[chef] Re: Dependency between nodes

[Ted B < >]

> On Sun, May 17, 2015 at 11:16 PM, Vikas Roonwal 
> <
 >
>  wrote:
> Hi,
> I wanted to know if chef is suitable for the following scenari, if yes then 
> what would be the best way to achieve it.
> We need to deploy a web-application which contains 3 components
> 1. A WAR file - portal
> 2. An application - A module which interacts with the portal for different 
> tasks
> 3. DB 
> 4. Active MQ - To facilitate the communication b/w Portal and App
> 
> If the above 4 components are on different machines/nodes, can the 
> deployment be made atomic i.e. either all nodes get upgraded or none does.
> I have an ANT script which can handle the deploy-all or none on a sinle 
> node, is chef a possible solution if we need to suppprt the same across 
> nodes?
> 
> Thanks,
> ~Vikas

As mentioned by niristotle; you can use chef to build the infrastructure and 
deploy the app.

I’ve used chef to build up from a base image a Tomcat server, then configure 
tomcat, then deploy a WAR file from a known location into that server. I then 
image that resulting server to be used for an Amazon Auto Scaling group. 
However; Chef is not necessarily needed here as I’m using it purely as a 
build chain. You could do this with packer, or a number of other tools.

If you wanted to continue to maintain state on this server once built; chef 
would have that added benefit.

In my case I simply have a role as shown which is used to apply to a node 
bootstrapped with knife (in AWS in my case):

{
  "name": "java-appserver",
  "default_attributes": {},
  "override_attributes": {
    "java": {
      "jdk_version": "7"
    },
    "oracle": {
      "accept_oracle_download_terms": true
    },
    "aws": {
      "s3": {
        "bucket": "myappdeploybucket"
      }
    },
    "tomcat": {
      "java_options": "${JAVA_OPTS} -Djava.awt.headless=true 
-Dfile.encoding=UTF-8 -server -Xms512m -Xmx25g -XX:NewSize=256m 
-XX:MaxNewSize=256m -XX:PermSize=256m -XX:MaxPermSize=1g 
-XX:+DisableExplicitGC -XX:+CMSClassUnloadingEnabled"
    }
  },
  "json_class": "Chef::Role",
  "description": "Role for Java Apps Servers using OpenJDK7",
  "chef_type": "role",
  "run_list": [
    "recipe[java]",
    "recipe[tomcat]",
    "recipe[tomcat::users]",
    "recipe[simianarmy::app-deploy-edda]"
  ]
}

I’m using community java and tomcat cookbooks to setup the Web App Server.
https://supermarket.chef.io/cookbooks/java
https://supermarket.chef.io/cookbooks/tomcat

The final recipe merely drops the WAR into the tomcat webs directory to 
auto-deploy

# Copy EDDA WAR to webapps for autodeployment - Requires that instance have 
role with access to bucket
execute "aws s3 cp #{node['simianarmy']['urls']['edda']} 
/var/lib/tomcat7/webapps/" do
  action :run
  not_if { 
File.exist?("/var/lib/tomcat7/webapps/#{server_file(node['simianarmy']['urls']['edda'])}")
 }
end

-- 
Ted
GPG Key: 0x2B272DFD | E564 BCC1 F601 5D1F 01CD AC10 C37D D2B0 2B27 2DFD