Brocade Communications Systems SN3000B Command Reference Manual page 690

22
portCfgLongDistance
distance_level
vc_translation_link_init
desired_distance
EXAMPLES
To configure a switch port 63 to support a 100 km link and be initialized using the long distance link
initialization protocol:
664
Specify the long distance level as one of the following (the numerical value
representing each distance_level is shown in parentheses):
L0 (0)
Specify L0 to configure the port as a regular port. A total of 20 full-size frame
buffers are reserved for data traffic, regardless of the port's operating speed;
therefore, the maximum supported link distance is up to 5 km at 2 Gbps, up to 2
km at 4 Gbps and up to 1 km at 8, 10, and 16 Gbps.
LE (3)
Specify LE mode to configure an E_Ports distance greater than 5 km and up to 10
km. A total of 5, 10, 20, 40, 50, and 80 full-size frame buffers are reserved for data
traffic at port speeds of 1 Gbps, 2 Gbps, 4 Gbps, 8, 10, and 16 Gbps. LE does not
require an Extended Fabrics license. If a port in LE mode is set to autonegotiation,
it will reserve the buffers for the highest support speed on that port. If this is not
the desired buffer allocation, you should set the port to a fixed speed.
LD (5)
Specify LD for automatic long-distance configuration. The buffer credits for the
given E_Port are automatically configured based on the actual link distance. Up to
a total of 1452 full-size frame buffers are reserved depending on the distance
measured during E_Port initialization. If a value for desired_distance is specified,
it is used as the upper limit to the measured distance. If a port in LD mode is set to
autonegotiation, it will reserve the buffers for the highest support speed on that
port. If this is not the desired buffer allocation, you should set the port to a fixed
speed.
LS (6)
Specify LS mode to configure a static long distance link with a fixed buffer
allocation greater than 10 km. Up to a total of 1452 full-size frame buffers are
reserved for data traffic, depending on the specified desired_distance value. If a
port in LS mode is set to autonegotiation, it will reserve the buffers for the highest
support speed on that port. If this is not the desired buffer allocation, you should
set the port to a fixed speed.
Specifies the fill words used on long distance links. When set to 1, the link uses
ARB fill words (default). When set to 0, the link uses IDLE fill words. The IDLE fill
word option is not compatible with QoS configured links and Credit Recovery
enabled links. You must disable these features before configuring long distance
IDLE fill words.
This parameter is required when a port is configured as an LD or an LS mode link.
In LD mode, the value of desired_distance is the upper limit of the link distance
and is used to calculate buffer availability for other ports in the same port group.
When the measured distance exceeds the value of desired_distance, this value is
used to allocate the buffers. In this case, the port operates in degraded mode
instead of being disabled due to insufficient buffers. In LS mode, the actual link
distance is not measured, instead the desired_distance is used to allocate the
buffers required for the port.
switch:admin> portcfglongdistance 4/15 LS 1 100
switch:admin> portshow 4/15
portCFlags: 0x1
portFlags: 0x20001
portType: 1.1
PRESENT LED
Fabric OS Command Reference
53-1001764-01