Technotes for future me


Finding Hosts

mco ping
mco ping -W "/some match pattern/"
mco ping -S "<some select query>"

mco find                                 # List all hosts known

Finding Groups of Hosts

Simple facts can be matched with -F

mco find -F ipaddress=
mco find -F kernel_version=/3.4/ -F fqdn=/db/

Structured facts (introduced with facter 2) can only be matched with -S like this

mco find -S 'fact("").value='
mco find -S 'fact("os.distro.codename").value=jessie'

Fact Histograms

To get the distribution of all fact values:

mco facts timezone

Plugin Commands

# List agents, queries, plugins...
mco plugin doc
mco plugin doc <name>

# Puppet runs
mco puppetd status
mco puppetd status -I <host>
mco puppetd runonce -I <host>
mco puppetd <enable|disable> -I <host>

mco rpc puppetd status -F <fact>=<value>
mco rpc puppetd runonce -F <fact>=<value>
mco rpc puppetd runonce -W /pattern/

mco rpc service start service=httpd
mco rpc service stop service=httpd

mco facts <keyword>
mco inventory --lco     # List collectives
mco inventory <node name>
mco rpc rpcutil inventory -I <node name>
mco rpc rpcutil get_fact fact=<fact name>

Remote Command Execution

With Puppet RAL

mco rpc puppetral -F <filter> create type=exec title="/bin/bash -c 'echo Hallo'"
mco rpc puppetral --batch 5 --batch-sleep 10 create type=package title="htop"

(Note: when using RAL do not combine –limit with –batch as –batch would be ignored!)

With shell plugin installed

mco shell run <command>
mco shell run --tail <command>

mco shell start <command>    # Returns an id
mco shell watch <id>
mco shell kill <id>
mco shell list

Formatted Reports

Formatting can be achieved using inventory scripts. General syntax:

mco inventory [<some filter>] --script <mco script>


mco inventory -F fqdn=/db/ --script <(echo "
inventory do
  format '%s %s'
  fields { [ identity, facts['operatingsystemrelease'] ] }

Ansible like Playbooks

YAML playbooks can be done with Choria.

Last updated on 31 Jan 2021
Published on 25 Dec 2019
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