nginx crashed

[bobykus@…]

Server crashing periodically

tail -f /var/log/nginx/error.log | grep signal
2016/10/05 14:09:58 [notice] 7463#0: signal 15 (SIGTERM) received, exiting

Debian GNU/Linux 8 \n \l

dpkg -l | grep nginx
ii nginx 1.6.2-5+deb8u2 all small, powerful, scalable web/proxy server
ii nginx-common 1.6.2-5+deb8u2 all small, powerful, scalable web/proxy server - common files
ii nginx-full 1.6.2-5+deb8u2+b1 amd64 nginx web/proxy server (standard version)
ii nginx-full-dbg 1.6.2-5+deb8u2+b1 amd64 nginx web/proxy server (standard version) - debugging symbols

Here is core dump backtrace

gdb /usr/sbin/nginx /tmp/core-nginx-11-33-33-9530-1475669436

GNU gdb (Debian 7.7.1+dfsg-5) 7.7.1
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Reading symbols from /usr/sbin/nginx...Reading symbols from /usr/lib/debug/.build-id/d2/c82927fb61b1497e9123e35f6db0aee695a6a1.debug...done.
done.
[New LWP 9530]
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
Core was generated by `nginx:'.
Program terminated with signal SIGSEGV, Segmentation fault.
#0 0x00007f6612080be3 in epoll_wait_nocancel () at ../sysdeps/unix/syscall-template.S:81
81 ../sysdeps/unix/syscall-template.S: No such file or directory.
(gdb) bt
#0 0x00007f6612080be3 in epoll_wait_nocancel () at ../sysdeps/unix/syscall-template.S:81
#1 0x000000000042b921 in ngx_epoll_process_events (cycle=0x890a20, timer=500, flags=0) at src/event/modules/ngx_epoll_module.c:579
#2 0x0000000000422737 in ngx_process_events_and_timers (cycle=cycle@entry=0x890a20) at src/event/ngx_event.c:248
#3 0x0000000000429a4a in ngx_worker_process_cycle (cycle=cycle@entry=0x890a20, data=data@entry=0x0) at src/os/unix/ngx_process_cycle.c:816
#4 0x00000000004283fa in ngx_spawn_process (cycle=cycle@entry=0x890a20, proc=proc@entry=0x429990 <ngx_worker_process_cycle>, data=data@entry=0x0, name=name@entry=0x4ac11e "worker process",

respawn=respawn@entry=-3) at src/os/unix/ngx_process.c:198

#5 0x0000000000429c84 in ngx_start_worker_processes (cycle=0x890a20, n=2, type=-3) at src/os/unix/ngx_process_cycle.c:364
#6 0x000000000042aa4b in ngx_master_process_cycle (cycle=0x890a20) at src/os/unix/ngx_process_cycle.c:136
#7 0x0000000000408b13 in main (argc=<optimized out>, argv=<optimized out>) at src/core/nginx.c:407
(gdb)

here is config

cat /etc/nginx/nginx.conf
user www-data;
pid /var/run/nginx.pid;
worker_processes 2;
worker_cpu_affinity 01 10;
timer_resolution 50ms; # Save gettimeofday calls
worker_rlimit_nofile 131072;

error_log /var/log/nginx/error.log info;
#error_log /var/log/nginx/error.log debug;

#addint to enable core dump
worker_rlimit_core 500M;
working_directory /tmp/;

events {

worker_connections 20000;
multi_accept on;

}

mail {

server_name mail.some.com;
resolver off;
auth_http 127.0.0.1:1080/mail-auth;
auth_http_timeout 60s;

proxy_pass_error_message on;
proxy_timeout 6h;

imap_auth login plain cram-md5;
imap_capabilities IMAP4rev1 LITERAL+ SASL-IR LOGIN-REFERRALS ID ENABLE IDLE;

pop3_auth plain cram-md5 apop;
pop3_capabilities CAPA TOP UIDL RESP-CODES PIPELINING USER;

smtp_auth login plain cram-md5;
smtp_capabilities ETRN ENHANCEDSTATUSCODES 8BITMIME DSN "SIZE 52428800";

ssl_certificate /etc/nginx/ssl/STAR.some.com.full;
ssl_certificate_key /etc/nginx/ssl/STAR.some.com.key;
ssl_session_cache shared:SSL:50m;
ssl_session_timeout 15m;
ssl_session_tickets on;

# modern configuration. tweak to your needs.
# Outlook 2010 only supports TLSv1
ssl_protocols TLSv1 TLSv1.1 TLSv1.2;
ssl_ciphers 'ECDHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-AES256-GCM-SHA384:DHE-RSA-AES128-GCM-SHA256:DHE-DSS-AES128-GCM-SHA256:kEDH+AESGCM:ECDHE-RSA-AES128-SHA256:ECDHE-ECDSA-AES128-SHA256:ECDHE-RSA-AES128-SHA:ECDHE-ECDSA-AES128-SHA:ECDHE-RSA-AES256-SHA384:ECDHE-ECDSA-AES256-SHA384:ECDHE-RSA-AES256-SHA:ECDHE-ECDSA-AES256-SHA:DHE-RSA-AES128-SHA256:DHE-RSA-AES128-SHA:DHE-DSS-AES128-SHA256:DHE-RSA-AES256-SHA256:DHE-DSS-AES256-SHA:DHE-RSA-AES256-SHA:!aNULL:!eNULL:!EXPORT:!DES:!RC4:!3DES:!MD5:!PSK';
ssl_prefer_server_ciphers on;
ssl_dhparam /etc/nginx/ssl/dhparam.pem;

server {

listen 110;
starttls on;
protocol pop3;

}
server {

listen 995;
ssl on;
protocol pop3;

}
server {

listen 143;
starttls on;
protocol imap;

}
server {

listen 993;
ssl on;
protocol imap;

}
server {

listen 587;
starttls on;
protocol smtp;

}
server {

listen 465;
starttls on;
protocol smtp;

}

}

http {

server {

listen 0.0.0.0:80;
server_name mail.some.com;
server_tokens off;
return 301 ​https://webmail.some.com/;

[Maxim Dounin]

Please try to reproduce the problem without any 3rd party modules compiled in.

[bobykus@…]

I am very sure nginx does not have any 3rd party modules compiled in but the ones coming with deb package. What exactly modules you mean?

[Valentin V. Bartenev]

Replying to bobykus@…:

I am very sure nginx does not have any 3rd party modules compiled in but the ones coming with deb package. What exactly modules you mean?

These are the 3rd-party modules compiled in:

--add-module=/build/nginx-ryOGNl/nginx-1.6.2/debian/modules/nginx-auth-pam --add-module=/build/nginx-ryOGNl/nginx-1.6.2/debian/modules/nginx-dav-ext-module --add-module=/build/nginx-ryOGNl/nginx-1.6.2/debian/modules/nginx-echo --add-module=/build/nginx-ryOGNl/nginx-1.6.2/debian/modules/nginx-upstream-fair --add-module=/build/nginx-ryOGNl/nginx-1.6.2/debian/modules/ngx_http_substitutions_filter_module

The fact that they are coming with the deb package you are using does not make them official nor improves their stability.

[Maxim Dounin]

Feedback timeout.