kube-loxilb is loxilb's implementation of kubernetes service load-balancer spec which includes support for load-balancer class, advanced IPAM (shared or exclusive), lb services on multus pods etc. kube-loxilb runs as a deloyment set in kube-system namespace.
Another loxilb component known as loxi-ccm also provides implementation of kubernetes load-balancer spec but it runs as a part of cloud-provider and provides load-balancer life-cycle management as part of it. If one does not need a cloud-provider or wants to integrate loxilb with their existing cloud-provider, one can use or include loxi-ccm as a part of it. If not kube-loxilb is the right component to use.
kube-loxilb is a standalone implementation of kubernetes load-balancer spec which does not depend on cloud-provider. It runs as a kube-system deployment and provisions load-balancer based on load-balancer class. It only acts on load-balancers for the LB classes that is provided by itself. This also allows us to have different load-balancers working together in the same K8s environment.
1.Make sure loxilb docker is downloaded and installed properly. One can follow guides here or refer to various other documentation
2.Download the loxilb config yaml :
wget https://github.com/loxilb-io/kube-loxilb/raw/main/manifest/kube-loxilb.yaml
3.Modify arguments as per user's needs :
args:
- --loxiURL=http://12.12.12.1:11111
- --externalCIDR=123.123.123.1/24
#- --externalSecondaryCIDRs=124.124.124.1/24,125.125.125.1/24
#- --externalCIDR6=3ffe::1/96
#- --monitor
#- --setBGP=false
#- --setLBMode=1
#- --setUniqueIP=false
The arguments have the following meaning :
- loxiURL : API server address of loxilb. This is the docker IP address loxilb docker of Step 1.
- externalCIDR : CIDR or IPAddress range to allocate addresses from. By default address allocated are shared for different services(shared Mode)
- externalCIDR6 : Ipv6 CIDR or IPAddress range to allocate addresses from. By default address allocated are shared for different services(shared Mode)
- monitor : Enable liveness probe for the LB end-points (default : unset)
- setBGP : Use BGP to advertise this service (default :false). Please check here how it works.
- setLBMode : 0, 1, 2
0 - default (only DNAT, preserves source-IP)
1 - onearm (source IP is changed to load balancer’s interface IP)
2 - fullNAT (sourceIP is changed to virtual IP) - setUniqueIP : Allocate unique service-IP per LB service (default : false)
- externalSecondaryCIDRs: Secondary CIDR or IPAddress ranges to allocate addresses from in case of multi-homing support
- Apply the following :
kubectl apply -f kube-loxilb.yaml
- The above should make sure kube-loxilb is successfully running. Check kube-loxilb is running :
kubectl get pods -A | grep kube-loxilb
- Finally to create service LB, we can use and apply the following template yaml :
(Note - Check loadBalancerClass and other loxilb specific annotation)
apiVersion: v1
kind: Service
metadata:
name: iperf-service
annotations:
# If there is a need to do liveness check from loxilb
loxilb.io/liveness: "yes"
# Specify LB mode - one of default, onearm or fullnat
loxilb.io/lbmode: "default"
# Specify loxilb IPAM mode - one of ipv4, ipv6 or ipv6to4
loxilb.io/ipam: "ipv4"
# Specify number of secondary networks for multi-homing
# Only valid for SCTP currently
# loxilb.io/num-secondary-networks: "2
spec:
loadBalancerClass: loxilb.io/loxilb
selector:
what: perf-test
ports:
- port: 55001
targetPort: 5001
type: LoadBalancer
---
apiVersion: v1
kind: Pod
metadata:
name: iperf1
labels:
what: perf-test
spec:
containers:
- name: iperf
image: eyes852/ubuntu-iperf-test:0.5
command:
- iperf
- "-s"
ports:
- containerPort: 5001Users can change the above as per their needs.
- Verify LB service is created
kubectl get svc