Enabling Auto-Negotiation Maximum Port Speed Advertisement And Down-Shift - Brocade Communications Systems FastIron Administration Manual

NOTE
On FastIron devices, when setting the speed and duplex-mode of an interface to 1000-full, configure
one side of the link as master (1000-full-master) and the other side as slave (1000-full-slave).
NOTE
On Brocade ICX 6610 and ICX 6650 devices, after you remove the 10 Gbps speed from the running
configuration, plugging in a 1Gbps optic SFP transceiver into a 10 Gbps port causes the software to fail
to revert the ports back from the default 10Gbps mode to the 1 Gbps speed. Remove the 1Gbps SFP
transceiver and plug in the 10Gbps optic SFP+transceiver so that the devices go into the default 10
Gbps mode.
NOTE
When you use fixed speed and duplex configuration, you should use the non-auto MDI-MDIX
configuration.
Configuration considerations for port speed and duplex mode
The following considerations apply to the port speed and duplex mode configuration:
• When a local partner issues a speed-duplex 100-full or speed-duplex 10-full command, if the
remote partner does not issue the same commands, it becomes 100-half or 10-half, and may
receive collision errors. The local partner may receive In Errors such as CRC, fragments, or bad
packets.
• When a local partner issues a speed-duplex 100-full or speed-duplex 10-full command, if the
remote partner issues the same command, the port may or may not come up because both sides
enter the force mode and want to force the partner to accept these conditions. If both sides come up,
they may not receive any In or Out Errors.
• When both local and remote partners have a force mode configuration such as 100-full/half or 10-
full/half, for example, ICX6610-24F 1/1/1 (local link 100-full)<->(100-full remote link) FCX 1/1/1, if
another force mode such as 10-full is entered in a local or remote partner, the remote or local partner
link may or may not come up. This is an IEEE force mode standard. To resolve the force mode
changing, it is recommended that you first change to auto mode on one side, before switching to
another force mode configuration.
Enabling auto-negotiation maximum port speed advertisement and
down-shift
NOTE
For optimal link operation, link ports on devices that do not support 802.3u must be configured with like
parameters, such as speed (10,100,1000), duplex (half, full), MDI/MDIX, and Flow Control.
Maximum Port speed advertisement is an enhancement to the auto-negotiation feature, a mechanism
for accommodating multi-speed network devices by automatically configuring the highest performance
mode of inter-operation between two connected devices.
Port speed down-shift enables Gbps copper ports on the Brocade device to establish a link at 1000.
Mbps over a 4-pair wire when possible, or to down-shift to 100 Mbps if the medium is a 2-pair wire.
Maximum port speed advertisement enables you to configure an auto-negotiation maximum speed that
Gbps copper ports on the Brocade device will advertise to the connected device. You can configure a
FastIron Ethernet Switch Administration Guide
53-1003625-01

Enabling auto-negotiation maximum port speed advertisement and down-shift

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