Load Balancing DNS with Zevenet

Load balancing DNS with Zevenet. After getting the server setup with its initial network configuration. First thing would be to setup a virtual NIC for the DNS traffic. Pretty straight forward, pick the parent interface, give it a name, and an available IP on the network.

Zevenet vNIC config
vNIC Config

In this example I’m not using VLANs, so the VLAN tag shows up as the virtual interface name.

Zevenet vNIC
vNIC

To setup the load balancer, go to LSLB, then Farms. Select the virtual interface we just created, give it a port number of 53, protocol type is UDP, and NAT type is NAT. For the service setting, pick round robin, turn off persistence, set health checks to ping.

Load Balancing DNS Zevenet
Load Balancer Config

Now click on add backend, enter in each of your DNS servers, giving them both a priority and weight of 1.

Load Balancing Zevenet add backend

One caveat with load balancing DNS with Zevenet is that all the traffic will appear that it is coming from the load balancer, so any logs on the DNS servers will have the load balancer’s IP address. I try to alleviate the issue by setting the 2nd DNS in the client’s DNS settings to one of the DNS servers. So DHCP hands out the load balancer’s virtual interface IP as the first DNS server, and one of the DNS server’s IP addresses as the 2nd.