[mythtv-users] Can't find storage group to delete it

Michael T. Dean mtdean at thirdcontact.com
Tue May 26 10:58:49 UTC 2015


On 05/26/2015 06:36 AM, Robin Gilks wrote:
>> Hoi Robin,
>>
>> Tuesday, May 26, 2015, 10:39:52 AM, you wrote:
>>
>>
>>>>
>>>>
>>>>
>>>>> Where does the master backend (or slave) get the info if its not in
>>>>> the
>>>>> storagegroup table...
>>>>>
>>>> Are you sure it's a storage group and not a folder defined in the SB's
>>>> frontend's mythvideo settings?
>>>>
>>>> Yianni
>>>>
>>> Pretty sure - the frontend (on classic menu theme) TV/System
>>> Status/Machine Status show Mythtv Drive #1 which is on the master and
>>> Mythtv Drive #2 which is on the slave which shouldn't be using any
>>> storage.
>>> Both are reporting the same path but the details correspond to the
>>> actual
>>> master&  slave disk stats.
>> Does the path of a storagedirectory on the master exist on the slave?
>> I have this with an nfs directory.
>> The path where a storage directory on the master is mounted exists on
>> the slave. Even though on the slave nothing is mounted there. I
>> haven't taken action jet, because it's not used, but mythweb reports
>> it.
> Yup - the path is the same on both master and slave (/mnt/store).
>
> The master/mnt/store is the real 1.5Tb TV recording volume.
>
> The slave/mnt/store used to be used when that machine was the master but I
> *specifically* don't want it to be used now it is a slave - I want all
> storage on the master

Yes, what you're describing is how Storage Groups work.  Storage Groups 
specify a list of directories.  They are not confined to any particular 
host.  All Storage Groups are *defined* on the master backend, but apply 
to *all* hosts.

If you "define" (the word most people use, but completely incorrect) a 
Storage Group on a remote backend, you are actually overriding the 
already-defined list of directories for that Storage Group for that 
particular remote backend host (and only that host).  Therefore, there 
is almost never a reason to "define"--actually override--a Storage Group 
on any backend host.  There are much cleaner ways to use Storage Groups 
than doing overrides (which will likely haunt your system when you start 
retiring hosts--at least they will if you don't properly retire them).  
Generally, you should only ever define any Storage Group on the master 
backend an no host in your system should have any override definitions.

> Trouble is the slave *IS* using an unconfigured volume (according to the
> storagegroup table anyway). If I unmount the disk on the slave it starts
> to fill up the root drive or if I write protect it the slave backend
> complains it can't write to it and fails to record anything.

If you do not override a Storage Group on a remote host, the Storage 
Group for that remote host will be the exact same list of directories 
specified on the master backend.  However, remember that the Storage 
Group is only a list of directories.  It is not a list of directories 
that must exist on hosts, but just a list of directories.  Therefore, 
generally, the master backend's Storage Group definition specifies the 
union of all directories that exist on the master and all remote 
systems, even if some of those directories do not exist on some of the 
systems.  Each system will check to see if the directory exists before 
using it.

So, the way for a particular host to not use a directory defined in a 
Storage Group is to not have that directory on its file system.  As you 
found, you can not stop MythTV from trying to use it by specifying file 
system permissions.  Its mere existence signifies you mean to use it.  
If you don't want to use it, make sure it doesn't exist on the host.  If 
you want a "non-writable" directory (a directory from which MythTV will 
read recordings, but will never write recordings), it has to be in a 
"non-writable" Storage Group (a Storage Group whose name is never 
specified by any recording rule).  See 
http://www.gossamer-threads.com/lists/mythtv/users/535888#535888 for 
details.

All that said, what exactly are you trying to do?  I wonder if you're 
making things more complex than they need to be.

Mike



More information about the mythtv-users mailing list