Running commands from Puppet Ent. master using MCollective.

Puppet doesn't support running commands by default remotely using the PE MCollective.

This needs us to do come changes in the puppet config and also to create a shell script to test those changes from puppet master.

Actually for this to work, we need to change the config on the mcollective server running on puppet agent nodes.

Since edits in server.cfg are not allowed or supported by Puppet, we need to utilize /etc/puppetlabs/mcollective/plugin.d folder.

Using puppet documentation from: https://docs.puppet.com/mcollective/configure/server.html#plugin-config-directory-optional

We need to create a file names puppet.cfg (we use an mcollective puppet plugin properites) as seen below:

[root@vardamir ~]$ cat /etc/puppetlabs/mcollective/plugin.d/puppet.cfg

resource_allow_managed_resources = true

resource_type_whitelist = exec

[root@vardamir~]$

This will allow the mco command to use the exec resource, any other resource that needs to be enables needs to be comma separatly listed in the same manner.

Once this change is done on the node running puppet agent we need to restart the pe-mcollecive service on that node.

A good approach is to handle this as a puppet module, to manage the puppet.cfg and to notify the pe-mcollecive service if the file changes.

To start using command from Puppet master, login to the puppet user peadmin we run like this:

mco puppet resource exec tc_restart command="/bin/bash -c \"cd /apps/vfabric-tc-server/vfabric-tc-server-standard-2.9.2.RELEASE/my_tc/bin;./tcruntime-ctl.sh restart\"" -I  beren.mysite.com

From a script it will need further escaping as we need to run from root or sudo and then use su  - peadmin -c " . . "

Combine this with Jenkins or Rundeck and you can control any node and execute any thing remotely without using SSH.