The VideoLAN Forums

Hi people.

I have a huge problem trying to get VLC to display a multicast stream on Lucid Lynx. This has worked with VLC on Windows (but sadly I don't have a windows machine anymore).

The thing just stops at "pre buffering" but I can actually see MPEG stream coming in on the interface through Wireshark.


This is the output:
./vlc -vvv -I dummy udp://@239.255.4.2:5002

VLC media player 1.2.0-git Twoflower (revision 1.1.0-pre1-1092-g2298f38)
[0x1cc9540] main libvlc debug: VLC media player - 1.2.0-git Twoflower
[0x1cc9540] main libvlc debug: Copyright © 1996-2010 the VideoLAN team
[0x1cc9540] main libvlc debug: revision 1.1.0-pre1-1092-g2298f38
[0x1cc9540] main libvlc debug: configured with ./configure '--disable-qt4' '--disable-skins2'
[0x1cc9540] main libvlc debug: translation test: code is "C"
[0x1cc9540] main libvlc debug: checking plugin modules
[0x1cc9540] main libvlc debug: loading plugins cache file /usr/src/vlc/src/.libs/vlc/plugins/plugins-04081e-3e8.dat
[0x1cc9540] main libvlc warning: cannot read /usr/src/vlc/src/.libs/vlc/plugins/plugins-04081e-3e8.dat (No such file or directory)
[0x1cc9540] main libvlc debug: recursively browsing `/usr/src/vlc/src/.libs/vlc/plugins'
[0x1cc9540] main libvlc debug: saving plugins cache /usr/src/vlc/src/.libs/vlc/plugins/plugins-04081e-3e8.dat
[0x1cc9540] main libvlc debug: loading plugins cache file /usr/src/vlc/modules/plugins-04081e-3e8.dat
[0x1cc9540] main libvlc debug: recursively browsing `/usr/src/vlc/modules'
[0x1cc9540] main libvlc debug: saving plugins cache /usr/src/vlc/modules/plugins-04081e-3e8.dat
[0x1cc9540] main libvlc debug: module bank initialized (374 modules)
[0x1cc9540] main libvlc debug: opening config file (/home/user/.config/vlc/vlcrc)
[0x1cc9540] main libvlc debug: CPU has capabilities MMX MMXEXT SSE SSE2 SSE3 SSSE3 FPU
[0x1cc9540] main libvlc debug: looking for memcpy module: 3 candidates
[0x1cc9540] main libvlc debug: using memcpy module "memcpymmxext"
[0x1d89090] main input debug: Creating an input for 'Media Library'
[0x1d89090] main input debug: Input is a meta file: disabling unneeded options
[0x1d89090] main input debug: using timeshift granularity of 50 MiB
[0x1d89090] main input debug: using timeshift path '/tmp'
[0x1d89090] main input debug: `file/xspf-open:///home/user/.local/share/vlc/ml.xspf' gives access `file' demux `xspf-open' path `/home/user/.local/share/vlc/ml.xspf'
[0x1d89090] main input debug: creating demux: access='file' demux='xspf-open' path='/home/user/.local/share/vlc/ml.xspf'
[0x1d8cec0] main demux debug: looking for access_demux module: 1 candidate
[0x1d8cec0] main demux debug: no access_demux module matching "file" could be loaded
[0x1d8cec0] main demux debug: TIMER module_need() : 0.201 ms - Total 0.201 ms / 1 intvls (Avg 0.201 ms)
[0x1d89090] main input debug: creating access 'file' location='/home/user/.local/share/vlc/ml.xspf', path='/home/user/.local/share/vlc/ml.xspf'
[0x1d8db60] main access debug: looking for access module: 2 candidates
[0x1d8db60] filesystem access debug: opening file `/home/user/.local/share/vlc/ml.xspf'
[0x1d8db60] main access debug: using access module "filesystem"
[0x1d8db60] main access debug: TIMER module_need() : 0.286 ms - Total 0.286 ms / 1 intvls (Avg 0.286 ms)
[0x1d901b0] main stream debug: Using AStream*Stream
[0x1d901b0] main stream debug: pre buffering 1
[0x1d901b0] main stream debug: received first data after 0 ms
[0x1d901b0] main stream debug: pre-buffering done 296 bytes in 0s - 8759 KiB/s
[0x1d8d990] main stream debug: looking for stream_filter module: 5 candidates
[0x1d8d990] main stream debug: no stream_filter module matching "any" could be loaded
[0x1d8d990] main stream debug: TIMER module_need() : 0.480 ms - Total 0.480 ms / 1 intvls (Avg 0.480 ms)
[0x1d8d990] main stream debug: looking for stream_filter module: 1 candidate
[0x1d8d990] main stream debug: using stream_filter module "stream_filter_record"
[0x1d8d990] main stream debug: TIMER module_need() : 0.151 ms - Total 0.151 ms / 1 intvls (Avg 0.151 ms)
[0x1d89090] main input debug: creating demux: access='file' demux='xspf-open' path='/home/user/.local/share/vlc/ml.xspf'
[0x1d8e8d0] main demux debug: looking for demux module: 1 candidate
[0x1d8e8d0] playlist demux debug: using XSPF playlist reader
[0x1d8e8d0] main demux debug: using demux module "playlist"
[0x1d8e8d0] main demux debug: TIMER module_need() : 0.233 ms - Total 0.233 ms / 1 intvls (Avg 0.233 ms)
[0x1d8eee0] main demux meta debug: looking for meta reader module: 2 candidates
