mirror of
https://git.FreeBSD.org/src.git
synced 2024-12-22 11:17:19 +00:00
191 lines
5.2 KiB
Groff
191 lines
5.2 KiB
Groff
.\" Copyright 1996 Massachusetts Institute of Technology
|
|
.\"
|
|
.\" Permission to use, copy, modify, and distribute this software and
|
|
.\" its documentation for any purpose and without fee is hereby
|
|
.\" granted, provided that both the above copyright notice and this
|
|
.\" permission notice appear in all copies, that both the above
|
|
.\" copyright notice and this permission notice appear in all
|
|
.\" supporting documentation, and that the name of M.I.T. not be used
|
|
.\" in advertising or publicity pertaining to distribution of the
|
|
.\" software without specific, written prior permission. M.I.T. makes
|
|
.\" no representations about the suitability of this software for any
|
|
.\" purpose. It is provided "as is" without express or implied
|
|
.\" warranty.
|
|
.\"
|
|
.\" THIS SOFTWARE IS PROVIDED BY M.I.T. ``AS IS''. M.I.T. DISCLAIMS
|
|
.\" ALL EXPRESS OR IMPLIED WARRANTIES WITH REGARD TO THIS SOFTWARE,
|
|
.\" INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
|
|
.\" MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT
|
|
.\" SHALL M.I.T. BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
|
|
.\" SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
|
|
.\" LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
|
|
.\" USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
|
|
.\" ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
|
|
.\" OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
|
|
.\" OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
.\" SUCH DAMAGE.
|
|
.\"
|
|
.\" $FreeBSD$
|
|
.\"
|
|
.Dd October 28, 2009
|
|
.Dt IFMIB 4
|
|
.Os
|
|
.Sh NAME
|
|
.Nm ifmib
|
|
.Nd Management Information Base for network interfaces
|
|
.Sh SYNOPSIS
|
|
.In sys/types.h
|
|
.In sys/socket.h
|
|
.In sys/sysctl.h
|
|
.In sys/time.h
|
|
.In net/if.h
|
|
.In net/if_mib.h
|
|
.Sh DESCRIPTION
|
|
The
|
|
.Nm
|
|
facility is an application of the
|
|
.Xr sysctl 3
|
|
interface to provide management information about network interfaces
|
|
to client applications such as
|
|
.Xr netstat 1 ,
|
|
.Xr slstat 8 ,
|
|
and
|
|
.Tn SNMP
|
|
management agents.
|
|
This information is structured as a table, where
|
|
each row in the table represents a logical network interface (either a
|
|
hardware device or a software pseudo-device like
|
|
.Xr lo 4 ) .
|
|
There are two columns in the table, each containing a single
|
|
structure: one column contains generic information relevant to all
|
|
interfaces, and the other contains information specific to the
|
|
particular class of interface.
|
|
(Generally the latter will implement
|
|
the
|
|
.Tn SNMP
|
|
.Tn MIB
|
|
defined for that particular interface class, if one exists and can be
|
|
implemented in the kernel.)
|
|
.Pp
|
|
The
|
|
.Nm
|
|
facility is accessed via the
|
|
.Dq Li net.link.generic
|
|
branch of the
|
|
.Xr sysctl 3
|
|
MIB.
|
|
The manifest constants for each level in the
|
|
.Xr sysctl 3
|
|
.Ar name
|
|
are defined in
|
|
.In net/if_mib.h .
|
|
The index of the last row in the table is given by
|
|
.Dq Li net.link.generic.system.ifcount
|
|
(or, using the manifest constants,
|
|
.Dv CTL_NET ,
|
|
.Dv PF_LINK ,
|
|
.Dv NETLINK_GENERIC ,
|
|
.Dv IFMIB_SYSTEM ,
|
|
.Dv IFMIB_IFCOUNT ) .
|
|
A management application searching for a particular interface should
|
|
start with row 1 and continue through the table row-by-row until the
|
|
desired interface is found, or the interface count is reached.
|
|
Note that the table may be sparse, i.e., a given row may not exist,
|
|
indicated by an
|
|
.Va errno
|
|
of
|
|
.Er ENOENT .
|
|
Such an error should be ignored, and the next row should be checked.
|
|
.Pp
|
|
The generic interface information, common to all interfaces,
|
|
can be accessed via the following procedure:
|
|
.Bd -literal -offset indent
|
|
int
|
|
get_ifmib_general(int row, struct ifmibdata *ifmd)
|
|
{
|
|
int name[6];
|
|
size_t len;
|
|
|
|
name[0] = CTL_NET;
|
|
name[1] = PF_LINK;
|
|
name[2] = NETLINK_GENERIC;
|
|
name[3] = IFMIB_IFDATA;
|
|
name[4] = row;
|
|
name[5] = IFDATA_GENERAL;
|
|
|
|
len = sizeof(*ifmd);
|
|
|
|
return sysctl(name, 6, ifmd, &len, (void *)0, 0);
|
|
}
|
|
.Ed
|
|
.Pp
|
|
The fields in
|
|
.Li struct ifmibdata
|
|
are as follows:
|
|
.Bl -tag -width "ifmd_snd_drops"
|
|
.It Li ifmd_name
|
|
.Pq Li "char []"
|
|
the name of the interface, including the unit number
|
|
.It Li ifmd_pcount
|
|
.Pq Li int
|
|
the number of promiscuous listeners
|
|
.It Li ifmd_flags
|
|
.Pq Li int
|
|
the interface's flags (defined in
|
|
.In net/if.h )
|
|
.It Li ifmd_snd_len
|
|
.Pq Li int
|
|
the current instantaneous length of the send queue
|
|
.It Li ifmd_snd_drops
|
|
.Pq Li int
|
|
the number of packets dropped at this interface because the send queue
|
|
was full
|
|
.It Li ifmd_data
|
|
.Pq Li struct if_data
|
|
more information from a structure defined in
|
|
.In net/if.h
|
|
(see
|
|
.Xr if_data 9 )
|
|
.El
|
|
.Pp
|
|
Class-specific information can be retrieved by examining the
|
|
.Dv IFDATA_LINKSPECIFIC
|
|
column instead.
|
|
Note that the form and length of the structure will
|
|
depend on the class of interface.
|
|
For
|
|
.Dv IFT_ETHER ,
|
|
.Dv IFT_ISO88023 ,
|
|
and
|
|
.Dv IFT_STARLAN
|
|
interfaces, the structure is called
|
|
.Dq Li struct ifmib_iso_8802_3
|
|
(defined in
|
|
.In net/if_mib.h ) ,
|
|
and implements a superset of the
|
|
.Tn "RFC 1650"
|
|
MIB for Ethernet-like networks.
|
|
.Sh SEE ALSO
|
|
.Xr sysctl 3 ,
|
|
.Xr intro 4 ,
|
|
.Xr ifnet 9
|
|
.\" .Xr ethermib 4 ,
|
|
.Rs
|
|
.%T "Definitions of Managed Objects for the Ethernet-like Interface Types Using SMIv2"
|
|
.%A F. Kastenholz
|
|
.%D August 1994
|
|
.%O RFC 1650
|
|
.Re
|
|
.Sh HISTORY
|
|
The
|
|
.Nm
|
|
interface first appeared in
|
|
.Fx 2.2 .
|
|
.Sh BUGS
|
|
Many Ethernet-like interfaces do not yet support the Ethernet MIB;
|
|
the interfaces known to support it include
|
|
.Xr ed 4
|
|
and
|
|
.Xr de 4 .
|
|
Regardless, all interfaces automatically support the generic MIB.
|