clean: add param to remove /etc/machine-id for golden image creation

Typically when a cloud-image boots /etc/machine-id should be
auto-generated if /etc/machine-id does not exist. Some cloud images
appropriately generate /etc/machine-id if the image is recognized
as a clone, in most other cases it is a best practice to remove
/etc/machine-id and let DBUS or systemd do the work of generating
a new UUID on next boot so the cloned VMs are represented
uniquely to any monitoring/management software.

1 files changed, 13 insertions, 0 deletions

diff --git a/cloudinit/cmd/clean.py b/cloudinit/cmd/clean.py
index 0d7ca15a..65d3eece 100755
--- a/cloudinit/cmd/clean.py
+++ b/cloudinit/cmd/clean.py
@@ -22,6 +22,8 @@ from cloudinit.util import (
     is_link,
 )
 
+ETC_MACHINE_ID = "/etc/machine-id"
+
 
 def get_parser(parser=None):
     """Build or extend an arg parser for clean utility.
@@ -49,6 +51,15 @@ def get_parser(parser=None):
         help="Remove cloud-init logs.",
     )
     parser.add_argument(
+        "--machine-id",
+        action="store_true",
+        default=False,
+        help=(
+            "Remove /etc/machine-id for golden image creation."
+            " Next boot generates a new machine-id."
+        ),
+    )
+    parser.add_argument(
         "-r",
         "--reboot",
         action="store_true",
@@ -108,6 +119,8 @@ def remove_artifacts(remove_logs, remove_seed=False):
 def handle_clean_args(name, args):
     """Handle calls to 'cloud-init clean' as a subcommand."""
     exit_code = remove_artifacts(args.remove_logs, args.remove_seed)
+    if args.machine_id:
+        del_file(ETC_MACHINE_ID)
     if exit_code == 0 and args.reboot:
         cmd = ["shutdown", "-r", "now"]
         try: