使用rrdcached 減少ganglia 收集metric 的IO （ubuntu）

1. 修改 /etc/init.d/gmetad
   export RRDCACHED_ADDRESS=unix:/tmp/rrdcached.sock
2. 修改 /etc/default/rrdcached
   BASE_PATH=/var/lib/ganglia/rrds/
   PIDFILE=/tmp/rrdcached.pid
   SOCKFILE=/tmp/rrdcached.sock
   SOCKGROUP=nogroup
   DAEMON_GROUP=nogroup
   DAEMON_USER=nobody
   NETWORK_OPTIONS="-L"
   BASE_OPTIONS="-B -F -R"
3. chown -R nobody:nogroup /var/lib/rrdcached/journal
4. 修改 /var/www/html/ganglia/conf_default.php
   $conf['rrdcached_socket'] = 'unix:/tmp/rrdcached.sock';
5. service stop gmetad
   service stop rrdcached
   service start rrdcached
   service start gmetad
   service apache2 restart

ganglia 用multi source (cluster)

ganglia  有需要監控二個 source ， 一個hadoop 一個solr ..

ganglia 主機設定，改用unicast

1. gmetad.conf
    data_source "hadoop" 172.1.0.2:8649
    data_source "solr" 172.1.0.2:8655

2. 要設定二個 gmond.conf.1 gmond.conf.2 ， 開二個gmond 來收metric

     gmond.conf.1   (這個gmond 收也送，主機加入hadoop source)
         cluster {
         name = "hadoop"
         owner = "unspecified"
         latlong = "unspecified"
         url = "unspecified"
         }
         host {
           location = "unspecified"
         }
         udp_send_channel {
           host = 172.1.0.2
           port = 8649
           ttl = 1
         }
         udp_recv_channel {
          port = 8649
          bind = 172.1.0.2
         }
         tcp_accept_channel {
         port = 8649
         }

      gmond.conf.2 (這個gmond 就只收)

         cluster {
         name = "solr"
         owner = "unspecified"
         latlong = "unspecified"
         url = "unspecified"
         }
         host {
          location = "unspecified"
         }
         udp_recv_channel {
           port = 8655
          bind = 172.1.0.2
         }
         tcp_accept_channel {
          port = 8655
         }
3. 執行gmond
    /usr/sbin/gmond  --conf /etc/ganglia/gmond.conf.1
    /usr/sbin/gmond  --conf /etc/ganglia/gmond.conf.2

    或改daemon 的shell  , /etc/init.d/ganglia-monitor
         start-stop-daemon --start --quiet --name gmond1 \
                --exec $DAEMON -- --pid-file /var/run/$NAME.pid.1 --conf /etc/ganglia/gmond.conf.1
        start-stop-daemon --start --quiet --name gmond2 \
                --exec $DAEMON -- --pid-file /var/run/$NAME.pid.2 --conf /etc/ganglia/gmond.conf.2