Dovecot/MSQL issue

[John Fawcett]

On 30/06/2019 13:36, Aki Tuomi via dovecot wrote:
>>
>> Hello, I'm trying to work through an issue that cropped up on a server I've been working on and haven't found a very good workaround.
>>
>> Dovecot is operating in a jailed environment.
>>
>> The configuration in dovecot-sql.conf.ext has been set appropriately with the host=127.0.0.1 (which works from a jailed environment) and when dovecot attempts to auth it appears to perform a reverse dns lookup and overwrites the host with the result localhost before using the msql credentials 'user'@'localhost' which then fails after timing out. 
>>
>> I'm currently running version 2.2.33.2 of dovecot.
>>
>> The workaround seems to be to have two credentials for the same user. 
>> 'user@'localhost' and 'user'@'127.0.0.1'; 
>> postfix operates in a jail as well and works around the jail issue in the same way but doesn't overwrite the specified host with a reverse dns lookup.
>>
>> Anyone have any suggestions on how to handle this issue better? or maybe there's a way to force different behavior which I haven't yet found in the documentation?
>>
>> Any help is much appreciated.
>>
>> Best Regards.
> Hi!
>
> The 127.0.0.1 issue is actually a MySQL issue, unfortunately. 
>
> " On Unix, MySQL programs treat the host name localhost specially, in a way that is likely different from what you expect compared to other network-based programs: the client connects using a Unix socket file. The --socket option or the MYSQL_UNIX_PORT environment variable may be used to specify the socket name. "
>
> So not really something we could do much about.
>
> Aki

Aki

it is possible to force the use of tcp socket instead of unix socket by
specifying an ip instead of the hostname localhost. As I understood it
Nathan is specifying 127.0.0.1 so that will connect with tcp socket.

John