1.\" $NetBSD: brconfig.8,v 1.13 2006/01/12 21:49:11 wiz Exp $ 2.\" 3.\" Copyright 2001 Wasabi Systems, Inc. 4.\" All rights reserved. 5.\" 6.\" Written by Jason R. Thorpe for Wasabi Systems, Inc. 7.\" 8.\" Redistribution and use in source and binary forms, with or without 9.\" modification, are permitted provided that the following conditions 10.\" are met: 11.\" 1. Redistributions of source code must retain the above copyright 12.\" notice, this list of conditions and the following disclaimer. 13.\" 2. Redistributions in binary form must reproduce the above copyright 14.\" notice, this list of conditions and the following disclaimer in the 15.\" documentation and/or other materials provided with the distribution. 16.\" 3. All advertising materials mentioning features or use of this software 17.\" must display the following acknowledgement: 18.\" This product includes software developed for the NetBSD Project by 19.\" Wasabi Systems, Inc. 20.\" 4. The name of Wasabi Systems, Inc. may not be used to endorse 21.\" or promote products derived from this software without specific prior 22.\" written permission. 23.\" 24.\" THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND 25.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 26.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 27.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL WASABI SYSTEMS, INC 28.\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 29.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 30.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 31.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 32.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 33.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 34.\" POSSIBILITY OF SUCH DAMAGE. 35.\" 36.Dd March 19, 2003 37.Dt BRCONFIG 8 38.Os 39.Sh NAME 40.Nm brconfig 41.Nd configure network bridge parameters 42.Sh SYNOPSIS 43.Nm 44.Fl a 45.Nm 46.Ar bridge 47.Nm 48.Ar bridge 49.Ar command 50.Op Ar args ... 51.Sh DESCRIPTION 52The 53.Nm 54utility is used to configure network bridge parameters and retrieve 55network bridge parameters and status from the kernel. 56The bridging function is implemented by the 57.Xr bridge 4 58driver. 59.Pp 60A network bridge creates a logical link between two or more 61IEEE 802 networks that use the same (or 62.Dq similar enough ) 63framing format. 64For example, it is possible to bridge Ethernet 65and 802.11 networks together, but it is not possible to bridge 66Ethernet and Token Ring together. 67.Pp 68Bridge interfaces are created using the 69.Xr ifconfig 8 70command's 71.Dq create 72sub-command. 73All other bridge configuration is performed using 74.Nm . 75.Pp 76The options are as follows: 77.Bl -tag -width indent 78.It Fl a 79Display the status of all bridge devices present on the system. 80This flag is mutually exclusive with all other sub-commands. 81.El 82.Pp 83All other operations require that a bridge be specified. 84If a bridge is specified with no sub-commands, 85the status of that bridge is displayed. 86The following sub-commands are available: 87.Pp 88.Bl -tag -width indent 89.It Cm up 90Start forwarding packets on the bridge. 91.It Cm down 92Stop forwarding packets on the bridge. 93.It Cm add Ar interface 94Add the interface named by 95.Ar interface 96as a member of the bridge. 97The interface is put into promiscuous mode 98so that it can receive every packet sent on the network. 99.It Cm delete Ar interface 100Remove the interface named by 101.Ar interface 102from the bridge. 103Promiscuous mode is disabled on the interface when 104it is removed from the bridge. 105.It Cm maxaddr Ar size 106Set the size of the bridge address cache to 107.Ar size . 108The default is 100 entries. 109.It Cm timeout Ar seconds 110Set the timeout of address cache entries to 111.Ar seconds 112seconds. 113If 114.Ar seconds 115is zero, then address cache entries will not be expired. 116The default is 240 seconds. 117.It Cm deladdr Ar address 118Delete 119.Ar address 120from the address cache. 121.It Cm flush 122Delete all dynamically-learned addresses from the address cache. 123.It Cm flushall 124Delete all addresses, including static addresses, from the address cache. 125.It Cm discover Ar interface 126Mark an interface as a 127.Dq discovering 128interface. 