.TH DCB-DCBX 8 "13 December 2020" "iproute2" "Linux"
.SH NAME
dcb-dcbx \- show / manipulate port DCBX (Data Center Bridging eXchange)
.SH SYNOPSIS
.sp
.ad l
.in +8

.ti -8
.B dcb
.RI "[ " OPTIONS " ] "
.B dcbx
.RI "{ " COMMAND " | " help " }"
.sp

.ti -8
.B dcb dcbx show dev
.RI DEV

.ti -8
.B dcb dcbx set dev
.RI DEV
.RB "[ " host " ]"
.RB "[ " lld-managed " ]"
.RB "[ " cee " ]"
.RB "[ " ieee " ]"
.RB "[ " static " ]"

.SH DESCRIPTION

Data Center Bridging eXchange (DCBX) is a protocol used by DCB devices to
exchange configuration information with directly connected peers. The Linux DCBX
object is a 1-byte bitfield of flags that configure whether DCBX is implemented
in the device or in the host, and which version of the protocol should be used.
.B dcb dcbx
is used to access the per-port Linux DCBX object.

There are two principal modes of operation: in
.B host
mode, DCBX protocol is implemented by the host LLDP agent, and the DCB
interfaces are used to propagate the negotiate parameters to capable devices. In
.B lld-managed
mode, the configuration is handled by the device, and DCB interfaces are used
for inspection of negotiated parameters, and can also be used to set initial
parameters.

.SH PARAMETERS

When used with
.B dcb dcbx set,
the following keywords enable the corresponding configuration. The keywords that
are not mentioned on the command line are considered disabled. When used with
.B show,
each enabled feature is shown by its corresponding keyword.

.TP
.B host
.TQ
.B lld-managed
The device is in the host mode of operation and, respectively, the lld-managed
mode of operation, as described above. In principle these two keywords are
mutually exclusive, but
.B dcb dcbx
allows setting both and lets the driver handle it as appropriate.

.TP
.B cee
.TQ
.B ieee
The device supports CEE (Converged Enhanced Ethernet) and, respecively, IEEE
version of the DCB specification. Typically only one of these will be set, but
.B dcb dcbx
does not mandate this.

.TP
.B static
indicates the engine supports static configuration. No actual negotiation is
performed, negotiated parameters are always the initial configuration.

.SH EXAMPLE & USAGE

Put the DCB engine into the "host" mode of operation, and use IEEE-standardized
DCB interfaces:

.P
# dcb dcbx set dev eth0 host ieee

Show what was set:

.P
# dcb dcbx show dev eth0
.br
host ieee

.SH EXIT STATUS
Exit status is 0 if command was successful or a positive integer upon failure.

.SH SEE ALSO
.BR dcb (8)

.SH REPORTING BUGS
Report any bugs to the Network Developers mailing list
.B <netdev@vger.kernel.org>
where the development and maintenance is primarily done.
You do not have to be subscribed to the list to send a message there.

.SH AUTHOR
Petr Machata <me@pmachata.org>