GOV.UK
Remove a machine
Before you start, make sure that the machines you are removing are no longer needed for anything.
1. Remove the node from the puppetmaster
You need to remove the nodes from the puppetmaster in each environment. This is needed to clean up exported resources from Puppet, including removing checks from Icinga.
First, disable Puppet on the machines you wish to remove.
Next, SSH into the puppetmaster for the environment:
$ ssh puppetmaster-1.management.production
for Carrenza, or
$ govukcli set-context integration
$ govukcli ssh puppetmaster
for AWS.
Then run this on each machine:
$ govuk_node_clean <machine_name>
Where <machine_name> might be machine-name-1.vdc-name.production (Carrenza)
or ip-a-b-c-d.eu-west-1.compute.internal (AWS).
To find the names of the machines, you can list the nodes on puppetmaster:
$ sudo puppet cert list --all
If govuk_node_clean was successful, you will get output like:
Submitted 'deactivate node' for redirector-1.redirector.production with UUID 0fb445ff-d660-41eb-b6d2-eca40447d4bf
Notice: Revoked certificate with serial 127
Notice: Removing file Puppet::SSL::Certificate redirector-1.redirector.production at '/etc/puppet/ssl/ca/signed/redirector-1.redirector.production.pem'
After this, Icinga will forget about the machine when it next runs Puppet. You can force this with:
$ ssh monitoring-1.management.production
$ govuk_puppet --test
You may need to wait a few minutes, but it should then disappear from the “Host Detail” page in Icinga.
2. Remove from puppet
If you are removing a class of machines, you will need to remove the definitions from Puppet.
Carrenza
3. Remove from vCloud Director
Sign in to the vCloud Director instance for the given environment. Go to ‘My Cloud’, search for the given machine, stop it, and then delete it.
4. Remove from govuk-provisioning
If your machine class matches a vDC, be careful not to remove firewall rules that apply to the vDC.
AWS
3. Remove from Terraform
If you’re removing a class of machines, first deploy Terraform
for the relevant project using the destroy action. This will remove all the
EC2 instances.
Then, remove the project itself from govuk-aws.
If you’re removing a single machine, change the asg_size for the relevant
project in govuk-aws-data (example) and
deploy Terraform.