Question / Help OBS NGINX-RTMP 10 PC Setup

[gloom315]

Hi Folks,

Hoping to get some feedback here. My friends and I have a group where we LAN usually monthly together. We did Extra Life together.

Everyone had OBS Classic installed, streaming to an RTMP server, then another computer running OBS classic to pull the streams and control what's going to our twitch channel.

Hardware list is:

16 port Gb switch
1 Dell Optiplex 990, 16GB of RAM, 1Gb NIC, Core i7 2600, 250GB 7.2kRPM HDD running Ubuntu with rtmp/nginx
1 Dell Optiplex 990, 16GB of RAM, 1Gb NIC, Core i7 2600, 250GB 7.2kRPM HDD running Win 7 Pro with OBS Classic and vid plug-in

Then everyone else's PC.

Everyone gets their own scene in OBS and when unattended, I use an auto-hotkey script to swap between them. The problem I run into is that 1-3 PCs seem to come up black when I try to load them. They either don't come up at all or come up with a significant delay compared to others. Strangely at times, it works perfectly fine too.

Some strange audio level issues too occasionally.

As far as I can tell, neither of the two PCs are under any significant stress or running out of resources.

I'm open to suggestions on how to improve/fix this setup. We don't stream often enough to warrant a significant investment in new gear. If anyone has any experience with large LANs that stream, I'd love to hear from you as well.

Thanks!

 

[dping]

Hi Folks,

Hoping to get some feedback here. My friends and I have a group where we LAN usually monthly together. We did Extra Life together.

Everyone had OBS Classic installed, streaming to an RTMP server, then another computer running OBS classic to pull the streams and control what's going to our twitch channel.

Hardware list is:

16 port Gb switch
1 Dell Optiplex 990, 16GB of RAM, 1Gb NIC, Core i7 2600, 250GB 7.2kRPM HDD running Ubuntu with rtmp/nginx
1 Dell Optiplex 990, 16GB of RAM, 1Gb NIC, Core i7 2600, 250GB 7.2kRPM HDD running Win 7 Pro with OBS Classic and vid plug-in

Then everyone else's PC.

Everyone gets their own scene in OBS and when unattended, I use an auto-hotkey script to swap between them. The problem I run into is that 1-3 PCs seem to come up black when I try to load them. They either don't come up at all or come up with a significant delay compared to others. Strangely at times, it works perfectly fine too.

Some strange audio level issues too occasionally.

As far as I can tell, neither of the two PCs are under any significant stress or running out of resources.

I'm open to suggestions on how to improve/fix this setup. We don't stream often enough to warrant a significant investment in new gear. If anyone has any experience with large LANs that stream, I'd love to hear from you as well.

Thanks!

What is the typical bitrate used for each streaming PC? do you have standard settings you have each one of them use?

do you have logfiles when and from the PCs having issues?

on the receiving end, do you have the log from that PC as well?

please label logs appropriately and maybe assign PC's number so later we can keep track of each. We can call your output stream something like output PC and the 16+ clients, client1, client2, etc.

 

[gloom315]

I don't have logs, I'll pull some this weekend at our LAN.

Everyone is using the settings that are meant for twitch, but instead of casting to twitch, I have them set up to go to our rtmp server.

 

[dping]

I don't have logs, I'll pull some this weekend at our LAN.

Everyone is using the settings that are meant for twitch, but instead of casting to twitch, I have them set up to go to our rtmp server.

Ideally. the clients on the LAN, you can have them make another profile that is more optimized for the LAN. something like 16mbps and there is an old trick to lower the buffer to basically give buffer space for 1 frame. and use low latency mode (maybe). so basically the bitrate is set higher but the buffer it set to process 1 frame then send it out.

so if each person streams at 30fps 720p with 16200 bitrate then your buffer would be something like 540 (1/30th of the bitrate). This could kill a little quality but latency would be much faster. and more consistent.

also have each of them set audio bitrate to 96kbps and ensure all audio devices on all PC are either usings 44100Hz or 48000Hz. 44100Hz would be better for all around compatibility. note that all audio devices in windows playback and recording devices would need to use this same format or expect issues. This means that all 16 client's mics, headsets and OBS instances. This includes the outgoing OBS instance.

 

[gloom315]

Ideally. the clients on the LAN, you can have them make another profile that is more optimized for the LAN. something like 16mbps and there is an old trick to lower the buffer to basically give buffer space for 1 frame. and use low latency mode (maybe). so basically the bitrate is set higher but the buffer it set to process 1 frame then send it out.

so if each person streams at 30fps 720p with 16200 bitrate then your buffer would be something like 540 (1/30th of the bitrate). This could kill a little quality but latency would be much faster. and more consistent.

also have each of them set audio bitrate to 96kbps and ensure all audio devices on all PC are either usings 44100Hz or 48000Hz. 44100Hz would be better for all around compatibility. note that all audio devices in windows playback and recording devices would need to use this same format or expect issues. This means that all 16 client's mics, headsets and OBS instances. This includes the outgoing OBS instance.

Thanks, this is very helpful. Will be putting this to use this weekend.

 

[dping]

Thanks, this is very helpful. Will be putting this to use this weekend.

Well with testing. the bitrate thing I would do outside of your stream first with 1PC going to NGINX to OBS output stream. then later add more, but definitely get the audio part in check.

the numbers I wrote are off the top of my head based on a 1500MTU LAN packet size which is around 12000bps. this way your packets are 100 full.

 

[dping]

@gloom315 curious on the progress you made lately.