1.\" $KAME: ifmcstat.8,v 1.6 2002/10/31 04:23:43 suz Exp $ 2.\" 3.\" Copyright (c) 2007-2009 Bruce Simpson. 4.\" Copyright (C) 1995, 1996, 1997, 1998, and 1999 WIDE Project. 5.\" All rights reserved. 6.\" 7.\" Redistribution and use in source and binary forms, with or without 8.\" modification, are permitted provided that the following conditions 9.\" are met: 10.\" 1. Redistributions of source code must retain the above copyright 11.\" notice, this list of conditions and the following disclaimer. 12.\" 2. Redistributions in binary form must reproduce the above copyright 13.\" notice, this list of conditions and the following disclaimer in the 14.\" documentation and/or other materials provided with the distribution. 15.\" 3. Neither the name of the project nor the names of its contributors 16.\" may be used to endorse or promote products derived from this software 17.\" without specific prior written permission. 18.\" 19.\" THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 20.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22.\" ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 23.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29.\" SUCH DAMAGE. 30.\" 31.Dd May 27, 2009 32.Dt IFMCSTAT 8 33.Os 34.Sh NAME 35.Nm ifmcstat 36.Nd dump multicast group management statistics per interface 37.Sh SYNOPSIS 38.Nm 39.Op Fl i Ar interface 40.Op Fl f Ar address-family 41.Op Fl v 42.Op Fl K 43.Op Fl M Ar core 44.Op Fl N Ar system 45.\" 46.Sh DESCRIPTION 47The 48.Nm 49command dumps multicast group information from the kernel. 50.Pp 51The following options are supported: 52.Bl -tag -width Fl 53.It Fl i Ar interface 54specifies the interface to be displayed. 55.It Fl f Ar address-family 56specifies the address family to be displayed; 57.Ar inet , 58.Ar inet6 59and 60.Ar link 61are supported. 62.It Fl v 63specifies that link-layer memberships should be printed; 64they are suppressed by default. 65It may not be specified for 66.Fl f Ar link . 67Source lists for each group will also be printed. 68.Pp 69If specified twice, and 70.Xr kvm 3 71is in use, the control plane timers for each interface 72and the source list counters for each group 73will also be printed. 74.El 75.Pp 76The following options are only available if 77.Nm 78has been built with support for 79.Xr kvm 3 : 80.Bl -tag -width Fl 81.It Fl K 82attempts to use 83.Xr kvm 3 84to retrieve the multicast group information. 85.It Fl M Ar core 86extracts values associated with the name list from the specified core, 87instead of the default 88.Pa /dev/kmem . 89.It Fl N Ar system 90extracts the name list from the specified kernel instead of the 91default, which is the kernel image the system has booted from. 92.El 93.Sh IMPLEMENTATION NOTES 94.Nm 95will always print the embedded scope IDs of IPv6 multicast group 96memberships. 97This is because memberships are always scoped to an interface. 98.Pp 99When run with the 100.Fl v 101option, 102.Nm 103may print multicast MAC addresses twice if they are 104referenced by a layer 3 protocol. 105.Pp 106When run with 107.Xr kvm 3 108support, 109the names of all interfaces configured in the system will be 110printed in the first column of output, even if no multicast 111group memberships are present on those interfaces. 112The output may also be slightly different, as the kernel 113data structures are being traversed with minimal post-processing 114of the output. 115.Pp 116When built without 117.Xr kvm 3 118support, the information displayed by 119.Nm 120is more limited. 121This support is recommended for debugging purposes. 122It requires super-user privilege if used to inspect a running kernel. 123.Sh SEE ALSO 124.Xr netstat 1 , 125.Xr getifaddrs 3 , 126.Xr getifmaddrs 3 , 127.Xr kvm 3 128