Release Notes for Cisco Catalyst Blade Switch 3120 for HP, Cisco IOS Release 12.2(50)SE and Later

OL-18270-03

Limitations and Restrictions

Routing

These are the routing limitations:

• The switch stack might reload if the switch runs with this configuration for several hours, depleting

the switch memory and causing the switch to fail:

–

The switch has 400 Open Shortest Path First (OSPF) neighbors.

–

The switch has thousands of OSPF routes.

The workaround is to reduce the number of OSPF neighbors to 200 or less. (CSCse65252)

• When the PBR is enabled and QoS is enabled with DSCP settings, the CPU utilization might be high

if traffic is sent to unknown destinations.

The workaround is to not send traffic to unknown destinations. (CSCse97660)

SPAN and RSPAN

These are the SPAN and Remote SPAN (RSPAN) limitations.

• When egress SPAN is running on a 10-Gigabit Ethernet port, only about 12 percent of the egress

traffic is monitored.

There is no workaround. This is a hardware limitation. (CSCei10129)

• When the logging event-spanning-tree interface configuration command is configured and logging

to the console is enabled, a topology change might generate a large number of logging messages,

causing high CPU utilization. CPU utilization can increase with the number of spanning-tree

instances and the 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 (CSCsg91027):

–

Disable logging to the console.

–

Rate-limit logging messages to the console.

–

Remove the logging event spanning-tree interface configuration command from the interfaces.

• The far-end fault optional facility is not supported on the GLC-GE-100FX SFP module.

The workaround is to configure aggressive UDLD. (CSCsh70244).

VLANs

This is a VLAN limitation:

When the domain is authorized in the guest VLAN on a member switch port without link loss and an

Extensible Authentication Protocol over LAN (EAPOL) is sent to an IEEE 802.1x supplicant to

authenticate, the authentication fails. This problem happens intermittently with certain stacking

configurations and only occurs on the member switches.

The workaround is to enter the shut and no shut interface configuration commands on the port to reset

the authentication status. (CSCsf98557)