[SOLVED] Troubleshooting app restarts

help
1

I have a meteor application running in production with Phusion Passenger. When I check the error logs it looks like the app is restarting every couple of minutes. How can I start troubleshooting this?

Partial log example:
…
[ N 2018-10-02 12:01:15.5881 13634/T7 age/Cor/CoreMain.cpp:994 ]: Checking whether to disconnect long-running connections for process 27312, application /var/www/vhosts/myapp/live (production)
App 28045 stdout:
App 28045 stderr: Note: you are using a pure-JavaScript implementation of bcrypt.
App 28045 stderr: While this implementation will work correctly, it is known to be
App 28045 stderr: approximately three times slower than the native implementation.
App 28045 stderr: In order to use the native implementation instead, run
App 28045 stderr:
App 28045 stderr: meteor npm install --save bcrypt
App 28045 stderr:
App 28045 stderr: in the root directory of your application.
…

The only reason I’m recognising the app is restarting is because of the bcrypt message that only appears during startup. Also users say the app is sometimes slow, I guess this is when they are waiting during the restart.

2

What happens if you install the native bcrypt? I am running Passenger and don’t have that problem. What version and OS are you on? Passenger native or as nginx module?

3

The problem is not so much about the bcrypt message, it’s ok that the slightly slower bcrypt is used. It’s just that I know whenever I see that message I know the app has just started and I see the message sometimes every 5 minutes.

4

To make sure that your app restarted, try to add a script in Meteor.startup function, which writes some logs.

1 Like
5

In case anyone else runs into this problem, it was caused by a different version of node on the server, which was causing segmentation vaults:

/var/log/messages:
Oct 5 15:26:37 hosting212 kernel: traps: Passenger NodeA[10337] general protection ip:207359b45792 sp:7f7db0e8ebf0 error:0
Oct 5 15:26:37 hosting212 abrt-hook-ccpp: Process 10337 (node) of user 10028 killed by SIGSEGV - dumping core

Local development version:
$ meteor node --version
v8.11.3

On the server:
$ node --version v8.11.1

After installing node v8.11.3 on the server everything is running smooth again.