[0x1d8eee0] lua demux meta debug: Trying Lua scripts in /home/user/.local/share/vlc/lua/meta/reader
[0x1d8eee0] lua demux meta debug: Trying Lua scripts in /usr/local/lib/vlc/lua/meta/reader
[0x1d8eee0] lua demux meta debug: Trying Lua scripts in /usr/src/vlc/share/lua/meta/reader
[0x1d8eee0] lua demux meta debug: Trying Lua playlist script /usr/src/vlc/share/lua/meta/reader/filename.lua
[0x1d8eee0] lua demux meta debug: Trying Lua playlist script /usr/src/vlc/share/lua/meta/reader/filename.luac
[0x1d8eee0] main demux meta debug: no meta reader module matching "any" could be loaded
[0x1d8eee0] main demux meta debug: TIMER module_need() : 3.989 ms - Total 3.989 ms / 1 intvls (Avg 3.989 ms)
[0x1d89090] main input debug: `file/xspf-open:///home/user/.local/share/vlc/ml.xspf' successfully opened
[0x1d8eee0] main xml debug: looking for xml module: 2 candidates
[0x1d8eee0] main xml debug: using xml module "xml"
[0x1d8eee0] main xml debug: TIMER module_need() : 0.680 ms - Total 0.680 ms / 1 intvls (Avg 0.680 ms)
[0x1d8e8d0] playlist demux debug: parsed 0 tracks successfully
[0x1d8eee0] main xml debug: removing module "xml"
[0x1d89090] main input debug: EOF reached
[0x1d8e8d0] main demux debug: removing module "playlist"
[0x1d8d990] main stream debug: removing module "stream_filter_record"
[0x1d8db60] main access debug: removing module "filesystem"
[0x1d89090] main input debug: TIMER input launching for 'Media Library' : 5.842 ms - Total 5.842 ms / 1 intvls (Avg 5.842 ms)
[0x1d8c290] main interface debug: looking for interface module: 1 candidate
[0x1d8c290] main interface debug: using interface module "hotkeys"
[0x1d8c290] main interface debug: TIMER module_need() : 0.488 ms - Total 0.488 ms / 1 intvls (Avg 0.488 ms)
[0x1d8ada0] main interface debug: looking for interface module: 1 candidate
Blocked: call to unsetenv("DBUS_ACTIVATION_ADDRESS")
Blocked: call to unsetenv("DBUS_ACTIVATION_BUS_TYPE")
[0x1cdb0a0] main playlist debug: Activated
[0x1d8ada0] main interface debug: using interface module "inhibit"
[0x1d8ada0] main interface debug: TIMER module_need() : 2.694 ms - Total 2.694 ms / 1 intvls (Avg 2.694 ms)
[0x1cdb0a0] main playlist debug: adding item `udp://239.255.4.2:5002' ( udp://@239.255.4.2:5002 )
[0x1d8a4d0] main interface debug: looking for interface module: 1 candidate
[0x1cdb0a0] main playlist debug: rebuilding array of current - root Playlist
[0x1cdb0a0] main playlist debug: rebuild done - 1 items, index -1
[0x1d8a4d0] main interface debug: using interface module "globalhotkeys"
[0x1d8a4d0] main interface debug: TIMER module_need() : 5.436 ms - Total 5.436 ms / 1 intvls (Avg 5.436 ms)
[0x1dafe10] main interface debug: looking for interface module: 1 candidate
[0x1dafe10] dummy interface: using the dummy interface module...
[0x1dafe10] main interface debug: using interface module "dummy"
[0x1dafe10] main interface debug: TIMER module_need() : 0.283 ms - Total 0.283 ms / 1 intvls (Avg 0.283 ms)
[0x1cdb0a0] main playlist debug: processing request item null node Playlist skip 0
[0x1cdb0a0] main playlist debug: starting new item
[0x1cdb0a0] main playlist debug: creating new input thread
[0x1db0180] main input debug: Creating an input for 'udp://239.255.4.2:5002'
[0x1db0180] main input debug: thread (input) created at priority 10 (input/input.c:214)
[0x1db0180] main input debug: thread started
[0x1db0180] main input debug: using timeshift granularity of 50 MiB
[0x1db0180] main input debug: using timeshift path '/tmp'
[0x1db0180] main input debug: `udp://@239.255.4.2:5002' gives access `udp' demux `' path `@239.255.4.2:5002'
[0x1db0180] main input debug: creating demux: access='udp' demux='' path='@239.255.4.2:5002'
[0x1dad860] main demux debug: looking for access_demux module: 0 candidates
[0x1dad860] main demux debug: no access_demux module matched "udp"
[0x1dad860] main demux debug: TIMER module_need() : 0.096 ms - Total 0.096 ms / 1 intvls (Avg 0.096 ms)
[0x1db0180] main input debug: creating access 'udp' location='@239.255.4.2:5002', path='(null)'
[0x1dadbf0] main access debug: looking for access module: 1 candidate
[0x1dadbf0] access_udp access debug: opening server=:0 local=239.255.4.2:5002
[0x1dadbf0] main access debug: net: opening 239.255.4.2 datagram port 5002
[0x1dadbf0] main access debug: Multicast group join request
[0x1dadbf0] main access debug: using access module "access_udp"
[0x1dadbf0] main access debug: TIMER module_need() : 0.940 ms - Total 0.940 ms / 1 intvls (Avg 0.940 ms)
[0x1dae480] main stream debug: Using AStream*Block
[0x1dae480] main stream debug: pre buffering





