I'd like to check the status of an app registered with pm2 remotely such that other web-based monitoring services can give us a notification when something breaks.
Are there any options available to remotely check the status of a process in pm2 remotely? One possibility is to have a web script remotely eval() the pm2 status command and look for certain keywords, and make that script accessible on the web for the notification tool. This doesn't seem ideal, though, as we're using an eval command and maybe a regex of that output just to see what is going on.
Any advice?
I wrote a simple web interface for PM2.
You can simply start a websocket connection to /logs and get your application(s) stats updates such as status, uptime, cpu usage, memory usage, restarts in realtime.Feel free to use and contribute. Cheers!
https://github.com/doorbash/pm2-web
The best option is to use keymetrics. It's free to monitor upto 4 processes(great for development and side projects), easy to link an instance/server but quickly turns out to be very expensive when you scale up.
You could always try switching to other alternatives like upstart or pm2-gui.
Related
First time I am deploying a node.js/express server in production.
I am planning to deploy nodemon. Log a number of metrics through node middleware, such as timing, number of requests, what endpoints?
Anything anyone uses for my use case?
use pm2 instead of nodemon, it stores the logs in a file instead of displaying to window, and you can use pm2 logs to see the logs.
use morgan to log req metrics
I recommend pm2 as a deployment manager, it has many features like "cluster mode" and "log manager", you can see more about this on this page:
http://pm2.keymetrics.io/docs/usage/log-management/
I also recommend that for projects in the production environment, you only handle the error and alerts logs, because the performans of your application is affected by them.
Of course pm2 also has options to handle this, and you can define the events to be in your logs.
please see the advantages that pm2 has.
I have a system-V init service/daemon running my application. I wanted to make sure that my application always runs even with conditions where process/service could crash, machine restart. I know of supervisord which is able to monitor process but I am not sure it can monitor service/daemon ?
Looks like the manual advices against it.
There is an answer to a similar question which provides a workaround.
Anyway, I would try to find a way to have that service stay in the foreground.
I have multiple node.js apps running at my VPS, and I access to it through ssh. Right now I start them in the way:
nohup node server.js
That looks good but I get whole logs to nohup.out, and what's more important and not efficient is about restarting of stopping them.
If I do ps -A | grep node I will get an output like:
9172 ? 00:00:01 node
9178 ? 00:00:00 node
...
So, how can I identify them?
I also knew about nodemon and it's great! But however logging out ssh breaks the magic.
I think maybe some more advanced tools would help out. What's the best approach for this?
Just in case, I use Nginx on top (port 80) and do reverse proxy, but I'd be ok changing that.
One solution (there are many) is pm2: https://github.com/Unitech/pm2
It's a process manager for node, and comes with a variety of features, some of which include the ability to spread your app across multiple CPU cores while providing an easy TTY management view of the applications. It also has the ability to reload the apps without stopping them.
If the readme's not sufficient, I found this post useful in understanding the basics: http://devo.ps/blog/2013/06/26/goodbye-node-forever-hello-pm2.html
You can run nodemon under --quiet mode and it'll suppress all nodemon output (and keep your logging working).
I am looking for a solution that monitors a service on a server and runs a custom script when a problem is found.
To be more specific:
We have a service that relies on many Elastic IPs at EC2, when a problem occurs on the primary server, all those EIPs are required to move to a slave server.
I have written the script for the EIP failover, but my company wants to use an open source tool for the monitoring part.
I have looked into pacemaker/heartbeat solution but it seems too complex for what i want to achieve.
Please help me find a good solution for this problem, thanks in advance!
If your problem is as simple as watching a process and trigger scripts, monit will be your best friend:
http://mmonit.com/monit/
The good thing about monit is that it scales well if you have a lot of servers as it runs and executes everything locally on the machine being monitored.
Have you considered using Scout ? It allows you to write your custom scripts that get executed after triggers. For example you can setup a trigger from a third server that when it can't reach one of your EIPs then it's time to do the EIP switchover.
We are currently monitoring all of our servers using Scout and are pretty happy.
I am a node.js developer. I use Amazon ec2 to deploy my node.js apps.
I want to have my node.js service running permanently - restarted if it fails for any reason.
I came across 2 tools . Forever and Upstart
Is there any advantages of using one over the other ?
Is there any other tool which is better ?
Upstart is a system service controller, similar to SysV Init and will start/stop/restart essentially any service registered for it, Node.js-based or not, and it will also automatically start services on system start for you. But Upstart is essentially specific to Ubuntu, and Upstart-specific services won't run on other Linux distros.
Upstart has a SysV Init compatibility layer that you could target,instead, to maintain as broad of a compatibility layer as possible.
Forever is a Node.js application that monitors and restarts other Node.js applications as needed, and as defined by its configuration JSON. Lots of options and fine-grained control over your service without the effort that would be needed to duplicate it in a custom SysV Init script. However, Forever isn't a system service, so if the server is restarted, you'll have to manually start your forever scripts again.
Beyond that, if all you need is something that will restart your script if/when it crashes, and you don't care about it starting automatically on system start, all you need is a bash script as simple as:
#!/bin/bash
while true
do
node ./myScript.js
done
Just to correct a misleading statement in the accepted answer...it is not true that upstart is an Ubuntu-only technology. See:
https://serverfault.com/questions/291546/centos-6-and-upstart
http://searchenterpriselinux.techtarget.com/tip/RHEL-6-ditches-System-V-init-for-Upstart-What-Linux-admins-need-to-know
http://en.wikipedia.org/wiki/Upstart#Adoption
With that, I think it is a much more compelling solution.