[mythtv-users] Removable storage with MythTV

[Fedor Pikus]

On 8/8/05, Ryan Steffes <rbsteffes at gmail.com> wrote:
> 
> 
> On 8/6/05, Eileen Webb <eileen.webb at gmail.com> wrote:
> > Hi all,
> > I've just started building my Myth system and wanted to run an idea by
> more experienced users to make sure I'm not crazy.
> > 
> > Here's the story:  I live out in the middle of nowhere where the only TV
> that exists is satellite (DirecTV, in our area).  I have some family moving
> nearby who is going to get a system, which by default comes with FOUR
> set-top boxes!  Four is a lot of boxes for only two people, and they have
> graciously offered us the use of one of the extra boxes.
> > 
> > So I got this great idea that I'd set up a Myth system at their house,
> program it from my house (yeah for web interface!), and record myself some
> TV.  My plan is to have a two or three removable hard drives (actually, just
> some normal drives that are easy to access) and I would swap them around to
> record shows.  So stuff would get recorded onto driveA, then at some point
> I'd come by and swap it with driveB.  Then recording could continue on
> driveB and I'd take driveA home with me and watch it there.  The computer at
> home would also have Myth, so the file types and arrangements should still
> work, and I'll get to play with the game emulator, too!
> > 
> > Does this make sense?  Does it seem at all feasible?  From the outside, it
> seems pretty simple, but those are famous last words.  I would love any
> thoughts on this plan -- tips from anyone who has done anything similar,
> horror stories on why I am doomed, whatever.
> > 
>  
>  Based purely on what I've seen, there's potential for this to work.  MythTV
> seems to fail fairly gracefully if the file it's looking for isn't found. 
> On the theme I'm using (not sure if this is true for all themes), the show
> name appears dimmer, but not quite greyed out if the file isn't found.
>  
>  I'd think to make this work somewhat efficiently, all you'd need to do is
> to make a dump of the recorded table, at their place and restore it when you
> load the hard drive at your place.  Then, optionally, you could tell the
> backend at their place to delete all the recordings.
>  
>  There may be a reason why this wouldn't work, but I can't think of it off
> hand.

Another option is to set up a mirroring software raid, and pull one
disk out of it. Myth will not need to fail at all, gracefully or
otherwise. SoftRAID normally does not automatically add new drives
after they fail (removal qualifies as failure in this context) but
since you expect it to always "fail" in the same way, wou can set up
boot scripts to properly insert the disk into the array. For example,
if one computer is always the source and the other is always the
destination, you'd set up the source to always add new disk as dirty
and treat existing disks as current, and the destination to always
treat new disk as current and update its permanent disk.
This way, you pull the disk out of source computer, life goes on. You
plug it into destination, RAID reconstructs, now you have your
destination disk updated. You take the drive out of destination, it
stays as the mirror of the source disk until you update it again.
-- 
Fedor G Pikus (fpikus at gmail.com)
http://www.pikus.net
http://wild-light.com