feat: customization of exposed service ports

Problem: when deploying usernetes in a multi
tenant environment, there will likely be clashing
of ports due to their hard coding of traditional
values.
Solution: expose these ports (those mapped to the
host in the docker-compose.yaml and kubeadm-config
yaml as environment variables to customize.

Signed-off-by: vsoch <[email protected]>

Makefile

@@ -5,6 +5,12 @@ HOSTNAME ?= $(shell hostname)
 # HOSTNAME is the name of the physical host
 export HOSTNAME := $(HOSTNAME)
 
+# Exposed ports to the host (default to same as in container)
+export U7S_EXPOSED_PORT_ETCD ?= 2379
+export U7S_EXPOSED_PORT_KUBE_APISERVER ?= 6443
+export U7S_EXPOSED_PORT_KUBELET ?= 10250
+export U7S_EXPOSED_PORT_FLANNEL ?= 8472
+
 HOST_IP ?= $(shell ip --json route get 1 | jq -r .[0].prefsrc)
 NODE_NAME ?= u7s-$(HOSTNAME)
 NODE_SUBNET ?= $(shell $(CURDIR)/Makefile.d/node-subnet.sh)
@@ -34,6 +40,7 @@ NODE_SHELL := $(COMPOSE) exec \
 	-e U7S_NODE_NAME=$(U7S_NODE_NAME) \
 	-e U7S_NODE_SUBNET=$(U7S_NODE_SUBNET) \
 	-e U7S_NODE_IP=$(U7S_NODE_IP) \
+	-e U7S_EXPOSED_PORT_KUBE_APISERVER=$(U7S_EXPOSED_PORT_KUBE_APISERVER) \
 	$(NODE_SERVICE_NAME)
 
 ifeq ($(CONTAINER_ENGINE),nerdctl)

docker-compose.yaml

@@ -12,13 +12,13 @@ services:
         ipv4_address: ${U7S_NODE_IP}
     ports:
       # etcd
-      - 2379:2379
+      - ${U7S_EXPOSED_PORT_ETCD}:2379
       # kube-apiserver
-      - 6443:6443
+      - ${U7S_EXPOSED_PORT_KUBE_APISERVER}:6443
       # kubelet
-      - 10250:10250
+      - ${U7S_EXPOSED_PORT_KUBELET}:10250
       # flannel
-      - 8472:8472/udp
+      - ${U7S_EXPOSED_PORT_FLANNEL}:8472/udp
     volumes:
       - .:/usernetes:ro
       - /boot:/boot:ro

kubeadm-config.yaml

@@ -7,7 +7,7 @@ kind: ClusterConfiguration
 networking:
   serviceSubnet: "10.96.0.0/16"
   podSubnet: "10.244.0.0/16"
-controlPlaneEndpoint: "${U7S_NODE_NAME}:6443"
+controlPlaneEndpoint: "${U7S_NODE_NAME}:${U7S_EXPOSED_PORT_KUBE_APISERVER}"
 apiServer:
   extraArgs:
     advertise-address: "${U7S_HOST_IP}"