在开始配置前，请确保您的云服务器满足以下条件：

• 操作系统：CentOS 7/8或Ubuntu 18.04/20.04
• root权限或sudo权限
• 至少2GB内存（建议4GB以上）
• 开放80/443端口（Web访问）

1. 安装依赖包

# CentOS
yum install -y httpd php gcc glibc glibc-common gd gd-devel make net-snmp

# Ubuntu
apt-get install -y apache2 php libapache2-mod-php build-essential libgd-dev

2. 创建Nagios用户

useradd nagios
usermod -a -G nagios apache  # Ubuntu使用www-data

3. 下载并编译安装

wget https://assets.nagios.com/downloads/nagioscore/releases/nagios-4.4.6.tar.gz
tar xzf nagios-*.tar.gz
cd nagios-4.4.6
./configure --with-httpd-conf=/etc/apache2/sites-enabled
make all
make install
make install-init
make install-config
make install-commandmode

1. 设置Web认证

htpasswd -c /usr/local/nagios/etc/htpasswd.users nagiosadmin

2. 配置Apache虚拟主机

# CentOS
cp sample-config/httpd.conf /etc/httpd/conf.d/nagios.conf

# Ubuntu
cp sample-config/httpd.conf /etc/apache2/sites-available/nagios.conf
a2ensite nagios

3. 重启服务

systemctl restart apache2
systemctl start nagios

1. 主机配置文件

编辑/usr/local/nagios/etc/objects/hosts.cfg：

define host {
    host_name               web-server
    alias                   Web Server
    address                 192.168.1.100
    check_command           check-host-alive
    max_check_attempts      5
    check_period            24x7
    notification_interval   30
    notification_period     24x7
}

2. 服务监控示例

编辑/usr/local/nagios/etc/objects/services.cfg：

define service {
    host_name               web-server
    service_description     HTTP
    check_command           check_http
    max_check_attempts      3
    normal_check_interval   5
    retry_check_interval    1
}

1. NRPE插件远程监控

# 在被监控节点安装NRPE
yum install -y nrpe nagios-plugins-all

# 编辑/etc/nagios/nrpe.cfg
allowed_hosts=监控服务器IP

2. 邮件报警配置

define contact {
    contact_name                    nagiosadmin
    alias                           Nagios Admin
    service_notification_period     24x7
    host_notification_period        24x7
    service_notification_options    w,u,c,r
    host_notification_options       d,u,r
    service_notification_commands   notify-service-by-email
    host_notification_commands      notify-host-by-email
    email                           admin@yourdomain.com
}