My Django application run well for a while, then I got 502 Bad Gateway, after a few hours, I am unable to ping the domain and use SSH to connect my server(from Amazon Lightsail). My other application served by ngnix was also not available then. While if I didn't start the Django application, ther application served by ngnix would run steadily. So I guess it is the error of my Django application crashed ngnix and the server.
After rebooting the server for serveral times, the server seems recovered then I can ping the domain and use SSH to connect the server. But after a while, the same problem would occurs again. I wonder how to fix the problem.
Some diagnostic information since the start of the Django application to the end of the Nginx server provided below.
The RAM usage is high during the process.
The uwsgi log. https://bpa.st/FP7Q
The Nginx error log. https://bpa.st/35EQ
Related
I'm a complete newbie when it comes to networking. I have two PCs on my LAN both running Manjaro. My main aim is to test functionality on a Django server running on one PC, from the other. I am running the Django server on the PC with ip address 192.168.1.138 using the command
python manage.py runserver 192.168.1.138:8000
and in settings.py
ALLOWED_HOSTS = ['localhost', '192.168.1.138']
I can ping 192.168.1.138 from the client PC, and ping the client PC from the server PC. But if I enter the ip address/port into the browser, it fails with
took too long to respond
I don't know if this a separate problem or a manifestation of the first, but when I run NitroShare, I am able to 'see' the PC running the Django server from the PC acting as the client, but if I try to transfer a file, again it times out. I am unable to see the client from the server in NitroShare.
Any suggestions or help gratefully received
Ensure you don't have a firewall running (or that it allows connections to port 8000). Manjaro's docs imply there might be no firewall by default, but in case there is, see https://wiki.manjaro.org/index.php?title=Firewalls
Set ALLOWED_HOSTS = ['*'], don't bother with limiting them.
Run with python manage.py runserver 0:8000 ; the 0 stands for 0.0.0.0, i.e. has the server listening on all network interfaces.
First I would scan with the other PC the open ports of you "Server"-PC, you can do that with tools like Nmap. Make sure you opened the ports of your "Server"-PC at your router interface. Another option could be the launching of the django app in a docker container. Here's the link of the official docker image at DockerHub:
https://hub.docker.com/_/django
I am working on a flask-socketio server which is getting stuck in a state where only 504s (gateway timeout) are returned. We are using AWS ELB in front of the server. I was wondering if anyone wouldn't mind giving some tips as to how to debug this issue.
Other symptoms:
This problem does not occur consistently, but once it begins happening, only 504s are received from requests. Restarting the process seems to fix the issue.
When I run netstat -nt on the server, I see many entries with rec-q's of over 100 stuck in the CLOSE_WAIT state
When I run strace on the process, I only see select and clock_gettime
When I run tcpdump on the server, I can see the valid requests coming into the server
AWS health checks are coming back succesfully
EDIT:
I should also add two things:
flask-socketio's server is used for production (not gunicorn or uWSGI)
Python's daemonize function is used for daemonizing the app
It seemed that switching to gunicorn as the wsgi server fixed the problem. This legitimately might be an issue with the flask-socketio wsgi server.
I have a Django project running using gunicorn sock(not port).
I am using supervisor to run it. The problem is - supervisor is saying that the process is running. Logs doesnt show anything.
But site says "Bad gateway". Nginx generally shows bad gateway when the gunicorn is not running. But here, gunicorn is running without errors but nginx shows bad gateway.
If it uses port, I would have tested locally using "wget http://localhost:8000" but since we use sock here, how to test if its really running and why its not showing any error.
I have a Django site that uses Gunicorn and Nginx. Occasionally, I'll have a problem that I need to debug. In the past, I would shut down Gunicorn and Nginx, go to my Django project directory and start the Django development server ("python ./manage.py runserver 0:8000"), and then restart Nginx. I could then insert set_trace() commands and do my debugging. When I fixed the problem I'd shut down Nginx and then restart Gunicorn and Nginx. I'm pretty sure this was working.
Recently, though, I've begun having problems. What happens now is that when I've stopped at a breakpoint, after a couple of minutes the web page that I've stopped on will change and display "404 Not Found" and if I take another step in the debugger, I'll see this error:
- Broken pipe from ('127.0.0.1', 43742)
This happens on my development, staging, and production servers which I'm accessing via their domain names, e.g. "web01.example.com" (not really example).
What is the correct way to debug my Django application on my remote servers?
Thanks.
I figured out the problem. First I observed that when I stopped at a breakpoint, the page always timed out after exactly one minute which suggested that the Nginx connection to the web server was timing out if the web server took more than 60 seconds to respond. I then found an Nginx proxy_read_timeout directive which defines this timeout. Then it was merely a matter of changing the length of the timeout in my Nginx config file:
# /etc/nginx/sites-enabled/example.conf
http {
server {
...
location #django {
...
# Set timeout to 1 hour
proxy_read_timeout 3600s;
...
}
...
}
}
Once you've made this change you need to reload Nginx, not restart it, in order to this change to take effect. Then you start Django as I indicated above and you can now debug your Django application without it timing out. Just be sure to remove the timeout setting when you're done debugging, reload Nginx again, and restart Gunicorn.
I have used nginx as web server for django project , And now i want to use my normal django local server (switch to older local server).
I tried
sudo service nginx stop
(It is showing nginx is stopped)
i killed all process too.
But still my localserver:127.0.0.1:8000 is under nginx control.And my computer ip is also under nginx control.(it shows the nginx default page)
I want free that particular port(localserver:127.0.0.1:8000). How can i completely stop nginx ?