如何通過upstart和monit支持多個nodejs服務？

Question

我創建了一個upstart腳本，以便守護node.js應用程序：

description "app_name"

start on startup
stop on shutdown

script
    export HOME="/home/ubuntu/nodeapp"

    exec sudo -u nodejs /usr/local/bin/node $HOME/app/server.js production 2>>/var/log/app_name.error.log >>/var/log/app_name.log
end script

我的monit腳本如下：

check host app_name with address 127.0.0.1
    start "/sbin/start app_name"
    stop "/sbin/stop app_name"
    if failed port 80 protocol HTTP
        request /ok
        with timeout 5 seconds
        then restart

它工作正常，但現在我想將nginx作為負載均衡器添加到上游，如下所示：

upstream cluster1 {
  least_conn;
  server 127.0.0.1:8000;
  server 127.0.0.1:8001;
}

server {
    listen 0.0.0.0:80;

    location / {
    proxy_pass http://cluster1;
    }
}

那么我應該如何更改upstart和monit腳本來支持它呢？

Answer 1

您應該創建三個monit檢查，一個用於nginx，一個用於每個nodejs實例：

check host nginx with address 127.0.0.1
    start "/sbin/start nginx"
    stop "/sbin/stop nginx"
    if failed port 80 protocol HTTP
        request /ok
        with timeout 5 seconds
        then restart

check host app_name_on_8000 with address 127.0.0.1
    start "/sbin/start app_name_on_8000"
    stop "/sbin/stop app_name_on_8000"
    if failed port 8000 protocol HTTP
        request /ok
        with timeout 5 seconds
        then restart

check host app_name_on_8001 with address 127.0.0.1
    start "/sbin/start app_name_on_8001"
    stop "/sbin/stop app_name_on_8001"
    if failed port 8000 protocol HTTP
        request /ok
        with timeout 5 seconds
        then restart

這將在失敗時重新啟動nodejs實例，如果失敗則nginx或兩個nodejs實例都關閉