Comment 1 for bug 1171696

Actually the problem becomes evident earlier on in installation. The first hint is repeated warnings “locale: Cannot set LC_ALL to default locale: No such file or directory.”

Then, while installing postgres, this happens:

«
Setting up postgresql-9.1 (9.1.9-0ubuntu12.04) ...
Error: The locale requested by the environment is invalid.
Error: could not create default cluster. Please create it manually with

  pg_createcluster 9.1 main --start

or a similar command (see 'man pg_createcluster').
»

This wouldn't be so much of a problem if it were merely a matter of setting up the server system badly: just don't do that then. But when you ssh into the server system to install maas, the session picks up your ssh client's locale settings.