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I've installed MAAS to get a set of Ubuntu 12.04 servers running and I used juju to install the hadoop charm on them, but I needed to change some of the configuration settings on one of the machines to make it work. I noticed that after rebooting the machine my changes were removed and the original settings were back.

Is there a non-hacky way (custom shell script that runs on reboot) to define configurations that need to be reloaded? In my case I would like to simply define the file that should be reloaded on reboot. I believe this is an issue that goes beyond the hadoop charm specifically (hopefully).


  • 12.04 Stock MAAS
  • 12.04 Stock juju (0.5bzr)
  • 12.04 Stock Hadoop charm (but my question is for the general case)
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up vote 0 down vote accepted

The system config will happen in two places: in the commissioning phase, when the 'OS is installed', and in the charms that get deployed, when configuration can happen.

If the config your want is at the OS / hardware setup level, then look into commissioning scripts. If it's more related to the workload, look into a subordinate charm that you can deploy onto any machine to get the result you want.

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Thanks. Those are good starting point to look at. I will accept the answer even though I haven't really solved my problem yet - I think my original problem was too specific. Thanks again. – William Jun 4 '13 at 20:34

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