dashboard and external database - can't connect

[remi.du...@gmail.com]

Hello,

This is my current setup (everything is on CentOS 7 and I use Archivematica 1.5.1-1):
- one machine with dashboard + processing (MCP)
- one machine with storage
- one machine for MySQL databases

I want the dashboard to put its MySQL database on the database machine. To do so, I create and MCP database on the remote machine with the correct persmissions.
As stated here: https://www.archivematica.org/en/docs/archivematica-1.5/admin-manual/maintenance/security/#mysql
I change the following files:
- /etc/archivematica/archivematicaCommon/dbsettings
- /usr/share/archivematica/dashboard/settings/common.py (here I'm a bit surprized the PORT is not taken from the config as the others)

I also changed the files /etc/sysconfig/archivematica*

I have a strange behavior:
- when I run "/usr/lib/python2.7/archivematica/dashboard/bin/python manage.py syncdb --noinput", the database is correctly updated remotely
- when I connect to the dashboard, I have the error (on the upper right corner) "Error trying to connect to database. Trying again..."
- the service MCPServer doesn't want to start because it can't connect to the database (even if the host it tries to connect is OK)

If I install the database locally, everything is fine...

Do you know how to setup a database remotely? and how I can have logs on this error? I can't find any logs telling me the credentials + host + port used to connect to the database...

Moreover, I I do the following steps, I'm able to get information from tha database (as an archivematica user):
$ cd /usr/share/archivematica/dashboard/
$ source /usr/lib/python2.7/archivematica/dashboard/bin/activate
$ python manage.py shell
>>> from main.models import WatchedDirectory
>>> len(WatchedDirectory.objects.values())
24

Thus, I can't understand what the problem can be...