heya--
Been playing with dovecot today as I was learning about the features I haven't used yet like the director/proxy stuff.
I setup a basic dovecot stack today which is 1 director and 1 IMAP dovecot server behind it.
I have one user setup in MySQL and when I first changed from proxy mode to director mode I left the host column populated with the IMAP server. Once I confirmed this was working I then changed host to "" not NULL.
When I then preformed my next check I got these errors(no details omitted as this is a test system):
Feb 20 14:57:19 smtp-test dovecot: auth-worker(15423): Debug: sql(email3@example.com,10.107.0.8): query: SELECT email as user, password, host, 'Y' AS proxy_maybe, 'user' AS master, 'password' AS pass, 'any-cert' AS 'ssl' FROM virtual_users WHERE email='email3@example.com'; Feb 20 14:57:19 smtp-test dovecot: auth: Error: proxy(email3@example.com,10.107.0.8,<Zz0b430PigAKawAI>): DNS lookup for failed: Invalid input from dns-client Feb 20 14:57:19 smtp-test dovecot: auth: Error: close((null)) failed: Bad file descriptor
When I changed the host data from "" to NULL all worked as expected.
So the question is: is this a bug with the error output? It was kind of hard for me to diagnose at first without leaning on support in the freenode channel.
This is very repeatable as it is a proper error, you can't resolve "".
--julian