assign-lb-ip
Assigns loadBalancerIP
address to a Kubernetes
service for testing purposes.
This is normally done by the cloud provider or the
metallb "controller". It is
not possible to set the Status.loadBalancer.Ingress
with kubectl
(AFAIK), so this utility is needed.
Usage
Dual-stack phase 3 released in K8s v1.20 (alpha) is assumed.
Use assign-lb-ip -help
to get a brief help printout.
The easiest way is to define the loadBalancerIP
in the service
manifest;
apiVersion: v1
kind: Service
metadata:
name: mconnect-ipv6-lb
spec:
ipFamilies:
- IPv6
selector:
app: mconnect
ports:
- port: 5001
type: LoadBalancer
loadBalancerIP: 1000::8
The EXTERNAL-IP will still be in <pending>
but you can now simply
run assign-lb-ip
to set it. Example;
$ kubectl get svc mconnect-ipv6-lb
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
mconnect-ipv6-lb LoadBalancer fd00:4000::250b <pending> 5001:32030/TCP 5m5s
$ assign-lb-ip -svc mconnect-ipv6-lb
$ kubectl get svc mconnect-ipv6-lb
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
mconnect-ipv6-lb LoadBalancer fd00:4000::250b 1000::8 5001:32030/TCP 5m36s
assign-lb-ip
will take the loadBalancerIP
you specified in the
manifest and set it as the "real" load-balancer IP.
You can also explicitly specify the load-balancer IP using the -ip
option.
The service must have type: LoadBalancer
and an explicitly specified
-ip
must work with net.ParseIP()
. Other than that no checks are
made.
You can also define a dual-stack service;
apiVersion: v1
kind: Service
metadata:
name: mserver-preferdual-lb
spec:
ipFamilyPolicy: PreferDualStack
selector:
app: mserver
ports:
- port: 5001
type: LoadBalancer
Here PreferDualStack
means that the service will be dual-stack if
deployed in a dual-stack cluster. The "loadBalancerIP" field can not
be used but a new loadBalancerIPs
fiels is proposed
(PR).
For dual-stack services a comma separated list of ip's is specified;
$ assign-lb-ip -svc mserver-preferdual-lb -ip 10.0.0.2,1000::2
$ kubectl get svc mserver-preferdual-lb
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
mserver-preferdual-lb LoadBalancer 12.0.22.230 10.0.0.2,1000::2 5001:31686/TCP,5003:31406/TCP 2m16s
Use the -clear
option to remove LoadBalancerIPs.
Older dual-stack versions
Before K8s v1.20.0 only single-stack services could be specified but
for both families. Syntax is sligtly different but assign-lb-ip
works the same way.
apiVersion: v1
kind: Service
metadata:
name: mconnect-ipv6-lb
spec:
ipFamily: IPv6
selector:
app: mconnect
ports:
- port: 5001
type: LoadBalancer
loadBalancerIP: 1000::8
Build
GO111MODULE=on CGO_ENABLED=0 GOOS=linux go build -o assign-lb-ip \
-ldflags "-extldflags '-static' -X main.version=$(git describe --dirty --tags)" \
./cmd/...