Cisco Nexus 5000 Series and Cisco Nexus 2000 Series Release Notes, for Cisco NX-OS Release 5.0(2)N1(1) and NX-OS Release 5.0(2)N2(1) OL-22747-02, December 2010)

Send documentation comments to [e-mail]
43
Cisco Nexus 5000 Series and Cisco Nexus 2000 Series Release Notes, for Cisco NX-OS Release 5.0(2)N1(1) and NX-OS Release 5.0(2)N2(1)
OL-22747-02
Caveats
Symptom:The DWRR scheduling on the Cisco Nexus 2248 and Cisco Nexus 2232 Fabric Extenders
is not accurate. As a result, the class of traffic that presents more traffic is given a larger share of
the bandwidth.
Workaround: Strict priority scheduling can be used (enter the priority keyword in the queuing
policy command) to provide scheduling precedence.
• CSCti62723
Symptom: An inconsistent MST spanning tree status exists between the vPC primary and secondary
switches. This can occur with recent MST configuration changes when manually shutting vPC
member ports or when the vPC secondary switch reloads.
Workaround: Perform a shut/no shut on affected vPC member ports on the primary switch.
• CSCti76612
Symptom: Slow throughput is observed for FCoE and FC traffic from a Cisco Nexus 5000 Series
switch when using port 4 of the N5K-M1060 FC module in a Cisco Nexus 5000 Series switch. Poor
performance is seen even on other Fiber Channel interfaces if port 4 is part of a SAN port channel.
Workaround: Do not use port 4 in the N5K-M1060 FC module. This issue is resolved in NX-OS
Release 5.0(2)N1(1).
• CSCti87640
Symptom: On a Cisco Nexus 5000 Series switch running NX-OS Release 4.2(1)N2(1) or earlier
releases, FEX Active-Active interfaces may remain in the down or not connected state after repeated
interface resets in a short duration of time. This occurs when a Cisco Nexus 2148 Fabric Extender
or Nexus 2248 Fabric Extender is in an Active/Active topology and the high debounce timer is
configured on the FEX interfaces.
Workaround: Issue a shut/no shut on the interface. This is resolved in NX-OS Release 5.0(2)N1(1)
and later releases.
• CSCti92608 N5k:
Symptom: In a Cisco Nexus 5000 Series switch running NX-OS Release 4.2(1)N2(1) or NX-OS
Release 5.2(1)N1(1), after an ISSU upgrade, newly configured vFCs do not come up for CNA's
connected to a Cisco Nexus 2232 Fabric Extender or Ethernet expansion module.
This can occur when an ISSU upgrade is performed on a Cisco Nexus 5000 Series switch and after
the switch comes up, FCoE is configured on the Cisco Nexus 2232 Fabric Extender and/or the
Ethernet expansion module interfaces which were in a down or not connected state before the
upgrade.
Workaround: Reload the Cisco Nexus 2232 Fabric Extender or the Ethernet expansion module.
This issue is fixed in NX-OS 5.0(2)N1(1)and later releases.
• CSCti96718
Symptom: a Cisco Nexus 5000 Series switch running NX-OS Release 4.2(1)N2(1) might fail if a
connected FEX does not come online.
Workaround: Make sure the FEX connected to the Cisco Nexus 5000 Series switch is configured
correctly and comes online, or, do not do any SNMPget operations on the Cisco Nexus 5000 Series
switch which is connected to a FEX that is not coming online.
• CSCth18541 802.3
Symptom: The show interface Ex/y flowcontrol counters increment when receiving PFC Pause
frames This can occur when working with Gen 1 CNA's.
Workaround: This issue is resolved.