On Mon, Oct 15, 2012 at 2:17 PM, Andreas Longwitz <[email protected]> wrote: > Hi, > >> as I said, I think 672 is a bit low, though I used 4096 for NetBSD (with a >> sysctl for runtime adjustment if necessary) and that is still potentially >> prone to error with larger packets (L2CAP MTU between 48-65535 bytes is >> valid) so I guess that requiring the application to set the buffer size is >> best practice.. > > I agree. > >>> Now I describe another problem with my ping test, I am not sure if this >>> problem concerns btpand too. If the ICMP packet must be fragmented, then the >>> first fragment ist lost on the tap interface (and can not be found by >>> tcpdump >>> running on this tap) if an ARP request is necessary. >>> ping -c 1 -s 1400 panserver >>> works all the time, >>> ping -c 1 -s 1600 panserver >>> only works if the ip address of panserver is in the arp cache. >> >> does the ARP request get sent out? > > Yes and the arp answer comes in. > >>> I did nothing special with the tap interface, it is included in my >>> "cloned_interfaces" in rc.conf and opened by btpand. >>> >>> Any ideas ? >> >> No, I confess. > > My problem was a phantom ! It seems to be normal behavior in any network > and has nothing to do with btpand or tap interface. This was a little > bit suprising to me but I have checked this on several networks. An > explanation for this was given on freebsd-net some years ago titled > Lost fragment when send to ip that need arp resolve. > > Thanks again for help!
just in case Author: emax Date: Thu Oct 18 16:34:00 2012 New Revision: 241699 URL: http://svn.freebsd.org/changeset/base/241699 Log: make sure that socket's send and receive buffers are properly sized Submitted by: Iain Hibbert plunky at rya-online dot net MFC after: 3 weeks Modified: head/usr.sbin/bluetooth/btpand/client.c head/usr.sbin/bluetooth/btpand/server.c thanks max _______________________________________________ [email protected] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-bluetooth To unsubscribe, send any mail to "[email protected]"
