Monthly Archives: April, 2013

Nexus 1000v Config for UCS with iSCSI boot.

Inside UCS, all VLANs are trunked and not native, EXCEPT the iSCSI VLAN; The iSCSI NICs needed to be set as the Native VLAN to allow the hardware to boot from the iSCSI devices, since there was no OS to allow us to assign a specific VLAN until after boot; Inside the Standard vSwitches that …

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N1KV Layer 3 mode

Change svs mode from Layer 2 to Layer 3 in Cisco Nexus 1000V. The configuration in the highlighted code is optional to change svs mode from Layer 2 to Layer 3. Note switch(config)# svs-domain switch(config-svs-domain)# no control vlan Warning: Config saved but not pushed to vCenter Server due to inactive connection! switch(config-svs-domain)# no packet vlan Warning: …

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N1Kv installation on an UCS System

If you are installing a Cisco Nexus 1000V in an environment where the upstream switch does not support static port channels, such as the Cisco Unified Computing System (UCS), you must use the channel-group auto mode on mac-pinning command instead of the channel-group auto mode command

N1K VEM Upstream Switch Prerequisites

The following spanning tree prerequisites apply to the switch upstream from the Cisco Nexus 1000V on the ports connected to the VEM spanning-tree port type edge trunk spanning-tree bpdu filter spanning-tree bpdu guard.

Nexus1000v VSM/VEM communication over Layer3

Over Layer 3 (recommended): Communication between the VSM and the VEM is done through Layer 3, using the management interface of the VSM and a VMkernel interface of the VEM. Layer 3 connectivity mode is the recommended mode. The Layer 3 mode encapsulates the control and packet frames through User Datagram Protocol (UDP). This process requires …

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Configure N5K System Qos for FCOE and Jumbo MTU

N5K-1# sh pol sys Type network-qos policy-maps =============================== policy-map type network-qos default-nq-policy class type network-qos class-fcoe match qos-group 1 pause no-drop mtu 2158 class type network-qos class-default match qos-group 0 mtu 1500 Service-policy (qos) input: default-in-policy policy statistics status: enabled Class-map (qos): class-fcoe (match-any) Match: cos 3 set qos-group 1 N5K-1# conf t Enter configuration …

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Nexus 5548 and unsupported CNA

Nexus 5548 Troubleshooting Possible Cause The type of Converged Network Adapter might not be supported. Solution Ensure that the type of adapter is supported. The FCoE interface only supports a Generation-2 Converged Network Adapter. Possible Cause The FCoE class-fcoe system class is not enabled in the QoS configuration. Solution For a Cisco Nexus 5548 switch, …

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The Cisco Nexus 5000 Series switch is a Layer 2 device. This means it does not fragment frames. As a result, the switch cannot have two ports in the same Layer 2 domain with different maximum transmission units (MTUs). A per-physical Ethernet interface MTU is not supported. Instead, the MTU is set according to the QoS classes. You modify …

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MTU over vPC N7K.

Jumbo frames are enabled by default on the vPC peer link. No MTU size configured, just system jumbomtu 9216 (Which is default) N7K-N7K-DC1-3(config-if)# ping pack 9000 PING ( 9000 data bytes 9008 bytes from icmp_seq=0 ttl=254 time=8.365 ms Request 1 timed out 9008 bytes from icmp_seq=2 ttl=254 time=8.141 ms Request 3 …

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UCS in FC mode…

Configuration of a port in FC Switching Mode. interface fc1/32 switchport mode E channel-group 100 force no shutdown The same port in FC Endhost Mode : interface fc1/32 switchport mode NP switchport trunk mode on channel-group 100 force no shutdown