129When the bridge has no address cache entry 130(either dynamic or static) 131for the destination address of a packet, 132the bridge will forward the packet to all 133member interfaces marked as 134.Dq discovering . 135This is the default for all interfaces added to a bridge. 136.It Cm -discover Ar interface 137Clear the 138.Dq discovering 139attribute on a member interface. 140For packets without the 141.Dq discovering 142attribute, the only packets forwarded on the interface are broadcast 143or multicast packets and packets for which the destination address 144is known to be on the interface's segment. 145.It Cm ipf 146Enable IPF packet filtering on the bridge. 147The current implementation passes 148all ARP and RARP packets through the bridge while filtering IP and ICMP 149packets through IPF. 150.It Cm -ipf 151Disable IPF packet filtering on the bridge (the default). 152.It Cm learn Ar interface 153Mark an interface as a 154.Dq learning 155interface. 156When a packet arrives on such an interface, the source 157address of the packet is entered into the address cache as being a 158destination address on the interface's segment. 159This is the default for all interfaces added to a bridge. 160.It Cm -learn Ar interface 161Clear the 162.Dq learning 163attribute on a member interface. 164.It Cm stp Ar interface 165Enable Spanning Tree protocol on 166.Ar interface . 167The 168.Xr bridge 4 169driver has support for the IEEE 802.1D Spanning Tree protocol (STP). 170Spanning Tree is used to detect and remove loops in a network topology. 171.It Cm -stp Ar interface 172Disable Spanning Tree protocol on 173.Ar interface . 174This is the default for all interfaces added to a bridge. 175.It Cm maxage Ar seconds 176Set the time that a Spanning Tree protocol configuration is valid. 177The default is 20 seconds. 178The minimum is 1 second and the maximum is 255 seconds. 179.It Cm fwddelay Ar seconds 180Set the time that must pass before an interface begins forwarding 181packets when Spanning Tree is enabled. 182The default is 15 seconds. 183The minimum is 1 second and the maximum is 255 seconds. 184.It Cm hellotime Ar seconds 185Set the time between broadcasting of Spanning Tree protocol 186configuration messages. 187The default is 2 seconds. 188The minimum is 1 second and the maximum is 255 seconds. 189.It Cm priority Ar value 190Set the bridge priority for Spanning Tree. 191The default is 32768. 192The minimum is 0 and the maximum is 65536. 193.It Cm ifpriority Ar interface Ar value 194Set the Spanning Tree priority of 195.Ar interface 196to 197.Ar value . 198The default is 128. 199The minimum is 0 and the maximum is 255. 200.It Cm ifpathcost Ar interface Ar value 201Set the Spanning Tree path cost of 202.Ar interface 203to 204.Ar value . 205The default is 55. 206The minimum is 0 and the maximum is 65535. 207.El 208.Sh EXAMPLES 209The following, when placed in the file 210.Pa /etc/ifconfig.bridge0 , 211will cause a bridge called 212.Sq bridge0 213to be created, add the interfaces 214.Sq ray0 215and 216.Sq fxp0 217to the bridge, and then enable packet forwarding. 218Such a configuration could be used to implement a simple 219802.11-to-Ethernet bridge (assuming the 802.11 interface is 220in ad-hoc mode). 221.Bd -literal -offset indent 222create 223!brconfig $int add ray0 add fxp0 up 224.Ed 225.Pp 226Consider a system with two 4-port Ethernet boards. 227The following placed in the file 228.Pa /etc/ifconfig.bridge0 229will cause a bridge consisting of all 8 ports with Spanning Tree 230enabled to be created: 231.Bd -literal -offset indent 232create 233!brconfig $int \e 234 add tlp0 stp tlp0 \e 235 add tlp1 stp tlp1 \e 236 add tlp2 stp tlp2 \e 237 add tlp3 stp tlp3 \e 238 add tlp4 stp tlp4 \e 239 add tlp5 stp tlp5 \e 240 add tlp6 stp tlp6 \e 241 add tlp7 stp tlp7 \e 242 up 243.Ed 244.Sh SEE ALSO 245.Xr bridge 4 , 246.Xr ifconfig.if 5 , 247.Xr ifconfig 8 , 248.Xr ipf 8 249.Sh HISTORY 250The 251.Nm 252utility first appeared in 253.Nx 1.6 . 254.Sh AUTHORS 255The 256.Xr bridge 4 257driver and 258.Nm 259utility were originally written by 260.An Jason L. Wright 261.Aq jason@thought.net 262as part of an undergraduate independent study at the 263University of North Carolina at Greensboro. 264.Pp 265This version of the 266.Nm 267utility was written from scratch by 268.An Jason R. Thorpe 269.Aq thorpej@wasabisystems.com . 270