Packets are dropped in hardware – Brocade Network OS Administrator’s Guide v4.1.1 User Manual
Page 689
VCS Fabric license
Feature name:VCS_FABRIC
2. If the FCoE or DPOD license appears in the show license command output, but the feature does not
work for the expected ports, the probable cause is that the affected ports were not re-enabled after
installing the license.
NOTE
After adding an FCoE or DPOD license, you must disable and re-enable all affected ports. The VCS
Fabric license does not require re-enabling.
You can disable and then enable each affected port, or you can enter the chassis disable command
followed by the chassis enable command to re-enable the entire chassis.
switch# chassis disable
switch# chassis enable
3. If the license does not appear in the show license command output, then it was not installed. In
privileged EXEC mode, enter the license add lictstr command to install the license. For FCoE and
DPOD licenses, you must also disable and enable the switch or port.
switch# license add licstr "*B
slSETgzTgeVGUDeQR4WIfRx7mmXODdSwENoRGEnAmX3Ca3uHeZgXK0b,jzxyzfzKLrMsPN8ClSxvDQRRT8V
yuULyyKTO0ryU6qm4s1jjiSAeV,COoedzCx1v6ycQgnYMeSVp#"
License Added [*B
slSETgzTgeVGUDeQR4WIfRx7mmXODdSwENoRGEnAmX3Ca3uHeZgXK0b,jzxyzfzKLrMsPN8ClSxvDQRRT8V
yuULyyKTO0ryU6qm4s1jjiSAeV,COoedzCx1v6ycQgnYMeSVp# ]
For license change to take effect, please disable/enable port or switch...
switch# chassis disable
switch# chassis enable
Packets are dropped in hardware
This section discusses how to troubleshoot problems in which loss of packets occurs in all traffic, on
specific traffic flows, in specific types of traffic, consistently, or intermittently. Dropped packets could
occur for many reasons, including the following:
• High latency in an end device. Refer to
Verifying packets dropped because of high-latency end
on page 689.
• Broken data path. Refer to
on page 691.
• Noise on an optical line caused by too many CRC errors, packet errors, or NIC interoperability errors.
Checking for noise on an optical line
on page 693.
Verifying packets dropped because of high-latency end device
Packets can sometimes be dropped because of buffer overrun within the fabric caused by end devices
taking longer to respond than expected. For example, an overloaded disk array can cause such latency,
as can a host that does not process data as quickly as expected. Devices that stop receiving data for an
extended period of time can cause excessive latency.
The ultimate solution to these problems is to fix the end device itself. However, some adjustments to the
switch and fabric configuration can help to reduce the problem.
To detect and relieve congestion and dropped packets resulting from latency in end devices, complete
the following steps:
1. Enter the show lldp neighbors detail command to check under "DCBX TLVs" that the end device is
DCB-ready and confirm that the end device is also advertising its DCB capabilities.
switch# show lldp neighbors detail
Neighbors for Interface Te 66/0/55
MANDATORY TLVs
===============
Local Interface: Te 66/0/55 (Local Interface MAC: 0005.3367.26d3)
Remote Interface: port1 (Remote Interface MAC: 0005.1e78.f004)
Packets are dropped in hardware
Network OS Administrator’s Guide
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