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

[Bill Meek]

> On 11/22/20 5:20 PM, Bill Meek wrote:
>> On 11/22/20 6:23 PM, Mike Carron wrote:
>>> My backend host recently failed badly enough that I was not able to
>>> salvage anything so I replaced the hardware and installed a new Ubuntu
>>> 20.04 and a new v31 mythtv-backend-master with xmltv.
>>>
>>> I then upgraded a remote frontend (Ubuntu 18.04) from MythTV 30 to 31
>>> but that frontend will not connect to the database.
>>>
>>> I've checked and rechecked the frontend setup screen and everything is
>>> correct. The config.xml files for both look like they should work. I've
>>> tried the backend config with </host> = localhost and = 192.168.0.222
>>> (the backend machine IP). The frontend config host is 192.168.0.222.
>>>
>>> I know the ip addresses are good. I can load 192.168.0.222:6544 into the
>>> address line of the Firefox on the frontend machine and it finds the
>>> database immediately.
>>>
>>> I'm no doubt missing something obvious but I can't find it. It seems
>>> like I have worn out 2 search engines trying.
>>>
>>> Suggestions?
>>>
>>> mike
>> On the backend's config.xml, always use localhost (or 127.0.0.1 if localhost
>> can't be resolved). That causes a socket to be used.
>>
>> See if mysql is running on the backend: systemctl status mysql mysqld mariadb
>> Probably is if the backend is running OK.
>>
>> One of the above ^^^ should be running. All three will work if
>> using mariadb and the Alias= lines in the service are setup.
>>
>> On the frontend, the following three must work: ping 192.168.0.222,
>> nmap --reason -p 3306 192.168.0.222 (expect a syn-ack) and then:
>>
>>    mysql --host=192.168.0.222 --user=mythtv --password=<from config.xml> mythconverg

On 11/22/20 8:50 PM, Mike Carron wrote:
> backend's config.xml uses localhost.
> 
> status for mysql, mysqld and mariadb: active (running)
> 
> ping 192.168.0.222 works
> 
> nmap --reason -p 3306 192.168.0.222 produces:
> 
> PORT     STATE  SERVICE REASON
> 3306/tcp closed mysql   reset ttl 64
> MAC Address: A8:5E:45:E3:5A:9F (Unknown)
> 
> mysql --host=192.168.0.222 --user=mythtv --password=<from config.xml>
> mythconverg produces:
> 
> ERROR 2003 (HY000): Can't connect to MySQL server on '192.168.0.222' (111)
> 
> This looks like the problem but I have no idea how to fix it.

See the answer from Ramesh.

grep --recursive bind.address /etc/mysql

My choice, which allows connections from any host
including IPv6:

$ cat /etc/mysql/mariadb.conf.d/mythtv.cnf
[mysqld]
bind_address=::

Restart mysql for it to take affect.

-- 
Bill