[ubuntu-cloud] RFC: server-lucid-ec2-config: user-data configuration file

Eric Hammond ehammond at thinksome.com
Mon Dec 21 18:46:23 GMT 2009


Regarding this snippet in the sample config file:

  # Update apt database on first boot
  # (ie run apt-get update)
  # Default: true
  apt_update: false

I am concerned about the implication that apt-get update might be run
automatically on first boot even when the old style user-data script is
provided or when users are configuring through automated ssh on startup.

I understand and support the desire to make things easy for new users,
but would suggest that it is also important to let advanced users
configure their new instances quickly and not get in their way.

Here's a sample scenario:

  user-data script changes apt sources to a different repository,
  includes multiverse, and/or adds a PPA.  user-data script then
  runs apt-get update itself and starts installing software.

If apt-get update is run automatically before this starts, then the
user-data script has to figure out how to wait for the (useless) update
to complete, making the code more complex and delaying the startup of
the instance.  This also places a startup dependency on the existing apt
mirrors which I sometimes do not wish to have in my instances.

If the apt-get update were to default to false, then the new config file
approach can easily switch it to true, not breaking the way that it
currently works.

Eric Hammond

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