Runit: process monitoring made easy

Install:

 apt-get install -y runit

# Setup the application's runit directory

/etc/sv/application:
file.directory:
- mode: 0755
- user: someuser
- group: someuser
- recurse:
- user
- group
- mode
 


# Create the application's runit run script

/etc/sv/application/run:

file.managed:
- name: /etc/sv/application/run
- template: jinja
- user: someuser
- group: someuser
- source: salt://unicorn/templates/sv-unicorn-run.jinja
- context:
unicorn_command: unicorn_rails
unicorn_environment: vagrant
 

# Create the application's runit log run script

/etc/sv/application/log/run:
file.managed:
- name: /etc/sv/application/log/run
- user: someuser
- group: someuser
- source: salt://runit/templates/sv-log-run
 

# Create the log directory
/etc/sv/application/log/main:
file.directory:
- user: someuser
- group: someuser
- makedirs: True
 

# Create the supervise directory
/etc/sv/application/supervise:

file.directory:
- mode: 0755

- user: someuser
- group: someuser
- makedirs: True
- recurse:
- user
- group
- mode
 

# Link the /etc/service/application to kickoff 
# runit to start managing the application
/etc/service/application:
file.symlink:
- target: /etc/sv/application


Reading recent error messages through ps
runsvdir has a useful feature called ‘ps logging’. If any process under its control 

writes anything to its stderr, it appears on runsvdir’s ps entry. So, to have a quick 

glance at what’s currently going on in the stack,


run a command like this: ps -ef | grep runsvdir, and you may see something like this:


 [root@vmtest haproxy]# ps -ef | grep runsvdir
    root      3153     1  0 02:09 ?        00:00:01 runsvdir -P /var/service 
log: aproxy' process is not running?'haproxy' trying to restart?monit: pidfile
 `/var/service/haproxy/supervise/pid' does not contain a valid pidn  umber?monit: 
pidfile `/var/service/haproxy/supervise/pid' does not contain a valid pidnumber?
'haproxy' start:/usr/bin/sv?monit: pidfile `/var/service/haproxy/supervise/pid' 
does not contain a valid pidnumber?'haproxy' process is running with pid 4081?...


Reference:



http://smarden.org/runit/index.html

http://www.sanityinc.com/articles/init-scripts-considered-harmful/

http://rubyworks.rubyforge.org/manual/runit.html