mcgrab.1 revision 307403
Copyright (c) 2008 George V. Neville-Neil
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$FreeBSD: stable/10/tools/tools/mcgrab/mcgrab.1 307403 2016-10-16 22:02:50Z sevan $

.Dd July 9, 2008 .Dt MCGRAB 1 .Os .Sh NAME .Nm mcgrab .Nd "multicast filter overload test" .Sh SYNOPSIS .Nm .Op Fl i Ar interface .Op Fl g Ar group .Op Fl n Ar number .Sh DESCRIPTION The .Nm command implements a multicast test which grabs and holds N multicast addresses. The purpose of the test is to see what happens when a network interface is no longer able to filter multicasts in hardware and has to switch to promiscuous or multicast promiscuous mode. A successful test does not have any result, but an unsuccessful test will have deleterious side effects. Packet size in bytes. The options are as follows: l -tag -width ".Fl i Ar interface" t Fl i Ar interface Network interface, which can be found with .Xr ifconfig 8 . t Fl g Ar group Multicast group. t Fl n Ar number Number of groups to join. .El .Sh EXAMPLES The following is an example of a typical usage of the .Nm command:

p .Dl "mcgrab -i em0 -g 239.255.255.1 -n 1024" .Sh SEE ALSO .Xr mctest 1 , .Xr netstat 1 , .Xr nanosleep 2 , .Xr ifconfig 8 .Sh HISTORY The .Nm program first appeared in .Fx 7.0 . .Sh AUTHORS This manual page was written by .An George V. Neville-Neil Aq Mt gnn@FreeBSD.org . .Sh BUGS Should be reported to the author or to .Aq Mt net@FreeBSD.org .