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Release Notes for the Cisco IE 2000 Switches, Cisco IOS Release 15.2(1)EY
NEW DOC # PENDING
Important Notes
Spanning Tree Protocol
•
CSCtl60247
When a switch or switch stack running Multiple Spanning Tree (MST) is connected to a switch
running Rapid Spanning Tree Protocol (RSTP), the MST switch acts as the root bridge and runs
per-VLAN spanning tree (PVST) simulation mode on boundary ports connected to the RST switch.
If the allowed VLAN on all trunk ports connecting these switches is changed to a VLAN other than
VLAN 1 and the root port of the RSTP switch is shut down and then enabled, the boundary ports
connected to the root port move immediately to the forward state without going through the PVST+
slow transition.
There is no workaround.
Trunking
•
IP traffic with IP options set is sometimes leaked on a trunk port. For example, a trunk port is a
member of an IP multicast group in VLAN X but is not a member in VLAN Y. If VLAN Y is the
output interface for the multicast route entry assigned to the multicast group and an interface in
VLAN Y belongs to the same multicast group, the IP-option traffic received on an input VLAN
interface other than one in VLAN Y is sent on the trunk port in VLAN Y because the trunk port is
forwarding in VLAN Y, even though the port has no group membership in VLAN Y.
There is no workaround. (CSCdz42909).
•
For trunk ports or access ports configured with IEEE 802.1Q tagging, inconsistent statistics might
appear in the
show interfaces counters
privileged EXEC command output. Valid IEEE 802.1Q
frames of 64 to 66 bytes are correctly forwarded even though the port LED blinks amber, and the
frames are not counted on the interface statistics.
There is no workaround. (CSCec35100).
VLAN
•
If the number of VLANs times the number of trunk ports exceeds the recommended limit of 13,000,
the switch can fail.
The workaround is to reduce the number of VLANs or trunks. (CSCeb31087)
•
When line rate traffic is passing through a dynamic port, and you enter the
switchport access vlan
dynamic
interface configuration command for a range of ports, the VLANs might not be assigned
correctly. One or more VLANs with a null ID appears in the MAC address table instead.
The workaround is to enter the
switchport access vlan dynamic
interface configuration
command
separately on each port. (CSCsi26392)
•
When many VLANs are configured on the switch, high CPU utilization occurs when many links are
flapping at the same time.
The workaround is to remove unnecessary VLANs to reduce CPU utilization when many links are
flapping. (CSCtl04815)
Important Notes
•
IPv4 Static Routing Notes, page 14
•
61000-4-3 Standard Notes, page 14
