I'm thinking that we might be seeing issues with DHCP and DLNA devices showing up in MC.
MC caches the existing DLNA devices when it sees them so next time it starts up it can show the zones that were there when the program closed.
Now that should be fine unless the IP address of the renderer changes. If that happens and you try pushing something to the device, it will hang for a while and come back with the "unable to control..." message. At that point the device will be flushed from the Zone list and should reappear when it sends another broadcast.
Now there are different approaches to handling this. The Sony media player device takes the most harsh route and make you pre-approve the servers before you can use them. If the address changes, you'll see two and will have to inactivate one and activate the other. On the other extreme, a PS3 or WD constantly chatter and generally add and remove the devices promptly (unless they go off the air without saying so).
To avoid the extra chatter (really just did this intuitively) I set the renderers and servers in my house to fixed addresses. You can often do this on the device (but not always) or via a fixed DHCP lease in your router (which uses the MAC address of your device to always hand out the same address).
Most of the devices we test here are like that as well since it makes tracing with wireshark easier.
I know the whole idea of the SSDP is to make dynamic discovery with varying addresses work but I think the various implementations show that we should try to minimize the amount of things that have to go perfectly in the process of finding and using devices (and I assume that's why Sony for example takes their approach on their Media Server).
Thoughts?
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Topic: Thoughts on DLNA devices, MC and DHCP (Read 1163 times)