SmartLB

Use LVS as external loadbalancer for kubernetes ingress traffic

And this LB was implemented by using kubernetes operator

apiVersion: lb.my.domain/v1
kind: SmartLB
metadata:
  name: echo-server
spec:
  service: echo-server
  namespace: default
  vip: 192.168.122.100
  scheduler: rr

Pre-condition

• kube-proxy must use IPVS mode with strict ARP enabled
• Prior to v1.19 , ExternalPolicyForExternalIP must be set true if use Local mode

Architecture Overview

Installation

Way1, installed on LVS server (recommended)

• Compile to get the binary program, find the environment which have golang 1.13+ and kubectl, kustomize installed and configure with cluster

git clone https://github.com/JinlongWukong/smartLB.git
cd smartLB
go build  -o smartlb main.go

• Install CRDs to k8s cluster

make install 

• Copy the smartlb binary program to LVS server and run

# Before run 
# need prepare tls certificate under /tmp/k8s-webhook-server/serving-certs/ as name tls.crt, tls.key
# need figure out which interface should be used for vip binding
./smartlb --bind-interface eth0

# For more options, reference as below
Usage of ./smartlb:
  -auto-sync
        whether enable ipvs rules auto refresh (default true)
  -bind-interface string
        which interface the vip will bind
  -enable-leader-election
        Enable leader election for controller manager. Enabling this will ensure there is only one active controller manager.
  -enable-local-mode
        whether run this controller on lvs server (default true)
  -ip-range string
        define vip pool range
  -kubeconfig string
        Paths to a kubeconfig. Only required if out-of-cluster.
  -master --kubeconfig
        (Deprecated: switch to --kubeconfig) The address of the Kubernetes API server. Overrides any value in kubeconfig. Only required if out-of-cluster.
  -metrics-addr string
        The address the metric endpoint binds to. (default ":8081")
  -sync-period duration
        the interval of how often ipvs rules are refresh (default 1m0s)

Way2, installed inside k8s cluster

Notes: This way looks normal, but will be a little complicated to deploy, also need a remote agent running at LVS server as subscribe webhook

Please follow kubebuilder document to learn how to install it in this way

Notices

• This project has been verified on kubernetes v1.18.3

License