ahadshafiq

Zero downtime deploys with unicorn + nginx + runit + rvm + chef

Below are the actual files we use in one of our latest production applications at Agora Games to achieve zero downtime deploys with unicorn. You've probably already read the GitHub blog post on Unicorn and would like to try zero downtime deploys for your application. I hope these files and notes help. I am happy to update these files or these notes if there are comments/questions. YMMV (of course).

Other application notes:

• Our application uses MongoDB, so we don't have database migrations to worry about as with MySQL or postgresql. That does not mean that we won't have to worry about issues with the database with indexes being built in MongoDB or what have you.
• We use capistrano for deployment.

Salient points for each file:

ahadshafiq

#create & deploy lamp droplet

#login via ssh as root

#initial setup (ref: http://library.linode.com/getting-started#sph_logging-in-for-the-first-time)

# update /etc/hosts (to "thalassophobia.surrealroad.com")

nano /etc/hosts
  #

ahadshafiq

Instead of 
        rails server
do:
        rails s -d

then to kill it, find which process is using the port:
        lsof -i :3000

finally, kill the process:
        kill -9 $(lsof -i :3000 -t)

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ListAllCommands | grep searchstr
function ListAllCommands
{
    COMMANDS=`echo -n $PATH | xargs -d : -I {} find {} -maxdepth 1 \
        -executable -type f -printf '%P\n'`
    ALIASES=`alias | cut -d '=' -f 1`
    echo "$COMMANDS"$'\n'"$ALIASES" | sort -u
}

ahadshafiq

http://nvie.com/posts/a-successful-git-branching-model/
Master
      Develop
            Feature1
            Feature2
            Feature3

Get original source updates to master. By git pull origin originalmaster.
Check where git remote is for originamaster. git remote -v

ahadshafiq

db:create creates the database for the current env
db:create:all creates the databases for all envs
db:drop drops the database for the current env
db:drop:all drops the databases for all envs
db:migrate runs migrations for the current env that have not run yet
db:migrate:up runs one specific migration
db:migrate:down rolls back one specific migration
db:migrate:status shows current migration status
db:migrate:rollback rolls back the last migration
db:forward advances the current schema version to the next one

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put <%= params.inspect %> in application.html.erb

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http://mislav.uniqpath.com/2010/07/git-tips/

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rvm -v
rvm get head
rvm -v

rvm osx-ssl-certs status all
The above will show if certificates are outdated:
Certificates for /opt/sm/pkg/versions/openssl/1.0.1c/ssl/cert.pem: Old.

rvm osx-ssl-certs update all
The above will update the certificates:

ahadshafiq

                                             
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Server Stack
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As with other *nix applications, you can control nginx through the use
of signals. To use signals, you’ll need the process ID.
nginx is architected as a single master
process with any number of worker processes.

You can stop the master process with the