Qos" Section; Span And Rspan" Section - Cisco 3020 - Catalyst Blade Switch Release Note

Limitations and Restrictions
number of interfaces configured with the logging event-spanning-tree interface configuration
command. This condition adversely affects how the switch operates and could cause problems such as
STP convergence delay.
High CPU utilization can also occur with other conditions, such as when debug messages are logged at
a high rate to the console.
Use one of these workarounds:
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Remove the logging event spanning-tree interface configuration command from the interfaces.
QoS
These are the quality of service (QoS) limitations:
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SPAN and RSPAN
These are the SPAN and Remote SPAN (RSPAN) limitations.
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Release Notes for the Cisco Catalyst Blade Switch 3020 for HP, Cisco IOS Release 12.2(40)SE1 and Later
10
Disable logging to the console.
Rate-limit logging messages to the console. (CSCsg91027)
Some switch queues are disabled if the buffer size or threshold level is set too low with the mls qos
queue-set output global configuration command. The ratio of buffer size to threshold level should
be greater than 10 to avoid disabling the queue. The workaround is to choose compatible buffer sizes
and threshold levels. (CSCea76893)
When auto-QoS is enabled on the switch, priority queuing is not enabled. Instead, the switch uses
shaped round robin (SRR) as the queuing mechanism. The auto-QoS feature is designed on each
platform based on the feature set and hardware limitations, and the queuing mechanism supported
on each platform might be different. There is no workaround. (CSCee22591)
A QoS service policy with a policy map containing more than 62 policers cannot be added to an
interface by using the service-policy interface configuration command. The workaround is to use
policy maps with 62 or fewer policers. (CSCsc59418)
Egress SPAN routed packets (both unicast and multicast) show the incorrect source MAC address.
For remote SPAN packets, the source MAC address should be the MAC address of the egress VLAN,
but instead the packet shows the MAC address of the RSPAN VLAN. For local SPAN packets with
native encapsulation on the destination port, the packet shows the MAC address of VLAN 1. This
problem does not appear with local SPAN when the encapsulation replicate option is used. This
limitation does not apply to bridged packets. The workaround is to use the encapsulate replicate
keywords in the monitor session global configuration command. Otherwise, there is no
workaround. This is a hardware limitation. (CSCdy81521)
During periods of very high traffic when two RSPAN source sessions are configured, the VLAN ID
of packets in one RSPAN session might overwrite the VLAN ID of the other RSPAN session. If this
occurs, packets intended for one RSPAN VLAN are incorrectly sent to the other RSPAN VLAN.
This problem does not affect RSPAN destination sessions. The workaround is to configure only one
RSPAN source session. This is a hardware limitation. (CSCea72326)
Cisco Discovery Protocol (CDP), VLAN Trunking Protocol (VTP), and Port Aggregation Protocol
(PAgP) packets received from a SPAN source are not sent to the destination interfaces of a local
SPAN session. The workaround is to use the monitor session session_number destination
{interface interface-id encapsulation replicate} global configuration command for local SPAN.
(CSCed24036)
OL-14130-02