This may be a stupid question, sorry.
But I SSH into a server and run my node server with the command:
node server.js
I note however that if my SSH sessions stops abruptly (internet cuts out etc) then I am confronted with an error. Network error unexpectedly closed session or something similar.
I then note that my node server has actually stopped. However nothing has actually gone wrong. It was as if I had Ctrl + C'd but otherwise I simply timed out from my SSH session.
So clearly I'm doing something wrong. Is there a way to ssh in, run the serve rand disconnect without the server turning itself off or similar? Or to avoid my SSH session collapsing and taking the server with it?
Assuming you are not on Windows, you can just start it without a console like this:
node server.js &
And, then it won't be wired into your ssh console.
Or, you can use something like forever to launch node as its own process and then monitor it and auto-restart it.
forever server.js
Lots more info here.
Related
I have a raspberry PI on which I run a node server. To start and control the terminal on which the server runs I use desktop remote to remote control the raspberry. Now this method is really slow so I was wondering, since I only need a command line anyway if I couldn't just connect to my raspberry pi using ssh for example.
My question now, would be if I do so, can I navigate to my node folder, run my node file and then close the ssh connection? Will my Node server keep running and if so how would I access the terminal with the node session after closing the connection?
The easiest way to do this is something like:
nohup node myapp.js &
This will make the app run in the background, and nohup prevents it from stopping when the connection closes.
This is a cheap and quick way to do this. A more appropriate way might be one of the following:
Using something like docker to manage running applications.
Using something like supervisord to do the same thing.
Writing scripts for initd and turn it into a real 'service'.
Changing the node application to fork & deamonize itself.
I have never set up a server before but since Parse announced that they are closing down I thought I might give it a shot. I have followed along with this tutorial and have managed to migrate my Parse database across to digital ocean.
When I call npm run start everything works fine. I can query for data and create new objects all from my iOS app. But there is just one problem. How do I keep the server up and running even when terminal is not running from my Mac.
When I call npm run start this is what gets logged in terminal:
> parse-server-example#1.0.0 start /var/www/parse
> node index.js
[TypeError: Cannot read property 'Kerberos' of undefined]
DATABASE_URI not specified, falling back to localhost.
parse-server-example running on port 1337.
I know that this is probably a noob question and yes my knowledge is quite limited, so if you could help me then that would be great!
Thanks for your time!
Okay so I have just found the answer after posting a question on the Digital Ocean question page, instead of running npm run start I should have been doing nohup npm start &
use screen to create a new session https://tournasdimitrios1.wordpress.com/2010/11/04/linux-the-screen-command-a-must-for-ssh/
start your server
detach session
return to running session when needed
+1 to Lev for his answer, I don't have enough reputation to upvote his answer.
Another option is tmux, like screen, you create a session then start your app and detach when done and your app will continue to run.
I see this document can help you. https://www.npmjs.com/package/forever. I tried in window. It is OK.
Those are my comment
*** Run background code with schedule
Linux: nohup file-nodejs.js &
Window:
Install forever: npm install forever -g
Start/Stop : forever start file-nodejs.js | forever stop file-nodejs.js (restartall | restart | stopall)
Reference : https://www.npmjs.com/package/forever
I'm using Amazon WS to test some rudimentary nodejs server. The problem I'm having is that when I close the putty command prompt on my PC, that I can not reach the server anymore with a browser.
Ive read about forever and forever-monitor. I'n not sure why the script must be restarted constantly, but ok let's assume it must.
I'm using both
forever "/home/ec2-user/myApp.js"
and
node "/home/ec2-user/foreverMonitor.js"
(The latter has the myApp.js reference in the foreverMonitor.js file. Similar to Where place forever-monitor code?.)
Both do start the server, but when I close putty, both also let the server die.
What am I missing here?
------------------------------------- update -------------------------------------
I guess I can also skip foreverMonitor (not verified yet)
nohup forever "/home/ec2-user/myApp.js" &
forever stop "/home/ec2-user/myApp.js"
------------------------------------- update -------------------------------------
working, now using this
nohup forever "/home/ec2-user/foreverMonitor.js" &
forever stop "/home/ec2-user/foreverMonitor.js"
I'm not totally familiar with AWS, but it seems that you probably need to run nohup. The trailing ampersand should give you control of the terminal again immediately after executing the command.
