I have two Linux servers that are pretty similar to each other, and both are running PostgreSQL servers, but in one server a certain Perl script succeeds in connecting to the localhost server whereas in the other one the same script fails. The error on the second server is of the form "fe_sendauth: no password supplied". I have verified all the possible reasons that I can think of for why this script succeeds on one server but fails on the other. In all these respects the two set ups are absolutely identical: same pg_hba.conf files, same script parameters, same versions of Postgres, same everything.
I have run out of ideas! How can I troubleshoot this further? Is there some way to have Postgres dump excruciatingly thorough details about every single step of the authentication sequence? Any other suggestions would be greatly appreciated. Thanks! k