Use the vMotion TCP/IP stack to isolate traffic for vMotion and to assign a dedicated default gateway, routing table, and DNS configuration for this traffic. To enable the vMotion TCP/IP stack, assign a new VMkernel adapter to it.

By using a separate TCP/IP stack, you can handle vMotion and cold migration traffic according to the topology of the network and as required for your organization:

  • Route the traffic for migration of powered on or powered off virtual machines by using a default gateway. The gateway must be different from the gateway assigned to the default stack on the host.

    By using a separate default gateway, you can use DHCP for IP address assignment to the VMkernel adapters for migration in a flexible way.

  • Assign a separate set of buffers and sockets.
  • Avoid routing table conflicts that might otherwise appear when many features are using a common TCP/IP stack.
  • Isolate traffic to improve security.

Prerequisites

Verify that the host is running ESXi 6.0 or later

Procedure

  1. In the vSphere Web Client, navigate to the host.
  2. Click the Configure tab.
  3. Select Networking, and click VMkernel adapters.
  4. Click Add host networking.
  5. On the Select connection type page, select VMkernel Network Adapter and click Next.
  6. On the Select target device page, select the switch for the VMkernel adapter, and click Next.
    Option Description
    Select an existing network Use the physical adapter configuration of an existing distributed port group to send data from the VMkernel adapter to the external network.
    Select an existing standard switch Use the physical adapter configuration for the VMkernel adapter of an existing standard switch.
    New vSphere standard switch Assign a new physical adapter configuration for the VMkernel adapter on a new standard switch.
  7. On the Port properties page, select vMotion from the TCP/IP stack drop-down menu.
    The vMotion traffic becomes the only service that is enabled. You cannot use this VMkernel adapter for traffic types other than vMotion.
  8. Set the label, VLAN ID, and IP mode of the VMkernel adapter, and click Next.
  9. (Optional) On the IPv4 settings page, select an option for obtaining IP addresses.
    Option Description
    Obtain IPv4 settings automatically Use DHCP to obtain IP settings. A DHCP server must be present on the network.
    Use static IPv4 settings

    Enter the IPv4 IP address and subnet mask for the VMkernel adapter.

    The VMkernel Default Gateway and DNS server addresses for IPv4 are obtained from the selected TCP/IP stack.

    Select the Override default gateway for this adapter check box and enter a gateway address, if you want to specify a different gateway for the VMkernel adapter.
    Note: Selected netstack should have the default gateway explicitly on each host.
  10. (Optional) On the IPv6 settings page, select an option for obtaining IPv6 addresses.
    Option Description
    Obtain IPv6 addresses automatically through DHCP Use DHCP to obtain IPv6 addresses. A DHCPv6 server must be present on the network.
    Obtain IPv6 addresses automatically through Router Advertisement Use router advertisement to obtain IPv6 addresses.

    In ESXi 6.5 and later router advertisement is enabled by default and supports the M and O flags in accordance with RFC 4861.

    Static IPv6 addresses
    1. Click Add IPv6 address to add a new IPv6 address.
    2. Enter the IPv6 address and subnet prefix length, and click OK.
    3. To change the VMkernel default gateway, click Override default gateway for this adapter.

    The VMkernel Default Gateway address for IPv6 is obtained from the selected TCP/IP stack.

  11. Review your settings selections on the Ready to complete page and click Finish.

Results

After you create a VMkernel adapter on the vMotion TCP/IP stack, you can use only this stack for vMotion on this host. The VMkernel adapters on the default TCP/IP stack are disabled for the vMotion service. If a live migration uses the default TCP/IP stack while you are configuring VMkernel adapters with the vMotion TCP/IP stack, the migration completes successfully. However, the involved VMkernel adapters on the default TCP/IP stack are disabled for future vMotion sessions.

What to do next

Assign a default gateway, and configure the DNS settings, congestion control, and maximum number of connections for the vMotion TCP/IP stack.

For more information on how to change the configuration of a TCP/IP stack on a host, see the vSphere Networking documentation.