rackspace cloud-config requested changes

[Scott Moser]

Below is the /etc/cloud/cloud.cfg.d/99-rackspace-general.cfg I found in
an onmetal instance with serial 20180405.

A list of changes that I think should be made:
 a.) manage_resolv_conf: This does not do anything on ubuntu. the 'resolv_conf' module that would apply those changes does not run on Ubuntu. Suggestion is to just drop that.

 b.) ssh_deletekeys: Setting this to 'false' is probably a bad idea. It means if the keys already existed they wont be regenerated. If you don't know why that is there, then you should absolutely remove it. Any image with key files in place (such as a captured image) will have known/static host keys.

 c.) resize_rootfs: noblock. Just drop this. On the instance I launched, resizing of the root filesystem took .230 seconds. That was part of a 2 minute and 29 second boot. Not worth the complication. Basically any kernel newer than precise resizes magic fast.

 d.) datasource_list: on Bionic, please drop this. It is not necessary as ds-identify will correctly identify ConfigDrive based on the filesystem label 'config-2'. There is no performance benefit to setting it, and doing so breaks 'dpkg-reconfigure cloud-init'.

e.) renderers: On Bionic, please remove this. cloud-init will select the correct renderer unless the user installed ifupdown. If the user installed ifupdown, that is assumed to be what they wanted.

| datasource_list: [ ConfigDrive, None ]
| manage_resolv_conf: true
| manage_etc_hosts: localhost
| chpasswd: {expire: false}
| disable_root: false
| user: root
| ssh_pwauth: false
| ssh_deletekeys: false
| resize_rootfs: noblock
|
| system_info:
| network:
| renderers: [ 'netplan' ]
| package_mirrors:
| - arches: [i386, amd64]
| failsafe:
| primary: http://archive.ubuntu.com/ubuntu
| security: http://security.ubuntu.com/ubuntu
| search:
| primary:
| - http://rackspace.clouds.archive.ubuntu.com/ubuntu/
| security: []
| - arches: [default]
| failsafe:
| primary: http://ports.ubuntu.com/ubuntu-ports
| security: http://ports.ubuntu.com/ubuntu-ports
|