[mythtv-users] mythfrontend can't connect to backend/database

[starcycle]

On Mon, Apr 21, 2008 at 6:29 AM, Mike Perkins
<mikep at randomtraveller.org.uk> wrote:
> starcycle wrote:
>  >
>  > ====================================
>  > 2008-04-12 19:59:14.972 Using runtime prefix = /usr, libdir = /usr/lib
>  > 2008-04-12 19:59:15.052 Empty LocalHostName.
>  > 2008-04-12 19:59:15.265 Using localhost value of moe
>  > 2008-04-12 19:59:15.403 New DB connection, total: 1
>  > 2008-04-12 19:59:15.454 Connected to database 'mythconverg' at host: localhost
>  > 2008-04-12 19:59:15.466 Closing DB connection named 'DBManager0'
>  > 2008-04-12 19:59:15.469 Connected to database 'mythconverg' at host: localhost
>  > 2008-04-12 19:59:15.524 New DB connection, total: 2
>  > 2008-04-12 19:59:15.526 Connected to database 'mythconverg' at host: localhost
>  > 2008-04-12 19:59:15.538 Current Schema Version:
>  > 2008-04-12 19:59:15.540 DataDirectProcessor::FixProgramIDs() -- begin
>  > 2008-04-12 19:59:15.543 New DB DataDirect connection
>  > 2008-04-12 19:59:15.546 Connected to database 'mythconverg' at host: localhost
>  > 2008-04-12 19:59:15.597 DB Error (Fixing program ids in recorded):
>
>  ...amongst other things. If you look at the snippet above, this indicates that
>  you have not set the ip address for mythbackend *in the back end machine*. What
>  is shown above is the default 'localhost'. If this value is not set correctly,
>  it's not surprising you are getting connection problems from other machines.
>

The point is, everything was set up correctly on both backend and all
the frontends. The database was only refusing connection at the level
of tcp wrappers. This seems to be a security feature in debian,
probably turned off or pre-configured in the myth-specific distros:

/usr/share/doc/mysql-server-5.0/README.Debian:

'For security reasons, the Debian package has enabled networking only on the
loop-back device using "bind-address" in /etc/mysql/my.cnf. Check with
"netstat -tlnp" where it is listening. If your connection is aborted
immediately see if "mysqld: all" or similar is in /etc/hosts.allow and read
hosts_access(5).'

so if anyone is ever having problems connecting to a debian backend,
make sure to check the host access files, and add mysqld : <lan IPs>
(or whatever) to allow access.

regards