[mythtv-users] migrating a backend

[Michael T. Dean]

On 03/11/2009 09:57 PM, Nick Rout wrote:
> On Thu, Mar 12, 2009 at 2:55 PM, Nick Rout wrote:
>   
>> On Thu, Mar 12, 2009 at 2:51 PM, Jason Weida wrote:
>>     
>>> I've done some googling, wiki-searching and a gossamer search and have not
>>> typed in the magic words that would point me to a good set of instructions
>>> on what needs to be done in order to migrate to a new backend.  Well, really
>>> not so much new.  I'm planning on wiping my current ubuntu based backend
>>> (where Myth was added as an afterthought) and installing mythbuntu on the
>>> same machine.  I've got my OS/DB on a 40G drive, my recordings on a 160G
>>> drive.  I'm also adding a new 250G drive for additional storage space.
>>>
>>> I've found and downloaded mythconverg_backup.pl and mythconverg_restore.pl
>>> and feel comfortable running those, but without some solid reassurance, I
>>> don't yet have the guts to pull the trigger on this migration.  I'd
>>> obviously like to retain all my recordings, commercial scans, recording
>>> schedules and recording history, which I assume is all covered in the
>>> database backup, sans the recordings which will remain on the same 160G
>>> drive.  The rest is easy enough to set up (installing my HDHR, SchedDirect
>>> info).
>>>
>>> So, here's my plan:
>>> 1. backup the database using the mythconverg_backup script and copy to a
>>> flash drive.
>>> 2. pop in the mythbuntu live CD, run through the guided installation, taking
>>> care not to format my 160G drive.
>>> 3. restore the database using the mythconverg_restore.pl script
>>> 4. run through the mythbackend setup GUI to set up my tuner
>>>
>>> I would *greatly* appreciate any feedback from anyone who has experience
>>> with this.  If I can get some confirmation on my plan, I'd be happy to add
>>> it to the wiki, even if it's just a page that points to the database
>>> backup/restore.  I believe that this would be the same procedure regardless
>>> of if you're re-installing the OS vs. upgrading/moving to new hardware.
>>>       
>> That sounds pretty sound, but others will tell you if you have missed
>> something major.
>>
>> My only tip is to unplug the 160GB drive during the install, just in
>> CASE you or the installer accidentally format it.
> Further thought - the dB also has all your tuner settings so they
> should be restored too.
>
> Other thing to watch is version change - you really want to be keeping
> the database schema the same, or going to a later version.

Right.  Good plan.

Important things to keep it simple:
    1) Use the /exact/ same hostname for the new system as you used for 
the old.
    2) If your capture cards change as a result of the new OS (i.e. new 
device number/order or different drivers), you'll need to clear them and 
re-create them.  Do that with the Capture Card portion of 
http://www.gossamer-threads.com/lists/mythtv/users/264034#264034 .

If you do the above, everything should just work as if nothing 
changed--assuming, of course, the new MythTV is the same or later 
version than the old.

If you can't use the same hostname, make sure you do a hostname change ( 
http://www.mythtv.org/wiki/Database_Backup_and_Restore#Change_the_hostname_of_a_MythTV_frontend_or_backend 
) using the restore script /at the right time/...  I.e. right after you 
restore the DB (without specifying the hostname change), do the hostname 
change.  Do *not* run /any/ mythtv programs (mythtv-setup, mythbackend, 
mythfrontend) against the restored database before doing the hostname 
change or you will make a mess that will require a /lot/ of work to 
clean up.

Mike