Upnp Cannot be enabled on all Macbook Pros with Touchbars due to the iBridge network interface(en5)
Symptoms:
On two Macbook Pros with Touchbars (One 2017 13" and the other 2018 13"), VLC > Local Network > Universal Plug'n'Play will always display an empty list. The symptom is identical to what was reported in " https://trac.videolan.org/vlc/ticket/14526 " At the same time, in the same network, a Macbook Pro 2015' (without Touch bar) can successful see the list of UPNP servers in VLC.
On Macbook Pro Touch Bar ones, trying to right click "Universal Plug'n'Play" > Enable will generate the following Error Message output:
upnp info: Initializing libupnp on 'default' interface
upnp error: Initialization failed: UPNP_E_SOCKET_ERROR
main debug: no services_discovery modules matched
main error: no suitable services discovery module
The "enable" would fail, still showing the empty list.
Suspected Root Cause The error message seems to suggest an issue with multiple adapters. And Macbook Pro with Touchbars reserve iBridge (en5) to communicate with Touchbar (always active). Another interesting fact: the same MAC address (ac:de:48:00:11:22) for this interface is used on all Macs. As a result, VLC seems to land on the en5 adapter.
For comparison, specifc ifconfig output for en5 and en0(active wifi):
en5: flags=8863<UP,BROADCAST,SMART,RUNNING,SIMPLEX,MULTICAST> mtu 1500
ether ac:de:48:00:11:22
inet6 fe80::aede:48ff:fe00:1122%en5 prefixlen 64 scopeid 0x8
nd6 options=201<PERFORMNUD,DAD>
media: autoselect (100baseTX <full-duplex>)
status: active
en0: flags=8863<UP,BROADCAST,SMART,RUNNING,SIMPLEX,MULTICAST> mtu 1500
ether f0:18:98:16:xx:yy
inet6 fe80::1056:7ae0:ebdc:fc0c%en0 prefixlen 64 secured scopeid 0xa
inet6 2604:4080:100a:8120:14a1:bb2a:b0ec:eeee prefixlen 64 autoconf secured
inet6 2604:4080:100a:8120:9dca:47d8:c21e:4444 prefixlen 64 autoconf temporary
inet 192.168.1.58 netmask 0xffffff00 broadcast 192.168.1.255
nd6 options=201<PERFORMNUD,DAD>
media: autoselect
status: active
On the Macbook Pro without Touch Bar, the en5 does not exist. Therefore no problem was observed. btw. An issue with the same root cause was reported to Mac Minecraft: https://bugs.mojang.com/browse/MC-98598
Tested on Mac OS 10.13.6, 10.14, 10.14.1 beta. OS versions have no impact on results. Only Touch bar does. On Touch Bar models, tested vlc 2.0.8 (does not have the issue), vlc 3.0.4 stable (have the issue), vlc-git-4.0.0 (9/26/2018, having the issue).