On Mon, Feb 15, 2016 at 6:29 PM, Bruce Momjian <bruce@momjian.us> wrote:
Someone on IRC reported that if they had run the pg_upgrade-created delete_old_cluster.sh shell script it would have deleted their old _and_ new data directories. (Fortunately they didn't run it.)
I was confused how this could have happened, and the user explained that their old cluster was in /u/pgsql/data, and that they wanted to switch to a per-major-version directory naming schema, so they put the new data directory in /u/pgsql/data/9.5. (They could have just moved the directory while the server was down, but didn't.)
Unfortunately, there is no check for having the new cluster data directory inside the old data directory, only a check for tablespace directories in the old cluster. (I never anticipated someone would do this.)
Interesting - I definitely wouldn't have expected that either. And it definitely seems like a foot-gun we should protect the users against.