diff options
| -rw-r--r-- | share/man/man4/Makefile | 6 | ||||
| -rw-r--r-- | share/man/man4/vlan.4 | 99 |
2 files changed, 102 insertions, 3 deletions
diff --git a/share/man/man4/Makefile b/share/man/man4/Makefile index a3cfbc17194..bf33d94147d 100644 --- a/share/man/man4/Makefile +++ b/share/man/man4/Makefile @@ -1,4 +1,4 @@ -# $OpenBSD: Makefile,v 1.113 2000/04/17 21:38:34 mickey Exp $ +# $OpenBSD: Makefile,v 1.114 2000/04/26 19:00:57 chris Exp $ # $NetBSD: Makefile,v 1.22.4.2 1996/07/18 00:51:10 jtc Exp $ MAN= ac97.4 an.4 atalk.4 atapiscsi.4 audio.4 adv.4 ahc.4 aue.4 bpf.4 \ @@ -17,8 +17,8 @@ MAN= ac97.4 an.4 atalk.4 atapiscsi.4 audio.4 adv.4 ahc.4 aue.4 bpf.4 \ sis.4 sk.4 sl.4 sm.4 spp.4 sppp.4 sqphy.4 ss.4 st.4 ste.4 sv.4 tb.4 \ tcp.4 termios.4 ti.4 tl.4 tlphy.4 tp.4 tqphy.4 tty.4 tun.4 tx.4 \ txphy.4 uaudio.4 udp.4 ugen.4 uhci.4 uhid.4 uk.4 ukphy.4 ulpt.4 \ - umass.4 unix.4 urio.4 usb.4 vnd.4 vr.4 wb.4 wd.4 we.4 wx.4 xl.4 ym.4 \ - zero.4 + umass.4 unix.4 urio.4 usb.4 vlan.4 vnd.4 vr.4 wb.4 wd.4 we.4 wx.4 xl.4 \ + ym.4 zero.4 # IPv6 MAN+= faith.4 gif.4 icmp6.4 inet6.4 ip6.4 diff --git a/share/man/man4/vlan.4 b/share/man/man4/vlan.4 new file mode 100644 index 00000000000..be3be312c56 --- /dev/null +++ b/share/man/man4/vlan.4 @@ -0,0 +1,99 @@ +.\" $OpenBSD: vlan.4,v 1.1 2000/04/26 19:00:57 chris Exp $ +.\" +.Dd 09 January 2000 +.Dt VLAN 4 +.Os +.Sh NAME +.Nm vlan +.Nd "IEEE 802.1Q encapsulation/decapsulation pseudo-device" +.Sh SYNOPSIS +.Cd pseudo-device vlan Op Ar count +.Sh DESCRIPTION +The +.Nm vlan +ethernet interface allows construction of virtual LANs when used in +conjunction with IEEE 802.1Q-compliant ethernet devices. +.Pp +This driver currently supports the following modes of operation: +.Bl -tag -width abc +.It 802.1Q encapsulation over ethernet (Ethernet protocol 0x8100) +Frame headers which normally contain the destination host, source host, and +protocol, are altered with additional information. After the source host, +a 32-bit 802.1Q header is included, with 16 bits for the ether type (0x8100), 3 +bits for the priority field (not used in this implementation), 1 bit for +the canonical field (always 0), and 12 bits for the vlan identifier. Following +the vlan header is the actual ether type for the packet and length information. +.Pp +The 802.1Q header specifies the virtual LAN +and thus allows an ethernet switch or other 802.1Q compliant +network devices to be aware of which device the packet was intended for. +This driver allows OpenBSD to group packets logically with separate +interfaces. +.El +.Pp +The network interfaces are named +.Sy vlan Ns Ar 0 , +.Sy vlan Ns Ar 1 , +etc. +The number of interfaces is given by the corresponding +.Sy pseudo-device +line in the system config file. +.Xr vlan 4 +interfaces support the following unique +.Xr ioctl 2 Ns s : +.Bl -tag -width aaa +.It SIOCSETVLAN: +Set the vlan tag and parent for a given vlan interface. +.It SIOCGETVLAN: +Get the vlan tag and parent for a given vlan interface. +.Pp +.El +The operation mode can be given as +.Bl -tag -width bbb +.It link0 +The parent interface supports VLAN tagging/untagging in hardware, +this requires support from the ethernet driver as well. +.El +.Pp +to +.Xr ifconfig 8 . +.Pp +.Sh SEE ALSO +.Xr netintro 4 , +.Xr ip 4 , +.Xr bridge 4 , +.Xr inet 4 , +.Xr ifconfig 8 +.Pp +A draft of IEEE 802.1Q standard can be obtained from +http://grouper.ieee.org/groups/802/1/pages/802.1Q.html +or the final version can be purchased from the +Institute of Electrical and Electronic Engineers, Inc. +.Sh BUGS +The 802.1Q specification allows for operation over FDDI and Token Ring +as well as Ethernet. +This driver only supports such operation with ethernet devices. +.Pp +Some ethernet chips (notably the Intel 82558/82559) automatically +discard frames that are larger then 1500 bytes. All ethernet +chips sporting this feature should allow for it to be turned off. +Optimally, upon loading, the chip's OpenBSD driver would do this. +A temporary kludge is to set the MTU for each machine behind each VLAN to +1496 or less. Refer to the hardware manual for your ethernet chip to determine +if it has this feature, and if so, for information on how to turn it off. +A symptom of this problem is that small packets (ICMP) +but packets which are >MTU size are dropped, thus causing +bulk TCP transfers to hang. +.Pp +Some ethernet chips support 802.1Q tagging/untagging in hardware, but +do not have the appropriate hooks in their driver to pass the packet +directly to if_vlan. The PCI device driver if_ti is able to do this, +use it as a reference. +.Pp +This driver could be extended to support the Cisco ISL VLAN protocol, +detailed at http://www.cisco.com/warp/public/741/4.html. Unfortunately, +public reimplementation of this protocol is currently prevented by patent +(at least in the USA). +.Pp +.Sh AUTHOR +Originally wollman@freebsd.org |