Installing a load balancer

Managed Kubernetes services such as Google or IBM Cloud will provide an external load balancer. Since our Kubernetes environment is standalone, we do not have an external load balancer; we install and use keepalived as a load balancer.

The keepalived load balancer depends on the ip_vs kernel module to be loaded. Follow these steps:

1. Make sure that the ip_vs kernel module is loaded:

$ sudo lsmod | grep ^ip_vs
ip_vs_wlc 12519 0
ip_vs 145497 2 ip_vs_wlc

2. If the preceding does not show any output, load the module:

$ sudo ipvsadm -ln
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn

3. Run sudo lsmod | grep ^ip_vs to make sure that the module is loaded.
4. Add ip_vs to the module list so that it is loaded automatically on reboot:

$ echo "ip_vs" | sudo...