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posted Sep 28, 2013, 3:17 PM by Rick McGee   [ updated Sep 30, 2013, 8:41 PM ]
Video 30
N1Kv Modes
  • Minimum of 3 NIC's / vNIC's required
    • Used for Control (management), Packet, and Data
L2 - VEM's must be on the same VLAN as the VSM control VLAN
L3- This is the recommended mode
  • VEM traffic is encapsulated in UDP 4785
  • "capability" l3control" needed on vETH profiles used for ESXi VMKERNEL before moving from vSwitch0
  • System VLAN for both vETH and ETH
Important to note that VLAN's for Port Profiles used for Data Plane not be overlapping with VLAN's used in Port Profiles for control and Packet Planes- Otherwise VEM may leave VSM
vPC-HM (host mode) and Pinning in the N1Kv
  • vPC-HM configured on the Eth port profiles, not any vEth port profiles
  • Has nothing to do with up stream switches running vPC, even though it may be in some cases
  • On: "channel-group auto group on"
  • Active (LACP): "channel-group auto mode active"
  • Sub-Group Manual Pinning; "channel-group mode on sub-group manual"
  • Sub-Group CDP Pinning; "channel-group auto mode sub-group CDP" (NOT USED)
    • Two Eth uplink ports in the same port profile will form a port-channel only if the links northbound are from the same switch
  • MAC-Pinning (Recommended Mode):  " channel-group auto mode on MAC-Pinning
    • This is recommended with UCS B Series
  • Load-balances the available links (i.e. port-channel) based upon mac-address of the VM. So VM1 will flow through say vmnic0 and VM2 will flow through vmnic1, where vmnic0 and vmnic1 is this vPC-HM port-channel. If vmnic0 fails, then all VM traffic will start to flow on vmnic1 as normal HA
  • This is a load-balanced based upon the Cisco Discovery Protocol (CDP) on the upstream switch.
  • This is typically not used and is not recommended
  • Link Aggregation Control Protocol (LACP) provides a better hashing algorithm to load-balance on the available uplinks in that port-channel providing better utilization of the links and allows that VM to use all available links
  • LACP can be used if all interfaces are connected to the same physical switch
  • If the uplink interfaces are connected to two separate physical up stream switches, then a Multi-Chassis EtherChannel technology needs to be available on those upstream switches for LACP to be used.
    • Example of Cisco switches that has the capabilities on all Nexus 7K,5K,2K using vPC and Cisoc Catalyst 6K's using VSS or Catalyst 3700 using stacking
Verify Dynamic Pinning
  • Look to match the LTL (Local Target Logic) values and the SGID (Sub-Group ID) values
  • Number of "vemcmd" that can be run directly in EXSi
  • In order to run these commands you must tell the VSM which VEM module you wish to run the command on
    • module VEM [# of VEM] execute
    • module vem3 execute vem cmd show port
    •  module vem3 execute vem cmd show pinning
    • module vem3 execute vem cmd show port-LTL-Number
LACP Port Channels in N1Kv
  • LACP can be used if one is not using a N1Kv with a UCS system
    • e.g. N1Kv is used with C-200 server with 2 10GE uplinks from SFP's to a single Nexus 5k or a pair or Nexus 5K's running vPC
  • LACP negotiation can be offloaded from VSM to VEM's
    • This maybe need to establish initial control path from VEM to VSM or simply due to failure of both VSM's