Cisco Nexus 5000 Series and Cisco Nexus 2000 Series Release Notes,Cisco NX-OS Release 5.1(3)N2(1a) and NX-OS Release 5.1(3)N2(1)

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Cisco Nexus 5000 Series and Cisco Nexus 2000 Series Release Notes, Cisco NX-OS Release 5.1(3)N2(1a) and NX-OS Release 5.1(3)N2(1)
OL-26652-02
Limitations
– Use a dedicated front panel port as a vPC+ keepalive. The port should be in CE mode.
– Use a dedicated VLAN to carry the keepalive interface. The VLAN should be CE VLAN.
– Add the management keyword to the corresponding SVI so that the failure of a Layer 3 module
will not bring down the SVI interface.
– Enter the dual-active exclude interface-vlan keepalive-vlan command to prevent the SVI from
going down on the secondary when a peer-link goes down.
• Fabricpath requires 802.1q tagging of inner Ethernet header of the packet. Native VLAN packets
that are sent by a Cisco Nexus 7000 Series switch are not tagged. As a result, a Cisco Nexus 5000
Series switch drops packets due to packet parsing errors. To work around this issue, enable vlan
dot1q tag native on the Cisco Nexus 7000 Series switch to force 802.1q tagging of native VLAN
packets.
• SPAN traffic is rate-limited on Cisco Nexus 5500 Series switches platforms to prevent impact to
production traffic:
– SPAN is rate-limited to 5 Gbps per ASIC (every 8 ports share one ASIC).
– SPAN is rate-limited to 0.71 Gbps per monitor source port when the RX traffic on the port
exceeds 5 Gbps.
For details, see CSCti94902.
• Cisco Nexus 5548UP and Cisco Nexus 5598UP switches with a fibre-channel connection to HP
Virtual Connect modules experience link destabilization and packet loss when the speed is set to
8GB. To work around this issue, leave the speed set to 4GB. For details, see CSCtx52991.
Configuration Synchronization Limitation
When you remove a switch profile using the no switch-profile name [all-config | local-config]
command, the configuration in the switch profile is not immediately removed from the running
configuration. The following warning message appears:
WARNING: Deleting switch-profile will remove all commands configured under
switch-profile. Are you sure you want to delete all switch-profile commands from the
system ?
Are you sure? (y/n) [n]
For current information about this issue, refer to CSCtl87260.
Limitations on the Cisco Nexus 5010 and Cisco Nexus 5020
The limitations on the Cisco Nexus 5010 switch and the Cisco Nexus 5020 switch are as follows:
• Traffic going out the Ethernet SPAN destination is always tagged. The SPAN destination can be in
the access or trunk mode and frames on the SPAN source port can be tagged or untagged. Frames
are always tagged internally as they travel through the system. Information about whether the frame
was originally tagged or untagged, as it appeared in the SPAN source, is not preserved in the SPAN
destination. The spanned traffic exiting the SPAN destination port always has the VLAN tag on it.
The correct VLAN tag is applied on the frame as it goes out the SPAN destination. The only
exception is if frames ingress on a SPAN source port on an invalid VLAN. In this case, vlan 0 is
applied on a spanned frame.