Running very high volume traffic on these servers configured with django, gunicorn, supervisor and nginx. But a lot of times I tend to see 502 errors. So I checked the nginx logs to see what error and this is what is recorded: [error] 2388#0: *208027 connect() to unix:/tmp/gunicorn-ourapp.socket failed (11: Resource temporarily unavailable) while connecting to upstream Can anyone help debug what might be causing this to happen? This is our nginx configuration: sendfile on; tcp_nopush on; tcp_nodelay off; listen 80 default_server; server_name imp.ourapp.com; access_log /mnt/ebs/nginx-log/ourapp-access.log; error_log /mnt/ebs/nginx-log/ourapp-error.log; charset utf-8; keepalive_timeout 60; client_max_body_size 8m; gzip_types text/plain text/xml text/css application/javascript application/x-javascript application/json; location / { proxy_pass http://unix:/tmp/gunicorn-ourapp.socket; proxy_pass_request_headers on; proxy_read_timeout 600s; proxy_connect_timeout 600s; proxy_redirect http://localhost/ http://imp.ourapp.com/; #proxy_set_header Host $host; #proxy_set_header X-Real-IP $remote_addr; #proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for; #proxy_set_header X-Forwarded-Proto $my_scheme; #proxy_set_header X-Forwarded-Ssl $my_ssl; } We have configure Django to run in Gunicorn as a generic WSGI application. Supervisord is used to launch the gunicorn workers: home/user/virtenv/bin/python2.7 /home/user/virtenv/bin/gunicorn --config /home/user/shared/etc/gunicorn.conf.py daggr.wsgi:application This is what the gunicorn.conf.py looks like: import multiprocessing bind = 'unix:/tmp/gunicorn-ourapp.socket' workers = multiprocessing.cpu_count() * 3 + 1 timeout = 600 graceful_timeout = 40 Does anyone know where I can start digging to see what might be causing the problem? This is what my ulimit -a output looks like on the server: core file size (blocks, -c) 0 data seg size (kbytes, -d) unlimited scheduling priority (-e) 0 file size (blocks, -f) unlimited pending signals (-i) 59481 max locked memory (kbytes, -l) 64 max memory size (kbytes, -m) unlimited open files (-n) 50000 pipe size (512 bytes, -p) 8 POSIX message queues (bytes, -q) 819200 real-time priority (-r) 0 stack size (kbytes, -s) 8192 cpu time (seconds, -t) unlimited max user processes (-u) 1024 virtual memory (kbytes, -v) unlimited file locks (-x) unlimited