id	summary	reporter	owner	description	type	status	priority	milestone	component	version	resolution	keywords	cc	uname	nginx_version
2150	comments in systemd documents may use the wrong signal	lisbethw1130@…		"In ubuntu 20.04, nginx use systemd to control status of nginx, the following is part of the /lib/systemd/system/nginx.service

    # ExecStop sends SIGSTOP (graceful stop) to the nginx process.
    # If, after 5s (--retry QUIT/5) nginx is still running, systemd takes control
    # and sends SIGTERM (fast shutdown) to the main process.
    # After another 5s (TimeoutStopSec=5), and if nginx is alive, systemd sends
    # SIGKILL to all the remaining processes in the process group (KillMode=mixed).

    [Service]
    Type=forking
    PIDFile=/run/nginx.pid
    ExecStartPre=/usr/sbin/nginx -t -q -g 'daemon on; master_process on;'
    ExecStart=/usr/sbin/nginx -g 'daemon on; master_process on;'
    ExecReload=/usr/sbin/nginx -g 'daemon on; master_process on;' -s reload
    ExecStop=-/sbin/start-stop-daemon --quiet --stop --retry QUIT/5 --pidfile /run/nginx.pid
    TimeoutStopSec=5

As comment said, execstop will send SIGSTOP, and SIGTERM after 5 seconds if process don't stop, but actually the command below use SIGQUIT instead of SIGSTOP to gracefully shutdown the process.

then I looked for the nginx documentation http://nginx.org/en/docs/control.html , nginx receive QUIT instead of STOP.

also, refrring to the linux signal(7) https://man7.org/linux/man-pages/man7/signal.7.html

The signals SIGKILL and SIGSTOP cannot be caught, blocked, or ignored.

nginx shouldn't be able to capture SIGSTOP and take time to gracefully shutdown, SIGQUIT can

the comments above should change to

ExecStop sends **SIGQUIT** (graceful stop) to the nginx process.


If there's anything I missed it, pls let me know, thanks"	defect	closed	minor		nginx-package	1.18.x	invalid		lisbethw1130@…	Linux ip-10-0-3-118 5.4.0-1024-aws #24-Ubuntu SMP Sat Sep 5 06:17:48 UTC 2020 aarch64 aarch64 aarch64 GNU/Linux	"nginx version: nginx/1.18.0 (Ubuntu)
built with OpenSSL 1.1.1f  31 Mar 2020
TLS SNI support enabled
configure arguments: --with-cc-opt='-g -O2 -fdebug-prefix-map=/build/nginx-WUOw6x/nginx-1.18.0=. -fstack-protector-strong -Wformat -Werror=format-security -fPIC -Wdate-time -D_FORTIFY_SOURCE=2' --with-ld-opt='-Wl,-Bsymbolic-functions -Wl,-z,relro -Wl,-z,now -fPIC' --prefix=/usr/share/nginx --conf-path=/etc/nginx/nginx.conf --http-log-path=/var/log/nginx/access.log --error-log-path=/var/log/nginx/error.log --lock-path=/var/lock/nginx.lock --pid-path=/run/nginx.pid --modules-path=/usr/lib/nginx/modules --http-client-body-temp-path=/var/lib/nginx/body --http-fastcgi-temp-path=/var/lib/nginx/fastcgi --http-proxy-temp-path=/var/lib/nginx/proxy --http-scgi-temp-path=/var/lib/nginx/scgi --http-uwsgi-temp-path=/var/lib/nginx/uwsgi --with-debug --with-compat --with-pcre-jit --with-http_ssl_module --with-http_stub_status_module --with-http_realip_module --with-http_auth_request_module --with-http_v2_module --with-http_dav_module --with-http_slice_module --with-threads --with-http_addition_module --with-http_gunzip_module --with-http_gzip_static_module --with-http_image_filter_module=dynamic --with-http_sub_module --with-http_xslt_module=dynamic --with-stream=dynamic --with-stream_ssl_module --with-mail=dynamic --with-mail_ssl_module
"