Am 19.12.2013 um 16:29 schrieb jannik.laval <[email protected]>:
> Ok, here is my situation: > > - I have a Lego Mindstorm that broadcast a UDP message every 10 seconds. > - With Wireshark I can see the UDP message, so no problem with that. > - I tried to set the option SO_BROADCAST, it does not work anymore. > > Any other idea ? > What operating system are you using? Norbert > Jannik > > On Dec 19, 2013, at 4:14 PM, Stephan Eggermont <[email protected]> wrote: > >> Norbert wrote: >> >To send or receive a broadcast packet you need to put special options on >> >the socket on the native side (setsockopt). You need to >look if the >> >SO_BROADCAST option is mentioned anywhere. If not it won’t work without >> >adding them. And for sending them you >need almost special privileges on >> >the system. This is not a „user feature“. >> >> And even though it is "the right thing" for lots of situations, your network >> is also very likely to not do the right thing >> with broadcast packets. Etsy decided on using bittorrent protocol to update >> their production servers indexes, because they >> found it too difficult to get their network to do the right thing. They >> found that their switches were basically livelocked >> while dealing with broadcast packets. >> >> http://codeascraft.com/2012/01/23/solr-bittorrent-index-replication/ >> >> If you want the broadcast to travel a little further, the routers need to be >> configured not to drop the packets. >> >> Stephan >
