Direct communication between two Raspberries

    Hello LibreELEC-Friends,

    note that I am using in my question the acronyms RP1 and RP2 which means Raspberry Number 1 and Raspberry Number 2, respectively. Here my question: I would like to stream movies (iso files with a bit rate of around 110Mbit/s) from RP1 (this is my Media Server) to RP2 (this is my Media Player) via direct communication. All my movies are stored on a External SSD which is connected to RP1. See the picture below for a better understanding. What I have to do to run my movies on RP2?

    Thanks in advance and best regards Marco

    Edit: Why I want this setup? The first reason is i do not want all the cables, flashing lights and noises of my HDD's in my living room. Therefore I need Media-Server in the basement room and Media-Player in the living room separate. Furthermore, I guess that a direct communication (without any network switch or router in between) gives me the best performance I need.

    RP1: Raspberry Number 1, Media-Server:

    • Raspberry PI 4 B 8GB
    • openmediavault

    RP2: Raspberry Number 2, Media-Player:

    • Raspberry PI 4 B 8GB
    • LibreELEC (Matrix) 10.0.2

    Hello @chewitt,

    thanks for your help! Before I am going through your instruction above I did the following:

    1) I checked on RP1 and RP2 which static IP address they have:

    RP1 {no IP address configured}:

    RP2 {address 192.170.1.5, netmask 255.255.255.0, gateway 192.170.1.6}:

    Do you have any idea how I can configure RP1 to have a unique static IP within the same network as RP2?

    THX and BR Marco

    Two options:

    a) Configure a static IPv4 address in LE settings add-on (network) settings

    b) Configure the router with a static DHCP reservation for the MAC of each RPi device

    I would personally do 'B' because this means the DHCP assigned IP is persistent over reinstallations of the device and copy/pasting things to a router GUI is usually quicker than entering details with a remote control (nothing has a keyboard attached in my setup).

    Hello @chewitt,

    thanks again! I could solve it finally. I have choosen your first option:

    Quote

    a) Configure a static IPv4 address in LE settings add-on (network) settings

    Similar for openmediavault on RP1. There it was a bit complicated because I did that via the web interface while RP1 was connected to my Router. Finally, both RP1 and RP2 can communicate with each other via direct communication (peer-to-peer). I also could successfully sharing a folder with SMB on RP1 and include the shared folder into my RP2. Then, running a 4k60Hz movie with Kodi works as expected. THX!

    Here my network settings on RP1 and RP2:

    RP1: {address 192.170.1.6, netmask 255.255.255.0, gateway 192.170.1.5}

    RP2: {address 192.170.1.5, netmask 255.255.255.0, gateway 192.170.1.6}

    But, how can I change settings in openmediavault without web interface, since RP1 is not connected to my Router?

    No idea. To be honest it wasn't obvious that you were directly connecting the two RPi devices (not via a router) so I was expecting them to be in the same subnet and thus the OMV interface would be accessible.

    Its an interesting approach, but unless you are planning to add more nodes in I'm not to sure what you're trying to achieve. Why not just plug the SSD straight into RP2?

    I have no idea if this will work (mainly because I've not tried it) but two thoughts did occur 1) enable wifi on RP1 and use that to connect to the router or 2) pop a mini hub in, plug into RP1 and make the other connections through that that would allow the router to be part of the setup.

    Hello @LybsterKodi,

    thanks for help! I would choose your option 2.

    Quote

    pop a mini hub in, plug into RP1 and make the other connections through that that would allow the router to be part of the setup.

    But I am not sure if I understand you correctly. Do you mean like this: see picture below. Is this what you mean? If yes, I do not know if this would work because then both RP1 and RP2 are connected to my Router and are in the same subnet as my Router, right? But this is not what I want. i want clearly an separate system: direct communication or peer-to-peer. The reason for this is I want the maximum bitrate when I am streaming 4k60Hz iso files. I already tried it it works perfect (no buffering). But with this seperate system I an not able to access the openmediavault web interface.

    Yes, your diagram is what I meant by that option.

    Unfortunately, you seem to have conflicting requirements. You cannot have an isolated system with the two Pis and connect to one of them from outside of that system. Just can't be done.

    Its worth going back and looking at what you're trying to achieve. A few questions

    1. why do you want the separate file server, what is its purpose?

    2. why not connect the SSD directly to RP2 which WILL give you the maximum speed connection?

    3. what speed is actually needed to stream 4k60Hz iso files (someone else might be able to answer this because I can't)?

    Hello @LybsterKodi,

    Quote

    1. why do you want the separate file server, what is its purpose?

    2. why not connect the SSD directly to RP2 which WILL give you the maximum speed connection?

    3. what speed is actually needed to stream 4k60Hz iso files (someone else might be able to answer this because I can't)?

    my answers:

    1. because I have also some HDDs connected to the Media-Server (RP1). I do not like the noise, the cables, the flashing lights and the HDDs itself in my living room. I prefer to bring all the stuff down to my basement room.
    2. see answer 1
    3. I checked some action scenes of the 4k Movie "The Meg, 2018" with Kodi on my Media-Player (RP2). I could measure around 80 Mbit/s. But there are other movies with around 100 Mbit/s (like the Transformers movie series)

    Hello @LybsterKodi and @chewitt,

    only for your information: I do not need any more support from your side to this topic. Everything works perfect. Thanks for your help. However, I will not leave this thread without add all my findings. May this would help also other users.

    So coming back to my Main-Question at the beginning of this thread :)

    Question:

    • What I have to do to run my 4k movies on RP2?

    Answer:

    OptionA (Direct communication or PeerToPeer)

    • ToDo:
      1. configure static IP-address of RP1
      2. configure static IP-address of RP2
    • Setup:
    • Result: PERFECT (no issues so far)
    • Performance Test:


    OptionB (communication via network switch)

    • Setup:
    • Result: ... will add my result soon
    • Performance Test: ... will add my performance tests soon