WebServer (for CGI-GET actions)
$env = $request->GetEnvironment();
$stdin_passthrough =’';
$req_len = 0 + $ENV{CONTENT_LENGTH};
if ($ENV{REQUEST_METHOD} eq ‘GET’){
$stdin_passthrough .= $ENV{‘QUERY_STRING’};
}
#running the cgi app
if ( (-x $ENV{SCRIPT_FILENAME}) && #can I execute this?
(-s $ENV{SCRIPT_FILENAME}) && #Is this file empty?
(-r $ENV{SCRIPT_FILENAME}) #can I read this file?
){
#http://perldoc.perl.org/perlipc.html#Safe-Pipe-Opens
open $cgi_app, ‘-|’, $ENV{SCRIPT_FILENAME}, $stdin_passthrough or print(“Content-type: text/plain\r\n\r\n”); print “Error: CGI app returned no output - Executing $ENV{SCRIPT_FILENAME} failed !\n”;
if ($cgi_app) {print <$cgi_app>; close $cgi_app;}
}
else {
print(“Content-type: text/plain\r\n\r\n”);
print “Error: No such CGI app - $req_len - $ENV{CONTENT_LENGTH} - $ENV{REQUEST_METHOD} - $ENV{SCRIPT_FILENAME} may not exist or is not executable by this process.\n”;
}
}
}
该脚本由start_nginx_cgi.sh调用启动，start_nginx_cgi.sh脚本如下：
#!/bin/bash
start_nginx_cgi.sh: start nginx cgi mode#
ljzhou, 2007.08.20#
PERL="/usr/bin/perl"
NGINX_CGI_FILE="/usr/local/nagios/bin/perl-cgi.pl"
#bg_num=jobs -l |grep "NGINX_CGI_FILE"
#PID=ps aux|grep "perl-cgi"|cut -c10-14|xargs kill -9
PID=ps aux|grep 'perl-cgi'|cut -c10-14|sed -n "1P"
echo $PID
sockfiles="/var/run/nagios.sock"
kill -9 $PID
$PERL $NGINX_CGI_FILE &
sleep 3
chown www-data.www-data $sockfiles
EOF: start_nginx_cgi.sh#
之后运行/usr/local/nagios/bin/start_nginx_cgi.sh，并将它加到/etc/rc.local中。
nginx中加入对nagios的配置——我是直接做了个从/usr/local/nagios/sbin到web根目录下nagios的链接，并在相关vhost文件中增加：
location ~ .cgi$ {
root /usr/local/nagios/sbin;
rewrite ^/nagios/cgi-bin/(.*).cgi /$1.cgi break;
fastcgi_index index.cgi;
auth_basic “Restricted”;
auth_basic_user_file nagios.pw;
fastcgi_pass unix:/var/run/nagios.sock;
fastcgi_param SCRIPT_FILENAME /usr/local/nagios/sbin$fastcgi_script_name;
fastcgi_param QUERY_STRING $query_string;
fastcgi_param REMOTE_ADDR $remote_addr;
fastcgi_param REMOTE_PORT $remote_port;
fastcgi_param REQUEST_METHOD $request_method;
fastcgi_param REQUEST_URI $request_uri;
#fastcgi_param SCRIPT_NAME $fastcgi_script_name;
fastcgi_param SERVER_ADDR $server_addr;
fastcgi_param SERVER_NAME $server_name;
fastcgi_param SERVER_PORT $server_port;
fastcgi_param SERVER_PROTOCOL $server_protocol;
fastcgi_param SERVER_SOFTWARE nginx;
fastcgi_param CONTENT_LENGTH $content_length;
fastcgi_param CONTENT_TYPE $content_type;
fastcgi_param GATEWAY_INTERFACE CGI/1.1;
fastcgi_param HTTP_ACCEPT_ENCODING gzip,deflate;
fastcgi_param HTTP_ACCEPT_LANGUAGE zh-cn;
}
之后重启nginx。
dbanotes提到过另一种使用perl fastcgi的方法，他的文章在：
http://www.dbanotes.net/techmemo/nginx_awstats_fastcgi_for_perl.html
其中提到的脚本参见：http://www.nginx.eu/nginx-fcgi.html
有时间的同学可以试试。
5、调整nagios配置文件
需要调整的文件包括：
/usr/local/nagios/etc/nagios.cfg
/usr/local/nagios/etc/cgi.cfg
/usr/local/nagios/etc/server/test.cfg
a./usr/local/nagios/etc/nagios.cfg
这是nagios的主配置文件，加入一句：
cfg_dir=/usr/local/nagios/etc/servers
b./usr/local/nagios/etc/cgi.cfg
use_authentication=0 #其实不推荐这样做，后续会做调整
c./usr/local/nagios/etc/server/hostgroup.cfg
在这里可以对服务器进行分组，这里的示例只有一组：
define hostgroup{
hostgroup_name update
alias update server
members test
}
d./usr/local/nagios/etc/server/test.cfg
这个test.cfg实际上是一台测试的受监控服务器，可以简单配置监控存活、HTTP、FTP，文件如下：
define host {
host_name test
address 61.123.120.10
check_command check-host-alive
max_check_attempts 4
notification_interval 300
notification_period 24x7
notification_options d,u,r
contact_groups admins
}
define service {
host_name test
check_period 24x7
max_check_attempts 4
normal_check_interval 1
retry_check_interval 1
contact_groups admins
notification_interval 600
notification_period 24x7
notification_options w,u,c,r
check_command check_ping!100.0,20%!500.0,60%
}
define service{
host_name test
service_description HTTP
check_period 24x7
max_check_attempts 4
normal_check_interval 1
notification_interval 600
notification_period 24x7
notification_options w,u,c,r
contact_groups admins
check_command check_http
notifications_enabled 1
}
define service{
host_name test
service_description FTP
check_period 24x7
max_check_attempts 4
normal_check_interval 1
notification_interval 600
notification_period 24x7
notification_options w,u,c,r
contact_groups admins
check_command check_ftp
}