Use Traceflow to inspect the path of a packet. Traceflow traces the transport node-level path of a packet. The trace packet traverses the logical switch overlay, but is not visible to interfaces attached to the logical switch. In other words, no packet is actually delivered to the test packet’s intended recipients.

Note: Traceflow is not supported for a VLAN-backed logical switch or segment.

Procedure

  1. From your browser, log in with admin privileges to an NSX Manager at https://<nsx-manager-ip-address>.
  2. Select Plan & Troubleshoot > Troubleshooting Tools > Traceflow.
  3. Select an IPv4 or IPv6 address type.
  4. Select a traffic type.
    For IPv4 addresses the traffic type choices are Unicast, Multicast, and Broadcast. For IPv6 address the traffic type choices are Unicast or Multicast.

    Note: Multicast and broadcast are not supported in a VMware Cloud (VMC) environment.

  5. (Optional) Select a protocol and provide related information.
    Protocol Parameters
    DHCP Select a DHCP OP code: Boot Request or Boot Reply.
    DHCPv6 Select a DHCP message type: Solicit, Advertise, Request, or Reply.
    Note: This option is available only when IPv6 is selected for IP Address.
    DNS Specify an address and select a message type: Query or Response.
    ICMP Specify an ICMP ID and a sequence.
    ICMPv6 Specify an ICMP ID and a sequence.
    Note: This option is available only when IPv6 is selected for IP Address.
    TCP Specify a source port, a destination port, and TCP flags.
    UDP Specify a source port and a destination port.
    For the TCP protocol, note the following:
    • The default flag is SYN.
    • SYN cannot be combined with RST or FIN.
    • If SYN is not selected, you must select ACK or RST.
    • ACK cannot be combined with FIN, PSH, or URG.
  6. Specify the source and destination information according to the traffic type.
    Traffic Type Source Destination
    Unicast Select a VM or a logical port. For a VM:
    • Select a VM from the drop-down list.
    • Select a virtual interface.
    • The IP address and MAC address are displayed if VMtools is installed in the VM, or if the VM is deployed using OpenStack plug-in (address bindings will be used in this case). If the VM has more than one IP address, select one from the drop-down list.
    • If the IP address and MAC address are not displayed, enter the IP address and MAC address in the text boxes.
    For a logical port:
    • Select an attachment type: VIF, DHCP, Edge Uplink, or Edge Centralized Service.
    • Select a port.
    		Select a VM, a logical port, or IP-MAC. For a VM:
    • Select a VM from the drop-down list.
    • Select a virtual interface.
    • The IP address and MAC address are displayed if VMtools is installed in the VM or if the VM is deployed using OpenStack plug-in (address bindings will be used in this case). If the VM has more than one IP address, select one from the drop-down list.
    • If the IP address and MAC address are not displayed, enter the IP address and MAC address in the text boxes.
    For a logical port:
    • Select an attachment type: VIF, DHCP, Edge Uplink, or Edge Centralized Service.
    • Select a port.
    For IP-MAC:
    • Select the trace type (layer 2 or layer 3). For layer 2, enter an IP address and a MAC address. For layer 3, enter an IP address.
    Multicast Same as above. Enter an IP Address. It must be a multicast address from 224.0.0.0 - 239.255.255.255.
    Broadcast Same as above. Enter a subnet prefix length.
  7. (Optional) Click Advanced Settings to see the advanced options.
    In the left column, enter the desired values or input for the following fields:
    Option Description
    Frame Size The default is 128.
    TTL The default is 64.
    Timeout (ms) The default is 10000.
    Ethertype The default is 2048.
    Payload Type Select Base64, Hex, Plaintext, Binary, or Decimal.
    Payload Data Payload formatted based on selected type.
  8. Click Trace.

    The output includes a graphical map of the topology and a table listing the observed packets. The first packet listed has the observation type Injected and shows the packet that is injected at the injection point.

    You can apply a filter (All, Delivered, Dropped) on the observations that are displayed. If there are dropped observations, the Dropped filter is applied by default. Otherwise, the All filter is applied.

    The graphical map shows the backplane and router links. Note that bridging information is not displayed.