monit和unicorn restart命令在Rails 5.2应用程序中不起作用

Question

我将Monit配置为监视独角兽，并在内存超出或cpu增加到某个限制以上时重新启动它，

无论何时发生，monit都不会重新启动unicorn，这是我在monit日志文件中找到的日志

[UTC Aug 11 20:15:41] error    : 'unicorn_myapp' failed to restart (exit status 127) -- '/etc/init.d/unicorn_myapp restart': /etc/init.d/unicorn_myapp: 27: kill: No such process

Couldn't reload, starting 'cd /home/ubuntu_user/apps/myapp/current;  bundle exec unicorn -D -c /home/ubuntu_user/apps/myapp/shared/config/unicorn.rb -E pr
[UTC Aug 11 20:16:11] error    : 'unicorn_myapp' process is not running
[UTC Aug 11 20:16:11] info     : 'unicorn_myapp' trying to restart
[UTC Aug 11 20:16:11] info     : 'unicorn_myapp' restart: '/etc/init.d/unicorn_myapp restart'
[UTC Aug 11 20:16:42] error    : 'unicorn_myapp' failed to restart (exit status 127) -- '/etc/init.d/unicorn_myapp restart': /etc/init.d/unicorn_myapp: 27: kill: No such process

Couldn't reload, starting 'cd /home/ubuntu_user/apps/myapp/current;  bundle exec unicorn -D -c /home/ubuntu_user/apps/myapp/shared/config/unicorn.rb -E pr
[UTC Aug 11 20:17:12] error    : 'unicorn_myapp' process is not running
[UTC Aug 11 20:17:12] info     : 'unicorn_myapp' trying to restart
[UTC Aug 11 20:17:12] info     : 'unicorn_myapp' restart: '/etc/init.d/unicorn_myapp restart'
[UTC Aug 11 20:17:42] error    : 'unicorn_myapp' failed to restart (exit status 127) -- '/etc/init.d/unicorn_myapp restart': /etc/init.d/unicorn_myapp: 27: kill: No such process

Couldn't reload, starting 'cd /home/ubuntu_user/apps/myapp/current;  bundle exec unicorn -D -c /home/ubuntu_user/apps/myapp/shared/config/unicorn.rb -E pr
[UTC Aug 11 20:18:12] error    : 'unicorn_myapp' process is not running

这是我在/etc/monit/conf.d/下的/etc/monit/conf.d/配置

check process unicorn_myapp
  with pidfile /home/ubuntu_user/apps/myapp/current/tmp/pids/unicorn.pid
  start program = "/etc/init.d/unicorn_myapp  start"
  stop program = "/etc/init.d/unicorn_myapp  stop"
  restart program = "/etc/init.d/unicorn_myapp  restart"
  if not exist  then restart
  if mem is greater than 300.0 MB for 2 cycles then restart       # eating up memory?
  if cpu is greater than 50% for 4 cycles then restart                  # send an email to admin
  if cpu is greater than 80% for 30 cycles then restart                # hung process?
  group unicorn

当发生此类错误并中断应用程序时，应重新启动独角兽

从unicorn.log file

ERROR -- : Cannot allocate memory - fork(2) (Errno::ENOMEM)

当我从终端运行/etc/init.d/unicorn_myapp重新启动时

Answer 1

Monit通常使用重新启动程序来启动程序。 我不知道为什么会这样，但是我也观察到了这种现象。

只需注释掉“重新启动”行即可。 这应该强制monit运行启动脚本，而不应该尝试终止现有进程。

您可能还想观看您的日志文件，例如

CHECK FILE unicorn_log PATH log__file__path___change_me_or_the_world_will_flatten
    start program = "/etc/init.d/unicorn_myapp start"
    stop  program = "/etc/init.d/unicorn_myapp stop"

    # No log File entry for one hour? 
    if timestamp is older than 1 hour then restart

    # Allocate Memery error?
    if content = "Cannot allocate memory" then restart