Notes on VMware NSX L2 Bridging

Here are my course notes from the VCP6-NV v6.2 Course touching on VMware NSX L2 Bridging. As always, I will keep posting the rest of my notes in hopes it will assist someone else as it did me.

 

6.1

  • L2 bridging creates L2 adjacency between a physical network and a virtualized network
  • Can be accomplished through software (NSX) or hardware gateways from certified partners
  • Methods:
    • Software
      • Using NSX includes software based VXLAN gateways which are redundant and scalable
    • Hardware
      • Includes wire speed 10/40/100 VXLAN gateway and hardware based L2 VXLAN gateway
        • HS
        • Single point of integration with VMware NSX for hardware gateway
        • NSX 6.2
  • Use Cases – vms on logical switches to have direct L2 access to the physical network in:
    • P2V migrations where IP cannot change
    • Extending virtual services in logical switch to external devices
    • When extending physical network services to vms in logical switches
    • When extending access to existing physical network and security resources
  • ********L2 bridging is not a solution for
    • VXLAN to VXLAN
    • VLAN to VLAN
    • Data center interconnects
  • DLR is used to conduct the bridge and the routing capabilities are not required
  • VXLAN to VLAN takes place in the Kernel
  • Interoperability
    • VXLAN and vlan configured for bridging must be accessible from same distributed switch
    • This is usually a dist switch in the NSX edge cluster which allows you to minimize the span of the needed VLAN to just the racks where NSX edge cluster is
  • Scalability
    • Not resource intensive
    • Comparable to standard vxlan traffic processing
  • Loop Prevention
    • Only one bridge is active per vxlan-vlan at any time
    • Occurs by detect and filter of same packet received through diff uplink by matching the MAC
  • VXLAN to VLAN function
    • Bridge instance (host) sends learned MAC table to NSX controller
    • If the bridge instance dies the new bridge instance gets MAC info from the NSX controller
    • Uses RARP to update table of physical switches
  • Bridge Failure
    • Standby logical router on other host
  • L2 Bridging Differences
    • NSX6.1
      • Cannot be in distributing routing and extend a LVAN bridge
    • NSX6.2
      • DL routing and bridging can

 

 

6.2 Intro to Hardware L2 Gateways

  • Benefits of multiple bridging instances
    • Single
      • Has a vxlan-vlan pair per logical switch and bandwidth is limited
      • Bridge vlan extends to reach physical
    • Multiple
      • Multiple bridging instance for separate VXLAN-vlan pairs
        • Scaling is not to add more pairs to existing bridge but to create more bridge instances
    • Hardware L2 Gateway
      • Device that can have a VXLAN tunnel endpoint (VTEP) configured
      • L2 hardware VTEP
        • VTEP on physical switch rather than in hypervisor
      • Open vSwitch¬† Database (OVSDB)
        • Openflow config protocol used to manage open vswitch implementations
        • Extensible not reliant on multicast
      • Open vSwitch (OVS)
        • Open source vSwitch
      • Replication Servicer Nodes
        • Hardware vtep use hypervisor to replicate multidestination traffic. Replication service node is a host chosen for this
      • Replication Node Cluster
        • Esxi hosts chosen to hangle the replication of multidesitnaion traffic
      • Bidirectional Forwarding Detection (BFD)
        • Detects 2 forwarding device connected by same link

 

plasebikan