Brocade FastIron Ethernet Switch Platform and Layer 2 Switching Configuration Guide - Manual (Page 65)

Viewing the status of LFS-enabled links
The status of an LFS-enabled link is shown in the output of the show interface and show interface
brief commands, as shown in the following examples.
device#show interface e 10/1
10GigabitEthernet10/1 is down (remote fault), line protocol is down
Hardware is 10GigabitEthernet, address is 0000.0027.79d8 (bia 0000.0027.79d8)
Configured speed 10Gbit, actual unknown, configured duplex fdx, actual unknown
Member of L2 VLAN ID 1, port is untagged, port state is BLOCKING
BPDU guard is Disabled, ROOT protect is Disabled
Link Fault Signaling is Enabled, Link Error Dampening is Disabled
STP configured to ON, priority is level0
Flow Control is disabled
mirror disabled, monitor disabled
Truncated for brevity...
The bold text in the above output shows that the LFS-enabled link (port 10/1) is down because of an
error on the remote port, as indicated by remote fault .
Syntax: show interface ethernet port
device#show interfaces brief
Port Link State Dupl Speed Trunk Tag Pvid Pri MAC Name
10/1 Err-LFS
None None None None No 1 0 0000.0027.79d8
The bold text in the above output indicates that there is an error on the LFS-enabled link on port 10/1
and the link is down.
Syntax: show interfaces brief
Jumbo frame support
Ethernet traffic moves in units called frames. The maximum size of frames is called the Maximum
Transmission Unit (MTU). When a network device receives a frame larger than its MTU, the data is
either fragmented or dropped. Historically, Ethernet has a maximum frame size of 1500 bytes, so most
devices use 1500 as their default MTU.
Jumbo frames are Ethernet frames with more than 1,500 bytes MTU. Conventionally, jumbo frames can
carry up to 10200 bytes MTU. Brocade FastIron devices support Layer 2 jumbo frames on 10/100,
100/100/1000, and 10GbE ports.
Brocade ICX 6650 devices support Layer 2 jumbo frames on 10/100, 100/100/1000, 40GbE and 10GbE
ports. Conventionally, jumbo frames can carry up to 9,000 bytes MTU. In cut-through mode, in jumbo
mode, the MTU is 10200 which uses 20 buffers. In non-jumbo mode MTU is 1522 which uses 3 buffers.
Packet InError Detection
Packet InError Detection identifies links that receive more number of bad frames than configured
threshold and disables them to avoid instability in the network. For instance, if a network has redundant
uplinks, usually only one link is in forwarding state and the rest are redundant and blocked. If one of the
redundant links becomes faulty, it may drop the PDUs and become a forwarding link. This can cause
loops in the network. Packet InError Detection detects the faults in the link and disables the link to
prevent loops in the network.
Viewing the status of LFS-enabled links
FastIron Ethernet Switch Platform and Layer 2 Switching Configuration Guide 65
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