PM2 allows to run NodeJS apps on multiple instances, i.e., different cores, allowing load balancing using the same port.
PORT=3000 pm2 start -i NUMBER_OF_CORES(e.g 2) app.js
But I could also do load balancing in Nginx with different ports
upstream app_servers {
server 127.0.0.1:3000;
server 127.0.0.1:3001;
server 127.0.0.1:3002;
server 127.0.0.1:3002;
}
server {
listen 80;
server_name your-domain.com www.your-domain.com;
location / {
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header Host $http_host;
proxy_pass http://app_servers;
}
}
and then
pm2 start app.js -f --3000
pm2 start app.js -f --3001
pm2 start app.js -f --3002
pm2 start app.js -f --3003
Which is the best idea (I always assume the localhost does all the service)?
- simply load balancing the same port on different instances (cores)
- simply load balancing on different ports and let OS manage instances, or
- load balancing by having different instances, each with a different port, thus using both Nginx and PM2 load balancers?
