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				.\"
				.\" Copyright (c) 2025 Mateusz Piotrowski <0mp@FreeBSD.org>
				.\"
				.\" SPDX-License-Identifier: BSD-2-Clause
				.\"
				.Dd November 13, 2025
				.Dt DTRACE_MIB 4
				.Os
				.Sh NAME
				.Nm dtrace_mib
				.Nd a DTrace provider for Management Information Base
				.Sh SYNOPSIS
				.Cm mib: Ns Ar module Ns Cm \&:count: Ns Ar name
				.Pp
				In
				.Xr config 5 :
				.Cd "options KDTRACE_MIB_SDT"
				.Sh DESCRIPTION
				The
				.Nm mib
				provider allows tracing of Management Information Base stats counters.
				.Pp
				The list of instrumented
				.Ar module Ns s
				includes:
				.Bl -tag -offset indent -width ipcomp -compact
				.It Cm ah
				IP Authentication Header (RFC 2402),
				.Xr ipsec 4
				.It Cm esp
				IP Encapsulating Security Payload (RFC 1827, RFC 2406),
				.Xr ipsec 4
				.It Cm icmp
				.Xr icmp 4
				.It Cm icmp6
				.Xr icmp6 4
				.It Cm ip
				.Xr ip 4
				.It Cm ip6
				.Xr ip6 4
				.It Cm ipcomp
				IP Payload Compression Protocol,
				.Xr ipsec 4
				.It Cm ipsec
				.Xr ipsec 4
				.It Cm tcp
				.Xr tcp 4
				.It Cm udp
				.Xr udp 4
				.El
				.Pp
				The
				.Cm mib: Ns Ar module Ns Cm \&:count: Ns Ar name
				probes fire when the
				.Ar name
				counter in
				.Ar modules
				increases.
				.Pp
				The first probe argument,
				.Vt uint64_t Va arg0 ,
				represents the value that the
				.Ar name
				counter will increase by.
				.Pp
				Note that some probes like
				.Cm mib:esp:count:esps_hist
				or
				.Cm mib:icmp6:count:icp6s_outhist
				provide other arguments as well.
				.Sh EXAMPLES
				.Ss Example 1 : Tracing IP Stats Counters
				When debugging network issues one common clue is an unexpectedly
				incrementing error counter.
				This is helpful, in that it gives us an
				idea of what might be going wrong, but often these counters may be
				incremented in different functions.
				.Pp
				Trace all
				.Nm mib
				probes in the
				.Xr ip 4
				module and print the current count and a stack trace:
				.Pp
				.Bd -literal -offset 2n
				# dtrace -n 'mib:ip:count: { printf("%d", arg0); stack(); }'
				dtrace: description 'mib:ip:count: ' matched 29 probes
				CPU ID FUNCTION:NAME
				7 98784 count:ips_localout 1
				kernel`ip_output+0x17a2
				kernel`udp_send+0xaca
				kernel`sosend_dgram+0x315
				kernel`sousrsend+0x79
				kernel`kern_sendit+0x1be
				kernel`sendit+0x1ab
				kernel`sys_sendmsg+0x5b
				kernel`amd64_syscall+0x169
				kernel`0xffffffff81094b8b
				.Ed
				.Sh SEE ALSO
				.Xr dtrace 1 ,
				.Xr dtrace_ip 4 ,
				.Xr dtrace_tcp 4 ,
				.Xr dtrace_udp 4 ,
				.Xr tracing 7 ,
				.Xr sysctl 8
				.Rs
				.%B The illumos Dynamic Tracing Guide
				.%O Chapter mib Provider
				.%D 2008
				.%U https://illumos.org/books/dtrace/chp-mib.html
				.Re
				.Sh AUTHORS
				.An -nosplit
				The
				.Nm mib
				provider was added to
				.Fx
				by
				.An Kristof Provost Aq Mt kp@FreeBSD.org .
				.Pp
				This manual page was written by
				.An Mateusz Piotrowski Aq Mt 0mp@FreeBSD.org .
				.Sh CAVEATS
				The
				.Nm mib
				provider probes are not a stable interface.
				Use the untyped
				.Va arg0 , ... , arg9
				variables to access probe arguments
				instead of the
				.Va args[]
				array.