There were a long-standing issue at home that my DLNA clients frequently lost connectivity with the DLNA servers. One of the DLNA servers is a NAS in which I place media files to be served over DLNA to TV, desktop and mobile etc. I did a tcpdump on the NAS and saw the NOTIFY messages to UPnP multicast as expected, but another Wireshark running on the desktop nearly never saw those multicast messages, and I confirmed that at that time there were no DLNA servers discovered by my other DLNA clients.
I noticed that there is an "Enable UPnP" option in the ASUS RT-AC87U router I use at home, which I previously set to disabled. I enabled it, and voila, I saw the multicast messages on my desktop and had no problem with DLNA browsing since.
My understanding is the disabling of UPnP at router is mostly a security consideration. I did a port scan test at GRC and apparently the router didn't respond to upnp on WAN, even though I switched upnp to enabled. Seems good.
So my questions.
1. Am I doing the right thing? So my expectation is the router should not have blocked the upnp related multicast messages in the LAN, so what I wanted to do is just to unblock it inside the LAN but NOT WAN. If I was doing the wrong thing, are there other approaches that allows me to achieve this without enabling UPnP at router?
2. What does that option do actually? For my use case, i.e. DLNA, I do not see directly why support from the router would be needed. All I see is that it looks like the DLNA devices go through some discovery messages over the LAN and then the rest are direct connections between them. Or did I misunderstand something?
Thanks!
I noticed that there is an "Enable UPnP" option in the ASUS RT-AC87U router I use at home, which I previously set to disabled. I enabled it, and voila, I saw the multicast messages on my desktop and had no problem with DLNA browsing since.
My understanding is the disabling of UPnP at router is mostly a security consideration. I did a port scan test at GRC and apparently the router didn't respond to upnp on WAN, even though I switched upnp to enabled. Seems good.
So my questions.
1. Am I doing the right thing? So my expectation is the router should not have blocked the upnp related multicast messages in the LAN, so what I wanted to do is just to unblock it inside the LAN but NOT WAN. If I was doing the wrong thing, are there other approaches that allows me to achieve this without enabling UPnP at router?
2. What does that option do actually? For my use case, i.e. DLNA, I do not see directly why support from the router would be needed. All I see is that it looks like the DLNA devices go through some discovery messages over the LAN and then the rest are direct connections between them. Or did I misunderstand something?
Thanks!