[mythtv-users] Questions prior to 0.21 upgrade

[Michael T. Dean]

On 03/11/2008 12:32 PM, Brad DerManouelian wrote:
> On Mar 11, 2008, at 9:21 AM, Derek Stark wrote:
>> I
>> thought I saw something in the release notes about a schema upgrade
>> prompt, but I wasn't sure what that really meant.
>>     
> It's going to warn you that it will upgrade your database instead of  
> just doing it. It will also make a backup for you, but I still  
> recommend making your own backup first. You never know!

I also recommend making your own backup first--and I wrote the code that 
attempts to do a backup automatically.  It's not meant as a replacement 
for user vigilence, but instead as a last-ditch effort to give the user 
options even if they don't properly prepare for the upgrade.

>> 2. Mixing & matching versions
>> If I chicken out on the upgrade and stay on 0.20.2 on my master BE/FE,
>> will I be able to run 0.21 on
>> other FE-only boxes?
>>     
> No. All versions much match. They *must* use the same protocol version  
> which has had many updates since 0,20.

Actually, there are 3 versions that must be identical.

  - MythTV network protocol version
  - MythTV database schema version
  - MythTV library API version (must be identical within a host--i.e. 
mythfrontend and mythbackend and all myth plugins require the same 
library API version)

If either of the first two is incorrect on any host in the system, Myth 
programs will fail to connect.  If the third is "incorrect," it simply 
means you have more than one MythTV version installed on the same 
computer (i.e. a packaged one in /usr and a self-compiled one in 
/usr/local) and you must clean up your system to make it work properly.

Basically, you should /always/ make sure all hosts on your system have 
installed MythTV from the same SVN branch and using the same SVN revision.

Note, also, that mythbackend --version or mythfrontend --version will 
output the network protocol and library API version information as well 
as the SVN branch and revision information.  Please include /all/ the 
version numbers when asking questions or reporting issues or submitting 
tickets.  Stuart M. went to a great deal of trouble to get all that 
information in the --version output to make it easy for people to 
specify exactly what they're running.

Mike