[mythtv-users] Ver 31 frontend cannot connect to the database

[Mike Carron]

On 11/24/20 10:12 AM, Bill Meek wrote:
> On 11/24/20 10:22 AM, Mike Carron wrote:
>> On 11/24/20 3:07 AM, Stephen Worthington wrote:
>>> On Mon, 23 Nov 2020 19:37:37 -0800, you wrote:
>>>
>>>> On 11/23/20 6:09 PM, Stephen Worthington wrote:
>>>>> On Mon, 23 Nov 2020 16:57:05 -0800, you wrote:
>>>>>
>>>>>> On 11/23/20 7:13 AM, Bill Meek wrote:
>>>>>>
>>>>>>       |
>>>>>>
>>>>>>       snip
>>>>>>
>>>>>>       |
>>>>>>
>>>>>>       At least my /etc/mysql/mariadb.conf.d/50-server.cnf, appears to
>>>>>>       be one that would be released by a package manager and changes to
>>>>>>       it could be overwritten by updates/upgrades.
>>>>>>
>>>>>>       I'd move the mythtv.cnf file to /etc/mysql/mariadb.conf.d to
>>>>>>       prevent future surprises.
>>>>>>
>>>>>> I've gone over everything and I have to conclude that port 3306 on the
>>>>>> backend being closed is the culprit. Since mythfrontend wants to use
>>>>>> port 3306 to communicate with the backend I'm not going to get anywhere
>>>>>> until port 3306 is opened. Unfortunately I do not know how to do that.
>>>>>>
>>>>>> How do I open port 3306?
>>>>>>
>>>>>> mike
>>>>> As I said, fix the MariaDB bind-address.  Port 3306 is the port for
>>>>> MariaDB, not MythTV.  MariaDB is still binding to 3306 only on
>>>>> localhost.  It needs to bind 3306 on all IP addresses.
>>>> ma
>>>> How do I do that?/
>>>>
>>>> mike
>>> As per my previous post:
>>>
>>> In your MariaDB settings, the "bind-address=127.0.0.1" is the one
>>> being used by MariaDB, instead of the "bind-address=::", because of
>>> the order it reads the config files.  The last one read is the one
>>> that gets used.  So the simple thing to do is just to comment out the
>>> "bind-address=127.0.0.1" line in the
>>> /etc/mysql/mariadb.conf.d/50-server.cnf file by putting a # at the
>>> start of the line.  Then restart MariaDB:
>>>
>>> sudo systemctl restart mariadb
>>> _______________________________________________
>> Did that already.
>>
>> I did some more checking and found that "port = 3306" was commented out
>> in /etc/mysql/mariadb.conf.d/50-server.cnf. I uncommented it and now I
>> no longer see the "ERROR 2002 (HY000): Can't connect to MySQL server on
>> '192.168.0.222' (115)" message.
> Hard to argue with success, But, the default MySQL/MariaDB  port *is* 3306.
> https://mariadb.com/kb/en/connecting-to-mariadb/
>
> I just commented out the one and only active port= line and restarted the
> server. It works fine.
>
> This will display the port in use:
>
> SHOW GLOBAL VARIABLES LIKE 'port';
> +---------------+-------+
> | Variable_name | Value |
> +---------------+-------+
> | port          | 3306  |
> +---------------+-------+
> 1 row in set (0.002 sec)
>
> The same is true for SESSION VARIABLES.
>
> I'd re-comment the line you changed and restart the SQL server.
>
> If it truly does work, then the change shouldn't be made in a
> .cnf file that will be overwritten by a package manager. That
> could happen at any time, for example 2 years from now when
> you upgrade to a new distribution. And will have forgotten
> about the change. Changes like this should go in the same
> place the bind-address was changed. Just before or after it
> would be OK.
>
> But: your computer, your choice.
>

When I leave port = 3306 commented out, the remote frontend errors out
with "Cant find the database."

When I removed the comment, the remote frontend connected to the
database immediately. Now I guess it's time to double check the
backend-setup and make sure no surprises surfaced there.

I built a file with bind-address and port variables and stored it in
/etc/mysql/conf.d. Hopefully it will be safe there.

mike