Loudmouth requires IPv6 multicast in order for VxRail Manager to perform a successful VxRail node discovery. IPv6 multicast is required only on the ‘Private Management Network’, this is an isolated management network solely for auto-discovery of the VxRail nodes during install or expansion. The default VLAN ID for the private network is 3939, which is configured on each VxRail node from the factory, this VLAN needs to be configured on the TOR switches and remains isolated on the TORs. If you wish to deviate from the default of VLAN 3939 then each node will need to be modified onsite otherwise node discovery will fail.
The following is a simple IPv6 ping test to ensure communication between VxRail Manager and a VxRail node.
Firstly gather the IPv6 address from the VxRail node via the ESXi console:
esxcfg-vmknic -l | grep vmk0
Returns the following IPv6 address: fe80::250:56ff:fe68:389e
VxRail Manager network interface eth1 is connected to the Private Network as you can see from the following screen captures:
To run the comms test we use the ping6 command from the VxRail Manager console to test comms between the VxRail node ESXi vmk0 and VxRail Manager eth1 interfaces.
VxRail node ESXi vmk0 IPv6 address as per above is: fe80::250:56ff:fe68:389e
ping6 -I eth1 fe80::250:56ff:fe68:389e
Successful communication over the IPv6 multicast network!