Beefy Boxes and Bandwidth Generously Provided by pair Networks
Clear questions and runnable code
get the best and fastest answer
 
PerlMonks  

Re^3: Same multicast packet received by multiple NICs

by Illuminatus (Curate)
on Jun 02, 2012 at 00:42 UTC ( #973900=note: print w/ replies, xml ) Need Help??


in reply to Re^2: Same multicast packet received by multiple NICs
in thread Same multicast packet received by multiple NICs

It may depend on your OS. This module creates a socket of type SOCK_DGRAM. These route at the IP/UDP level. I know the module says it can limit you to what's on one NIC, but I'm pretty sure on Linux there's no way to enforce this. The point of multicast is to deliver to every endpoint using that destination address. Maybe the Windows stack has hooks to limit this. I am curious as to why you need to listen for the mcast traffic on a socket if you're using tcpdump to see them as well. You can pass a filter to tcpdump to only see what you're looking for.

fnord


Comment on Re^3: Same multicast packet received by multiple NICs
Re^4: Same multicast packet received by multiple NICs
by sophate (Beadle) on Jun 02, 2012 at 17:15 UTC

    Hi, the socket is actually for joining the mcast group to draw the traffic into the NIC. Tcpdump is just for watching if there are any packets flowing through the NIC. Correct me if I'm wrong, I can't join a mcast group with just topdump :-)

Log In?
Username:
Password:

What's my password?
Create A New User
Node Status?
node history
Node Type: note [id://973900]
help
Chatterbox?
and the web crawler heard nothing...

How do I use this? | Other CB clients
Other Users?
Others chanting in the Monastery: (13)
As of 2014-07-23 18:10 GMT
Sections?
Information?
Find Nodes?
Leftovers?
    Voting Booth?

    My favorite superfluous repetitious redundant duplicative phrase is:









    Results (148 votes), past polls