ALB (Another Load Balancer) is a Kubernetes Gateway powered by OpenResty with years of production experience from Alauda.
Note: We are in the process of preparing the necessary documentation and refactoring the code for open source. More information and detailed usage will be made available soon.
- Isolation and Multi-Tenant: With ALB operator, multiple ALB instances can be created and managed in one cluster. Each tenant can has a group of dedicated ALB instances.
- Ingress and Gateway API Support: Users can flexibly choose between Ingress and Gateway API according to their own preferences.
- Flexible User Defined Traffic Rule: ALB provides a traffic rule DSL that can support more complex traffic matching and distribution scenarios that beyond the capabilities of standard Ingress and Gateway API.
- Multiple Protocol Support: ALB can manage HTTP, HTTPS, TCP and UDP traffic.
- Create a kind cluster
helm repo add alb https://alauda.github.io/alb/;helm repo update;helm search repo|grep alb
helm install alb-operator alb/alauda-alb2
cat <<EOF | kubectl apply -f -
apiVersion: crd.alauda.io/v2beta1
kind: ALB2
metadata:
name: alb-demo
namespace: kube-system
spec:
address: "172.20.0.5" # the ip address of node where alb been deployed
type: "nginx"
config:
networkMode: host
loadbalancerName: alb-demo
nodeSelector:
alb-demo: "true"
projects:
- ALL_ALL
replicas: 1
EOF
cat <<EOF | kubectl apply -f -
apiVersion: apps/v1
kind: Deployment
metadata:
name: hello-world
labels:
k8s-app: hello-world
spec:
replicas: 1
selector:
matchLabels:
k8s-app: hello-world
template:
metadata:
labels:
k8s-app: hello-world
spec:
terminationGracePeriodSeconds: 60
containers:
- name: hello-world
image: docker.io/crccheck/hello-world:latest
imagePullPolicy: IfNotPresent
---
apiVersion: v1
kind: Service
metadata:
name: hello-world
labels:
k8s-app: hello-world
spec:
ports:
- name: http
port: 80
targetPort: 8000
selector:
k8s-app: hello-world
---
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
name: hello-world
spec:
rules:
- http:
paths:
- path: /
pathType: Prefix
backend:
service:
name: hello-world
port:
number: 80
EOF
Now you visit the app by curl http://${ip}
Complex traffic matching and distribution patterns can be configured by Frontend
and Rule
.
syntax of rule's dslx
apiVersion: crd.alauda.io/v1
kind: Frontend
metadata:
labels:
alb2.cpaas.io/name: alb-demo # required, indicate the ALB instance to which this Frontend belongs to
name: alb-demo-00080
namespace: kube-system
spec:
backendProtocol: "" # http|https
certificate_name: "" # $secret_ns/$secret_name
port: 80
protocol: http # protocol of this Frontend itself
---
apiVersion: crd.alauda.io/v1
kind: Rule
metadata:
labels:
alb2.cpaas.io/frontend: alb-demo-00080 # required, indicate the Frontend to which this rule belongs
alb2.cpaas.io/name: alb-demo # required, indicate the ALB to which this rule belongs
name: alb-demo-00080-topu
namespace: kube-system
spec:
backendProtocol: "" # as same as Frontend
certificate_name: "" # as same as Frontend
dslx: # this rule matches url starts with /app-a or /app-b and method is post,and url param's group is vip, and host is *.app.com, and header's location is east-1 or east-2 and has a cookie name is uid, and source IPs come from 1.1.1.1-1.1.1.100
- type: METHOD
values:
- - EQ
- POST
- type: URL
values:
- - STARTS_WITH
- /app-a
- - STARTS_WITH
- /app-b
- type: PARAM
key: group
values:
- - EQ
- vip
- type: HOST
values:
- - ENDS_WITH
- .app.com
- type: HEADER
key: LOCATION
values:
- - IN
- east-1
- east-2
- type: COOKIE
key: uid
values:
- - EXIST
- type: SRC_IP
values:
- - RANGE
- "1.1.1.1"
- "1.1.1.100"
enableCORS: false
priority: 5 # the lower the number, the higher the priority
serviceGroup:
services:
- name: hello-world
namespace: default
port: 80
weight: 100
alb.ingress.cpaas.io/rewrite-request: |
{"headers_remove":["h1"],"headers":{"a":"b"},"headers_add":{"aa": ["bb","cc"]}}
headers_remove
: remove the header.
headers_add
: append to the header instead of overwrite it.
headers
: set the header.
alb.ingress.cpaas.io/rewrite-response: |
{"headers_remove":["h1"],"headers":{"a":"b"},"headers_add":{"aa": ["bb","cc"]}}
headers_remove
: remove the header.
headers_add
: append to the header instead of overwrite it.
headers
: set the header.
nginx.ingress.kubernetes.io/rewrite-target
nginx.ingress.kubernetes.io/enable-cors
nginx.ingress.kubernetes.io/cors-allow-headers
nginx.ingress.kubernetes.io/cors-allow-origin
nginx.ingress.kubernetes.io/backend-protocol
nginx.ingress.kubernetes.io/temporal-redirect
nginx.ingress.kubernetes.io/permanent-redirect
nginx.ingress.kubernetes.io/upstream-vhost
By default, ALB is deployed as a host network, which has the advantage of direct access via node ip, and the disadvantage that each ALB can only have exclusive access to the node, or you need to manually manage the ALB's ports. But, ALB also supports container network mode deployment and provides external access through Loadbalancer type Service.
apiVersion: crd.alauda.io/v2beta1
kind: ALB2
metadata:
name: alb-demo
namespace: kube-system
spec:
type: "nginx"
config:
networkMode: container # use container networkmode
vip:
enableLbSvc: true # automatically creates a Service of type LoadBalancer and treats the address assigned to the Service as the address of the ALB
loadbalancerName: alb-demo
nodeSelector:
alb-demo: "true"
projects:
- ALL_ALL
replicas: 1
ALB supports GatewayAPI(v0.6.2) out of box, just set the gatewayClassName
to exclusive-gateway
when creating gateways. GatewayAPI 1.0 support is on the way.
apiVersion: gateway.networking.k8s.io/v1beta1
kind: Gateway
metadata:
name: g1
namespace: g1
spec:
gatewayClassName: exclusive-gateway
listeners:
- name: http
port: 80
protocol: HTTP
allowedRoutes:
namespaces:
from: All