$ nohup forever "/home/ec2-user/myApp.js" &
$ nohup node "/home/ec2-user/foreverMonitor.js" &
See this answer for more details on nohup and the trailing ampersand: https://stackoverflow.com/a/15595391/498624
Have a look at PM2 https://github.com/Unitech/pm2
After using forever successfully, I switched to PM2.
forever works fine but I found PM2 was a better fit to my mental model. PM2 also has a very neat (and repidly evolving) Web interface where you can monitor and control node instances. As a bonus you can also run non-node tasks under PM2
I wasn't quite sure what to call this question but here i go:
i have a remote server where i have installed node.js now normally this would be how i start the server:
ssh root#ip
cd /var/www/mydomain/server
nodejs server.js
This works without any issues however what happens when i close down the terminal? How can i make sure that the server doesn't just stop. And how can i control it after i have started it (for instance restarting / stopping it).
There are plenty of solutions here, but maybe the most easy to start with is using forever.
Forever is a npm module that keep your app running and restarts it if it crashes.
Also there are more advanced solutions, like using PM2, which I recommend, but first take a look at forever.
As you can tell by my question, I'm new to this...
I built my first website, I set up my first Node.js server to serve it and then pushed everything live on EC2.
I tested everything on my EC2 IP address and everything seems to be working.
Now up until now, I've been testing my app locally so it makes sense that whenever I closed the terminal, app.js would stop running so nothing would be served on localhost.
Now that my server is on EC2, the same thing happens ("obviously" one could say..) whenever I close my terminal.
So my question is how do I keep my Node.js server running on EC2 for like... forever..so that my site stays live.. forever :)
I read something about a node module called "forever" but I'm wondering (being new and all..) why isn't this "forever" functionality a default setting of the Node.js-EC2 system ?
I mean, correct me if I'm wrong, but isn't the whole point of setting up a web server and pushing it live to have it stay live forever? Isn't that what servers are supposed to do anyway (infinitely listening for requests) ? And if that's the case why do we need extra modules/settings to achieve that ?
Thanks for your help.. As you can tell I'm not only looking for a solution but an explanation as well because I got really confused.. :-)
EDIT (a few details you might need) - After installing my app on EC2 these are the steps that I follow on the terminal (The app is running on Amazon Linux by the way) :
I type ssh -i xxxxxxxxxxx.pem ec2-user#ec2-xx-xx-xx-x.eu-west-1.compute.amazonaws.com on the
terminal
After logging onto the Amazon machine I then go to the relevant folder and execute node app.js
There are 3 folders in the machine : node, node_modules and *name of my app*
app.js resides in *name of my app*
After that, the site goes live on my EC2 IP
Once I close the terminal, everything is switched off
Before you invoke Node.js, run the command:
screen
This will create a persistent environment which will allow your process to keep running after you disconnect.
When you reconnect, you can use this command to reconnect to that environment:
screen -r
Here's a random link to learn more about screen:
http://www.rackaid.com/blog/linux-screen-tutorial-and-how-to/
However, this won't help you if your EC2 instance restarts. There are many different ways to do that. Adding your startup command to /etc/rc.local is one way. Here's a link to an Amazon guide which includes adding something to /etc/rc.local.
http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/building-shared-amis.html
I worked with the valid answer for a while but some times the screen just end with no reason also screen has no balance loader and others features that in a production enviroment you should care , Currently I use a npm component to do this job.
https://www.npmjs.com/package/pm2
This is so easy to use.
$ npm install pm2 -g
then just start your app with pm2 like this
$ pm2 start app.js
In the above link you can find diferents tasks to perform if you need.
Hope this help the newbies like me.
There's a better way. Use forever.js.
See it here: https://github.com/foreverjs/forever
This is a nice tutorial for how to use chkconfig with forever on CENTOS.
http://aronduby.com/starting-node-forever-scripts-at-boot-w-centos/
Or use tmux
Just Enter a tmux screen run node server
Ctrl+b Hit D and you're done.
I am very late to join the thread and seems its basic problem with every newbie. Follow the below to setup properly your first server.
follow the step on the ec2 instance(before doing this make sure you have a start script for pm2 in your package.json file):
npm install pm2 -g
pm2 startup systemd
See the output and at the last line it must be like..
You have to run this command as root. Execute the following command:
sudo env PATH=$PATH:/usr/bin /usr/lib/node_modules/pm2/bin/pm2 startup
systemd -u sammy --hp /home/sammy
Take the last line command and run again with root privilege.
(before running the next command, Provide a new start script for pm2 in your package.json file e.g: "pm2-start": "pm2 start ./bin/www")
npm run pm2-start
for more info follow the link.
https://www.digitalocean.com/community/tutorials/how-to-set-up-a-node-js-application-for-production-on-ubuntu-16-04
If you are using a Ubuntu EC2, better to use the following we have been using this for the past 6 years and have had no issues with this.
sudo npm i -g forever
Now start your main, example
forever start index.js
forever start src/server.js
To stop the server use the following command
forever stop index.js
To list multiple servers running forever
forever listall