Recording on NAS server

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alphatech69
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Recording on NAS server

Post by alphatech69 »

Firs post on this board. I have Mythtvubuntu installed on a VMWare machine. I also have a NAS QNAP. I have space on the Qnap and it is not over utilized while the VMVare has several machine on it. I was thinking if make sense to move the recording a live stream on my TV live utilizing HDHomerun on Qnap instead of the VMWare directory. If anyone has already done it, if they could show the syntax to enter in mythtv since I'm not that proficient in Linux but enough to do damage. There are any pro or con by using this strategy, I have RPI2 and finally I got the TV to work great with all these tools. My last question, am I correct to say that is mythtv actually passing the mp2 HDHomerun streaming to RPI2 and is not streaming directly to RPI2? Just a curiosity on the last topic.

Thanks for your help.
alphatech69
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Re: Recording on NAS server

Post by alphatech69 »

I guess is something that nobody knows how to do it or it does not make sense to do it, either way could you please give me your input, please.
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dekarl
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Re: Recording on NAS server

Post by dekarl »

MythTV will always transmit the stream from the HD Homerun to the backend that drives the recorder, store it there, and then to the frontend.
I have not seen a MythTV package for QNAP yet, but as a combination with a HDHR it sounds feasible.

You can also mount your NAS storage to you backend machine. Just be sure to add a directory inside the mount point instead of the mount point itself to your Storage Group.
alphatech69
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Re: Recording on NAS server

Post by alphatech69 »

Dekarl,
Very much appreciated it, your post was very detailed and easy to understand. If you not mind I have an additional questions.
Since I use livetv and hdhomerun, would the livetv file happen on the qnap and not on MythTV server? I want to minimize writing twice to disks since livetv is a real time broadcast. I noticed that you are really an expert here so what would you do in my case? I was thinking of store the recording on qnap and keep livetv on the virtual machine MythTV. MythTV is a fantastic product but a little intimidating, I want to make sure I do the right thing. I read about storage, it alone is overwhelming.
Thanks again for your help.
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dekarl
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Re: Recording on NAS server

Post by dekarl »

alphatech69 wrote:Since I use livetv and hdhomerun, would the livetv file happen on the qnap and not on MythTV server? I want to minimize writing twice to disks since livetv is a real time broadcast.
MythTV should write to disk only once. Either locally to the VM or "locally" to the NFS mounted NAS. As MythTV adds content-on-demand trick play (things like pausing, slow playing, skipping around) on top of the live-media-broadcast we have to store the stream somewhere.
alphatech69 wrote:I was thinking of store the recording on qnap and keep livetv on the virtual machine MythTV.
You can manually add a special "LiveTV" storage group with "VM" storage in addition to the "Default" storage group with "NAS" storage.
Eventually Mythbuntu already set you up with a "LiveTV" SG pointing at /var/lib/mythtv/livetv/ of your VM storage. If that is the case then your target layout would be something like this:
  • /var/lib/mythtv - an empty directory to mount your NAS storage to. The current content, especially the directories that are configured in your Storage Groups, would be move over to the NAS volume. The effect is, that should your backend VM ever be unable to mount the NAS volume then the MythTV backend process will not find its storage directories and fail to start instead of filling your VM storage without you knowing.
  • /var/lib/another-mythtv-e-g-mythtv2 - a main directory next to your existing one. This contains only a directory called "livetv" and may or may not be a special mount point. This "livetv" directory should be the only directory listed in the "livetv" SG.
alphatech69
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Re: Recording on NAS server

Post by alphatech69 »

You have the ability to explain things so complicated in a way that even I have easy time to understand them.
I'm not in front of MythTV and going by memory, because I have hdhomerun prime broadcasting up to 3 channels, would/should I setup 3 directories, one for each channel, even one on the local vm to off load the writing on disk?
I have been reading about NFS, Unfortunately there are may way to create it, do you have the best syntax for it, I. E tcp Vs udp, buffering and etc.

Thanks again and sorry to bother you so much.
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dekarl
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Re: Recording on NAS server

Post by dekarl »

Sorry, I can't help you with detailed VM storage and NFS information. I only use plain old local storage. One filesystem per disk, all inside one Storage Group.
Just one directory for all recorders is plenty. (you are looking at about 3x 20mbit/s maximum) Personally I would not start to micro manage the storage to much. Maybe keep the database and livetv/recordings on different disks, but thats about it. I'd try with everything on the NAS first, as your LiveTV storage may grow big. (And because its simpler that way.) I vaguely remember reports of people mounting their NAS via Samba successfully.

Btw, recently a Kodi Addon for newer HDHR models was released. This may or may not be interesting for LiveTV users.
alphatech69
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Re: Recording on NAS server

Post by alphatech69 »

Thank you very much that helped a lot.
alphatech69
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Re: Recording on NAS server

Post by alphatech69 »

An extra note, I tested the hdhomerun plug in, interesting enough on hd channels I get problems with audio and video which I lose audio and get pixel video. I tested several pvr, MythTV is one of the few that is able to give me smooth video and audio. I would assume that hdhomerun plug-in would be better since it is directly taking the stream files from the box, go figure [emoji1]
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