Hadoop's load monitoring software ganglia

ganglia：
======================
    Load monitoring software


    gmond         // Monitor resource occupancy on all hosts 
    gmetad         // Collect all hosts gmond information on a node through ports 
    gweb         // Collect gmetad information and show it to users


Install ganglia:
=======================
    0. Uninstall mysql source to prevent upgrade
        sudo yum remove mysql-community-release.noarch

    1. First install the yum source of ganglia, two ways s101- s105
         1 ) In case of network
            sudo yum -y install epel-release

        2 ) Without network
            sudo yum -y localinstall epel-release-7-9.noarch.rpm
    
    2. Install gmond: s101- s105
         1 ) When there is a network
            sudo yum install - y gmond
         2 ) without network
            cd gmond
            sudo yum localinstall -y *.rpm

    3. Install gmetad: s101
         1 ) In case of network
            sudo yum install -y gmetad
         2 ) no network
            cd gmetad
            sudo yum localinstall -y *.rpm

    4. Install gweb: s101
         1 ) Install httpd and php
            sudo yum install -y httpd php
         2 ) no network
            cd httpd
            sudo yum localinstall -y * .rpm
         3 ) Download and install gweb
            tar -xzvf ganglia-web-3.7.2 .tar.gz
            cd ganglia -web-3.7.2 directory
            nano Makefile
            Modify GDESTDIR = /var/www/ html
            Modify APACHE_USER = apache
         4 ) compile and install
            sudo make install

    5. Start the service:
        sudo service httpd start    //s101
        sudo service gmetad start    //s101
        sudo service gmond start    //s101-s105

    6. Check the status
        systemctl status httpd
        systemctl status gmetad
        systemctl status gmond

    7. Turn off SELinux, otherwise there will be permission problems     // s101
        sudo setenforce 0

    8. Set the boot to start
        systemctl enable httpd
        systemctl enable gmetad
        systemctl enable gmond

    9. Enter http: // s101:80 in the browser to access