[mythtv-users] 0.19 - local frontend working great , remote frontend not (localhost:6543)

[R. G. Newbury]

Mark Knecht wrote:
> Phil,
>    Thanks. I am sure you are on the right track. However you have
> uncovered a problem here with MySQL permissions that I'm not
> understanding. I hope you can help.


Sounds like you have two concurrent problems going on, both related to 
name resolution and authentication. You need to fix both!

You have 3 machines: 1 backend and 2 frontends.
Edit file /etc/hosts on all three machines and make sure that you have 
your boxen properly identified. Since I own a proper domain, I have used 
a full domain name, but you could just as easily have 'mythbox at my-house'

You need something like:
127.0.0.1       localhost.mandamus.org  localhost 	#Required or things 
break!
192.168.1.98    any1.mandamus.org       any1
192.168.1.97    any2.mandamus.org       any2
192.168.1.96    mythbox.mandamus.org    mythbox
192.168.1.95    thinkpad.mandamus.org       thinkpad
192.168.1.94    any3.mandamus.org       any3
192.168.1.11    netprinter.mandamus.org   netprinter
192.168.1.1     linksys.mandamus.org    linksys    router

Now your machines can resolve each other by name to IP address. Note 
that the last two lines allows me to type http://linksys into firefox 
and get the admin page of my router. Similarly for the netprinter.

The second problem involves the naming of mysql boxes and the people 
allowed to access mysql on the various boxes. This is your other problem.

There are some good pointers deep in the mythtv documentation, as well 
as on the wiki. Even better, there is a good explanation of the manner 
in which mysql authenticates users in the mysql manual (available as pdf 
from mysql)... About Chapter 23... dealing with 'Why can't I sign on? 
Access refused' or somesuch.

To look at your setup, log on to mysql at the backend, as the mysql root 
user. This gives access to the mysql database which 'mythtv' cannot access.
Then 'use mysql' and 'select host, user, password from user;'
This gives the host and user information kept in the user table. You 
will see something like my (very) insecure data:

mysql> select host, user, password from user;
+-------------------+----------+------------------+
| host              | user     | password         |
+-------------------+----------+------------------+
| localhost         | root     |                  |
| tor2.mandamus.org | root     |                  |
| %.mandamus.org    | mythtv   | 0476fc026afffe24 |
| %.mandamus.org    | geoffrey | 330040e53766a829 |
| localhost         | mythtv   | 0476fc026afffe24 |
| localhost         | geoffrey | 330040e53766a829 |
+-------------------+----------+------------------+
6 rows in set (0.00 sec)

This is my office desktop machine setup.
Firstly, I should have a password on 'root'. Secondly, I should probably 
drop the user 'geoffrey' at localhost access as it is a subset of the 
geoffrey@%.mandamus.org' access.

I use this machine as a clone or surrogate for the actual mythbox at 
home. Both are BE/FE setups, but this machine has no tuner cards. The 
database *thinks* it has tuner cards as the database was originally 
copied from the mythbox at a point prior to the first run of 
mythfilldatabase. I keep the versions the same. Both have a user 
'mythtv' which accesses 'localhost' for the backend That way I can run 
mythfilldatabase here and then transfer the progam guide table 
information there without problems. (Tables: credits oldprogram  people 
program programgenres and programrating ONLY).

The line with '%.mandamus.org' is what you want. It will allow user 
mythtv database access from any machine (%) in the domain. If you try 
access from a frontend machine from the mysql command line, you must 
specify the host 'mysql -h backend -u mythtv -pmythtv'

I had problems transferring data if I used the %.mandamus.org setup, as 
the mysqldump program tags its output with the host which produced it, 
so that you cannot (directly at least) restore onto another host.

A table written on any1.mandamus.org is considered NOT to be the same 
table as one on any2.mandamus.org and restoring from file does not work. 
Of course, localhost == localhost. ( I suppose I could edit the 
mysqldump output instead!)

I used the instruction: "grant all on mythconverg to 
'mythtv'@'%.my-house' identified by 'mythtv';"

Try that, and your frontend machines will be differentiated and your 
backend will not be confused. Note that you may need to re-set the 
backend name in mythtv-setup and the IP. As noted in the thread, you 
have been sneaking by, using 'localhost'

Geoff