I'm newbie using GCP and his Compute Engine Service. I've deploy a Linux Ubuntu Image an it's running like a charm, but I have a issue running Node JS backend.
Let me explain it better:
I'm connecting using Web Browser SSH terminal or GCloud Shell ssh, and it way works running node app.js my backend starts working. But after a time, the sessions stop and my backend service stop working as well. At this time every time when I need to work have to re-activate the service each time.
How could I do for this service works in background and not depends that my ssh terminal are opened?
Thanks a lot in advance.
What actually happen is you are starting your nodejs application using an client which is parent process. So if after sometime the connection is lost of some xyz seconds the parent process dies killing your node application. Now what you can do is use screen. On ubuntu you would do something like this.
sudo apt-get install screen
after successful install run the screen command. Now you will be thrown a brand new terminal. Here you can run your nodejs code which will never die. Since screen runs your application in background. More information here
A good solution could be to use a startup script. To insert a startup script into your already created instance you need to go to this link [1]. When you have your startup script inserted in the metadata field you just need to restart your Instance and then should work perfectly without depending of the ssh session.
[1] https://cloud.google.com/compute/docs/startupscript#startupscriptrunninginstances
I've created this npm package, to make your node app run as a service on your linux machine. Please try it out.
It creates a systemctl service on your machine and runs it as a background service.
Related
I have a Google VM, and i can start a web server. The command i issue is: python server.py.
My plan is to have the application running.
Since i will eventually close my pc (and thus the terminal), will the application continue running normally?
Or, do i have to start the server and then use disown, to make the app run in the background?
NOTE: If the second option is the case, does this mean that when i re-log in, and i want to shut down the server, the only way to do it is with pkill?
How to keep a node application running in windows even when user logs off?
Also how to keep running a node http-server even after user log-off?
You have 2 great options. One is as mentioned in comments above Forever.
The other is PM2 which is easy to install and offers an incredible amount of options. I use this in all projects, but I cannot attest to the Windows version as I am on Linux & Ubuntu servers and work on a Mac. You can daemonize your node process, follow logs, cluster it and make sure the process reboots even with a server shutdown (it is a service).
windows task scheduler: execute node.exe: start in project folder: and argument (app.js)
I have a website already developed with node.js and sails.js on "Compute Engine" but to start it, necessarily I have to write "node app.js" in the SSH console of browser. But there is a problem (since I am new to Linux and Google Cloud :)), if I want my Node app it keep online, the SSH window must be open, if I close, the Node application will terminate, like Ctrl+c. So it makes no sense to have my computer turned on, just to have the active window. So, how to keep my NodeJS app online without being in the presence of SSH console?. I know the question is illogic to some, but I would appreciate if you help me. Thanks
First of all it is not related to Compute Engine nor Node.js.
You mention that the application will terminate if you press ctrl+c and that's correct because you are running your application in the foreground instead of background. To run your application in the background you can either launch your app like this:
node app.js &
Or you can launch with node app.js and then press ctrl+z.
But just sending the application to the background wouldn't help. As soon as you disconnect from your ssh session, all programs started (background or foreground) will receive a HUP signal, in node.js you can handle that signal but the default behaviour is to close:
On non-Windows platforms, the default behaviour of SIGHUP is to terminate node
One thing that you can do to ignore the SIGHUP signal is running your app as follows:
nohup node app.js &
If you do this, your application will continue to run even when you close your ssh session. Another way to achieve this is by using the screen.
This will help you on very early stage and for development but I don't recommend using neither of these things for production. Eg: if your application crash it should be restarted. The recommended way is to use a service manager that comes with the OS: upstart, systemd, init, to name a few.
You can install forever module (https://www.npmjs.com/package/forever) to your Google compute engine using SSH window.
npm install forever -g
Then, in your node server directory, execute your server using forever.
forever start [YOUR_SERVER_FILE.js]
Now, if you close the SSH window, your node server is still on !!
Good luck!
The best solution would be using a module called forever:
https://www.npmjs.com/package/forever
You can use it this way:
forever start your_script.js
I have deployed a Bitnami AMI of NodeJS on an AWS micro instance. After starting my node app, everything works fine.
After some time without any activity, the app which is attached to port :3000, seems to shut down. When this happens on refreshing the page my browser gives the message:
Network Error (tcp_error)
A communication error occurred: "Connection refused"
The Web Server may be down, too busy, or experiencing other problems preventing it from responding to requests. You may wish to try again at a later time.
The AWS console shows the instance is still running and the Bitnami build still responds with the standard message on port 80.
Forever (https://github.com/nodejitsu/forever) is also a useful tool for this kind of thing, and it gives you a little more control than nohup or screen.
As we discussed in comments, the problem was binding the node process to SSH session.
You can use nohup or screen to launch the node process in an instance not bound to session.
I suggest using screen because the function of returning to launched instance is essential for maintenance/updating.
Related: How to run process as background and never die
Related: Command-Line Interface tool to run node as a service
Besides configuring an EC2-instance you can also use the PaaS-solution of AWS, namely Elastic Beanstalk. They have also support for Node.js and it's super easy to deploy your apps using this service.
I absolutely 100% new to VPS and linux as of yesterday, and I'm running into an issue. Here's the process:
I SSH into my VPS box in OSX terminal. The VPS is running CentOS 6 for what it's worth.
I navigate to the correct folder and I run node app.js to launch my app in NodeJS/ExpressJS.
App launches and is readily accessible via the web at my VPS' ip address + the allocated port number.
If I put my laptop to sleep, the app crashes and is no longer accessible via web.
Again, being new to Linux I'm not sure how to solve this problem. It makes sense, as the terminal that was running/taking logs of the node app is no longer responding, but what I'd like is:
a) To be able to start up the app remotely then have it just...run...forever, until I manually stop it
b) To be able to SSH back into my server intermittently to check the logs, either via my mobile phone or my laptop.
Are either of these two things possible? Clearly my protocol of launching the app via terminal (as I'd normally do if running it locally) isn't the correct way to do it but I'm having trouble finding resources telling me what to do!
EDIT: I'm actually using Node Supervisor to run the app which helps keep it up and running when things crash, not sure if that affects the situation.
Most probably your app is printing to standard out (the console), and that stream is closed/broken, when you put your laptop to sleep.
There are at least two options:
Use screen: Just type screen before starting your app. Then start your app. Then Ctrl-A-D to detach from the screen. You can then safely log out from the VPS and put your laptop to sleep. To go back to the output of your app, log back in and type screen -r
Run the app in the background: node app.js &.