Impossible to cancel bootstrap

Bootstrapping was taking too long (10min+), so I tried to cancel it. It doens't work.

Host is bionic, juju snap is:
juju 2.6.6 8594 stable canonical✓ classic

lxd works just fine on this host.

$ juju bootstrap lxd --keep-broken
Creating Juju controller "localhost-localhost" on lxd/localhost
Looking for packaged Juju agent version 2.6.6 for amd64
To configure your system to better support LXD containers, please see: https://github.com/lxc/lxd/blob/master/doc/production-setup.md
Launching controller instance(s) on localhost/localhost...
 - juju-a83592-0 (arch=amd64)
Installing Juju agent on bootstrap instance
Fetching Juju GUI 2.14.0
Waiting for address
Attempting to connect to 10.0.100.216:22
Connected to 10.0.100.216
Running machine configuration script...
^CInterrupt signalled: waiting for bootstrap to exit
Bootstrap agent now started
Contacting Juju controller at 10.0.100.216 to verify accessibility...
^CInterrupt signalled: waiting for bootstrap to exit
^CInterrupt signalled: waiting for bootstrap to exit
^CInterrupt signalled: waiting for bootstrap to exit
^CInterrupt signalled: waiting for bootstrap to exit
^CInterrupt signalled: waiting for bootstrap to exit
^CInterrupt signalled: waiting for bootstrap to exit
^CInterrupt signalled: waiting for bootstrap to exit
^CInterrupt signalled: waiting for bootstrap to exit
^CInterrupt signalled: waiting for bootstrap to exit
^CInterrupt signalled: waiting for bootstrap to exit
^CInterrupt signalled: waiting for bootstrap to exit
^CInterrupt signalled: waiting for bootstrap to exit
^CInterrupt signalled: waiting for bootstrap to exit
^CInterrupt signalled: waiting for bootstrap to exit
^CInterrupt signalled: waiting for bootstrap to exit
^CInterrupt signalled: waiting for bootstrap to exit
^CInterrupt signalled: waiting for bootstrap to exit
^CInterrupt signalled: waiting for bootstrap to exit
^CInterrupt signalled: waiting for bootstrap to exit
^CInterrupt signalled: waiting for bootstrap to exit
^CInterrupt signalled: waiting for bootstrap to exit
^CInterrupt signalled: waiting for bootstrap to exit
^CInterrupt signalled: waiting for bootstrap to exit
^CInterrupt signalled: waiting for bootstrap to exit
^CInterrupt signalled: waiting for bootstrap to exit
^CInterrupt signalled: waiting for bootstrap to exit
^CInterrupt signalled: waiting for bootstrap to exit
^CInterrupt signalled: waiting for bootstrap to exit
^CInterrupt signalled: waiting for bootstrap to exit
^CInterrupt signalled: waiting for bootstrap to exit
^CInterrupt signalled: waiting for bootstrap to exit
^CInterrupt signalled: waiting for bootstrap to exit
^CInterrupt signalled: waiting for bootstrap to exit
^CInterrupt signalled: waiting for bootstrap to exit
^CInterrupt signalled: waiting for bootstrap to exit
^CInterrupt signalled: waiting for bootstrap to exit
^CInterrupt signalled: waiting for bootstrap to exit
^CInterrupt signalled: waiting for bootstrap to exit
^CInterrupt signalled: waiting for bootstrap to exit
^CInterrupt signalled: waiting for bootstrap to exit
^CInterrupt signalled: waiting for bootstrap to exit
^CInterrupt signalled: waiting for bootstrap to exit
^CInterrupt signalled: waiting for bootstrap to exit
^CInterrupt signalled: waiting for bootstrap to exit
^CInterrupt signalled: waiting for bootstrap to exit
^CInterrupt signalled: waiting for bootstrap to exit
^CInterrupt signalled: waiting for bootstrap to exit
^CInterrupt signalled: waiting for bootstrap to exit
^CInterrupt signalled: waiting for bootstrap to exit
^CInterrupt signalled: waiting for bootstrap to exit
^CInterrupt signalled: waiting for bootstrap to exit
^CInterrupt signalled: waiting for bootstrap to exit
^CInterrupt signalled: waiting for bootstrap to exit
^CInterrupt signalled: waiting for bootstrap to exit
^CInterrupt signalled: waiting for bootstrap to exit
^CInterrupt signalled: waiting for bootstrap to exit
^CInterrupt signalled: waiting for bootstrap to exit
^CInterrupt signalled: waiting for bootstrap to exit