I have tried the VLC version:
- that comes by default with ubuntu
- from a ppa
VLC media player 1.1.0 The Luggage (revision exported)
VLC version 1.1.0 The Luggage (exported)
Compiled by buildd on platinum.ppa (Jun 28 2010 16:35:25)
Kodni prevajalnik: gcc version 4.4.3 (Ubuntu 4.4.3-4ubuntu5)


- from git
VLC media player 1.1.0 The Luggage (revision exported)
VLC version 1.1.0 The Luggage (exported)
Compiled by buildd on platinum.ppa (Jun 28 2010 16:35:25)
Kodni prevajalnik: gcc version 4.4.3 (Ubuntu 4.4.3-4ubuntu5)



By putting in some debbuging in the code, I have found out that it blocks here:
p_block = p_access->pf_block( p_access );

in method static block_t *AReadBlock( stream_t *s, bool *pb_eof )

My knowledge of C stops here but I have seen similar posts over the web without any real answer. Any ideas?

VLC is not receiving any data. Make sure your network is configured correctly, the multicast address is correct, and you did not firewall your own self.

But I did!

As I said:
- I can see the packets coming (in Wireshark)
- I've disabled all other network interfaces except for eth0
- I've forced a route of multicast to eth0 (route add -net 239.255.4.0 netmask 255.255.255.0 eth0)

I have no firewall:
iptables -L
Chain INPUT (policy ACCEPT)
target prot opt source destination

Chain FORWARD (policy ACCEPT)
target prot opt source destination

Chain OUTPUT (policy ACCEPT)
target prot opt source destination


That's why I don't understand what's going on. What else could be wrong -- what can I check?

Found it, finally, for reference:

Found it!
It actually was the rp_filter setting. In 2.6.31, rp_filter calculation code was changed, see: http://linux.derkeiler.com/Mailing-List ... 04929.html

Anyway, I originally had in my /etc/conf.d/local.start:
echo 0 > /proc/sys/net/ipv4/conf/all/rp_filter
echo 0 > /proc/sys/net/ipv4/conf/default/rp_filter

I guess that wasn't good enough, so I instead put those in /etc/sysctl.conf (better place anyway), and put this in local.start instead:
echo 0 > /proc/sys/net/ipv4/conf/eth0/rp_filter
echo 0 > /proc/sys/net/ipv4/conf/eth1/rp_filter
echo 0 > /proc/sys/net/ipv4/conf/lo/rp_filter


From: http://forums.gentoo.org/viewtopic-p-62 ... 19f0dc79af