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?
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When you are writing a node application on your computer, you can run it from your computer by typing in node . However, how does that happen when the application is being deployed.
When you are writing a node application on your computer, you can run it from your computer by typing in node . However, how does that happen when the application is being deployed.
Basically the same way: there's not much of a difference between your computer and a computer in a data center. Either way, you start the process and it runs. It binds to a port that must be open, and then some firewall must be configured to allow incoming connections from the Internet to reach that port.
How you start the process in your "deployed" application varies greatly and is up to your needs and taste. You can:
1) Provision a server somewhere, install node on there, put your code there, and then run your application. You run it in the same way as your local computer. Log in to the computer and execute node. Or you can set it up to run with a process manager.
2) Use a PaaS like Heroku.
3) Use a serverless environment like Google Cloud Run.
You have many options and I'd explore them all!
I'm trying to create a simple Twitter bot to learn some Node.js skills.
It works fine on my local computer. I start the script with node bot.js and then close it with Ctrl + C.
I've uploaded the files to a server (Krystal hosting). I've ssh'd into the server and then used $ source /home/[username]/nodevenv/twitterbot/10/bin/activate. Which I think puts me into a Node environment (I'm not really clear what is happening here).
From here I can run node bot.js. My Twitter bot runs fine and I can leave the terminal. What I've realised now is that I don't know how to stop this script.
Can someone explain how I should be doing this? Is there a command I can enter to stop the original bot.js process? Since looking into this it looks like perhaps I should have used something like pm2 process manager. Is this correct?
Any pointers would be much appreciated.
Thanks,
B
You can kill it externally by nuking the process from an OS command line or in an OS GUI (exact procedure varies by OS). Ctrl-C from the shell is one version of this, but it can be done without the command shell that it was started in too by nuking the process directly.
Or, you can add a control port (a simple little http server running on a port only accessible locally) that accepts commands that let you do all sorts of things with the server such as extract statistics, shut it down, change the configuration, tell it to clear caches so content updates take effect immediately, etc... Shutting down the server this way allows for a more orderly shut-down from code within the server. You can even stop accepting incoming connections, but wait for existing http connections to complete before shutting down, close databases normally, etc...
Or, you can use a monitoring program such as PM2 or forever that in addition to restarting the server automatically if it should ever crash, they also offer commands for shutting it down too (which will just send it certain signals kind of like Ctrl-C does).
I am trying to stop a windows service that is using a port I need, but the service keeps restarting it self. How do I stop it from restarting itself?
I followed this question to kill it (How to kill the process currently using a port on localhost in windows?), but when I listen for the port again a new service started already:
How this happened and some notes:
I created a Nodejs service and started it as a windows service (so now it is running in it's own windows instance)
My service had a cmd line to stop it self net stop "Service Name". This semi-failed for some reason (it did stop, kinda, but then it starts again)
I have even uninstalled the Nodejs service completely, but still something is starting it up over and over (because the port stays in use)
I can't move the Nodejs service files, because they are in use
To find out what application/service the PID is referring to, you can open Resource Monitor by running: resmon
Then choose CPU tab and look for the PID, Note: it could be under Processes or Services. If it's a service then you can stop and disable it so it won't run again.
If it's a Process, the name should give you an idea what it is.
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.
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 &.