lldptool(8) Linux lldptool(8)NAME
evb22 - Show / manipulate EVB IEEE 802.1 Ratified Standard TLV configu‐
ration
SYNOPSIS
lldptool -t -i ethx -g ncb -V evb
lldptool -t -i ethx -g ncb -V evb -c evbmode
lldptool -T -i ethx -g ncb -V evb -c enabletx=[yes|no]
lldptool -T -i ethx -g ncb -V evb -c evbmode=[bridge|station]
lldptool -t -i ethx -g ncb -V evb -c evbrrreq
lldptool -T -i ethx -g ncb -V evb -c evbrrreq=[yes|no]
lldptool -t -i ethx -g ncb -V evb -c evbrrcap
lldptool -T -i ethx -g ncb -V evb -c evbrrcap=[yes|no]
lldptool -t -i ethx -g ncb -V evb -c evbgpid
lldptool -T -i ethx -g ncb -V evb -c evbgpid=[yes|no]
lldptool -t -i ethx -g ncb -V evb -c ecpretries
lldptool -T -i ethx -g ncb -V evb -c ecpretries=[0..7]
lldptool -t -i ethx -g ncb -V evb -c ecprte
lldptool -T -i ethx -g ncb -V evb -c ecprte=[0..31]
lldptool -t -i ethx -g ncb -V evb -c vdprwd
lldptool -T -i ethx -g ncb -V evb -c vdprwd=[0..31]
lldptool -t -i ethx -g ncb -V evb -c vdprka
lldptool -T -i ethx -g ncb -V evb -c vdprka=[0..31]
DESCRIPTION
The Edge Virtual Bridge (EVB) TLV is a TLV to announce the station and
bridge's edge virtual bridging (EVB) capabilities and may request the
bridge port to be set into reflective relay (hairpin) mode. If both
sides agree on the modes and time out values, the edge control protocol
(ECP) will be used to exchange VSI discovery protocol (VDP) data using
ECP frames between the host interface and the adjacent switch port fac‐
ing the host interface.
This man pages describes the IEEE 802.1 Qbg ratified standard dated
from July 5th, 2012. The arguments and parameters differ from the IEEE
802.1 Qbg draft 0.2, which is also implemented. The EVB protocol ver‐
sion to be used depends on the organizational unique identifier (OUI)
of the EVB TLV in the LLDP data stream. A OUI value of 0x001b3f stands
for the IEEE 802.1 Qbg draft 0.2, a OUI value of 0x0080c2 stands for
the IEEE 802.1 Qbg ratified standard. The version of the ECP and VDP
protocols are determined by the ethernet type field in the ethernet
header. The ethernet type value for IEEE 802.1 Qbg draft 0.2 is
0x88b7, the value for IEEE 802.1 Qbg ratified standard is 0x8890. Note
that the EVB protocol is exchanged between nearest customer bridges
only, employing the reserved multicast MAC address 01:80:c2:00:00:00 as
destination MAC address. lldpad(8) supports both versions, the switch
port configuration determines which version will be used. The switch
port configuration should select only one protocol version, never both.
The command line options and arugments are explained in the lldptool(8)
man pages. Only the EVB, ECP and VDP protocol specific parameters are
detailed in this manual page.
ARGUMENTS
The invocation without command line option '-c' and argument displays
the complete EVB, ECP and VDP protocol settings. See below for a
detailed description on how to interpret the output.
-c text
Use command line option '-c' and one of the following arguments
to display and set individual parameters. Text can be one of
the following values:
enabletx
Enables or disables the EVB TLV to be transmitted. When set to
disabled no EVB TLV will be included in the LLDP data stream.
Furthermore the output of the complete EVB settings without
option '-c' will be empty.
evbmode
Display the current role or sets the role the to given value.
Supported values are either "station" or "bridge".
evbrrreq
Shows the current reflective relay (hairpin) request mode or
sets the reflective relay (hairpin) request mode. If the value
is "yes", the station requests the interface facing switch port
to be set in reflective relay (hairpin) mode. This field is
only valid for stations, the output of evbmode equals "station".
evbrrcap
Shows the current reflective relay (hairpin) capabilities or
sets the reflective relay (hairpin) capabilities. If the value
is "yes", the switch port will be set in reflective relay (hair‐
pin) mode. This field is only valid for switches, the output of
evbmode equals "bridge".
gpid Shows the current station or switch support for grouping or
turns on/off the station or switch support for grouping. If set
to true, the station or switch wants to use group identifiers in
VDP protocols.
ecpretries
Shows or sets the maximum number of retries for ECP frames to be
retransmitted. A retransmit occurs when no ECP acknowledgement
message has been received during a given time period.
ecprte Shows or sets the local run time exponent (RTE). The RTE will
be used as the base for the timing of the ECP protocol time outs
and retransmits. The wait time is calcuated as 10*2ecprte micro
seconds.
vdprwd Shows or sets the number of resource wait delay value. This
value is calcuated as 10*2vdprwd micro seconds and determines
the maximum wait time for VDP protocol acknowledgements.
vdprka Shows or sets the number of re-init keep alive value. This
value is calcuated as 10*2vdprka micro seconds and determines
the wait time for VDP protocol to send a keep alive message.
Theory of Operation
The EVB TLV is used to announce and exchange supported parameters
between the station and an adjacent switch. If reflectiverelay is
active, the switch sends back ethernet frames on the very same port it
received the frame on. This is an extension to the current bridging
standard and allows communication between virtual machines on the same
host through the switch port.
EXAMPLE & USAGE
Display locally configured values for eth0
lldptool -t -g ncb -i eth0 -V evb
EVB Configuration TLV
bridge:(00)
station:rrreq,rrstat(0x5)
retries:7 rte:31
mode:station r/l:0 rwd:31
r/l:0 rka:8
This output is displayed when enabletx has been enabled. The
first line shows the currently known status of the bridge. The
second line shows the currently known status of the station.
The status is displayed verbose appended by the hexadecimal
value in parenthesis. The verbose output uses the bit naming
convention used in the standard document. The third line dis‐
plays the values for the ECP protocol number of retransmits
(retries) and the retransmit timeout exponent. The forth line
shows the current mode of operation, either bridge or station,
the resource wait delay value (rwd) and an indication if the
local (0) or remote (1) rwd value is used. The fifth line dis‐
plays the value of the re-init keep alive counter (rka) and an
indication if the local (0) or remote (1) rka value is used.
Display the currently requested forwarding mode for eth0
lldptool -t -g ncb -i eth0 -V evb -c evbrrreq
Display the locally configured value for RTE
lldptool -t -g ncb -i eth0 -V evb -c evbrte
Set the value for RTE to its maximum value
lldptool -T -g ncb -i eth0 -V evb -c rte=7
Set the value for enabletx to yes to transmit EVB TLV
to the switch. lldptool -T -g ncb -i eth0 -V evb -c
enabletx=yes
NOTES
Currently the code in lldpad reflects IEEE 802.1 Qbg draft 0.2 of the
upcoming standard. Wireshark support for IEEE 802.1 Qbg ratified stan‐
dard TLVs is currently missing. Support for the IEEE 802.1 Qbg rati‐
fied standard protocols ECP and VDP is currently under development and
not fully functional.
SEE ALSOlldptool-vdp(8), lldptool(8), lldpad(8)
IEEE 802.1Qbg (http://www.ieee802.org/1/pages/802.1bg.html)
AUTHOR
Thomas Richter
open-lldp February 2013 lldptool(8)
