Allow setting the cluster prefix (to have foo1, foo2, etc. instead of node1, node2, etc.)

prepare-vms/lib/commands.sh

@@ -74,10 +74,10 @@ _cmd_deploy() {
     pssh -I sudo tee /usr/local/bin/docker-prompt <lib/docker-prompt
     pssh sudo chmod +x /usr/local/bin/docker-prompt
 
-    # If /home/docker/.ssh/id_rsa doesn't exist, copy it from node1
+    # If /home/docker/.ssh/id_rsa doesn't exist, copy it from the first node
     pssh "
     sudo -u docker [ -f /home/docker/.ssh/id_rsa ] ||
-    ssh -o StrictHostKeyChecking=no node1 sudo -u docker tar -C /home/docker -cvf- .ssh |
+    ssh -o StrictHostKeyChecking=no \$(cat /etc/name_of_first_node) sudo -u docker tar -C /home/docker -cvf- .ssh |
     sudo -u docker tar -C /home/docker -xf-"
 
     # if 'docker@' doesn't appear in /home/docker/.ssh/authorized_keys, copy it there
@@ -86,11 +86,11 @@ _cmd_deploy() {
     cat /home/docker/.ssh/id_rsa.pub |
     sudo -u docker tee -a /home/docker/.ssh/authorized_keys"
 
-    # On node1, create and deploy TLS certs using Docker Machine
+    # On the first node, create and deploy TLS certs using Docker Machine
     # (Currently disabled.)
     true || pssh "
-    if grep -q node1 /tmp/node; then
-        grep ' node' /etc/hosts | 
+    if i_am_first_node; then
+        grep '[0-9]\$' /etc/hosts |
         xargs -n2 sudo -H -u docker \
         docker-machine create -d generic --generic-ssh-user docker --generic-ip-address
     fi"
@@ -139,6 +139,7 @@ _cmd_kube() {
     TAG=$1
     need_tag
 
+    # Optional version, e.g. 1.13.5
     KUBEVERSION=$2
     if [ "$KUBEVERSION" ]; then
         EXTRA_KUBELET="=$KUBEVERSION-00"
@@ -161,14 +162,14 @@ _cmd_kube() {
 
     # Initialize kube master
     pssh --timeout 200 "
-    if grep -q node1 /tmp/node && [ ! -f /etc/kubernetes/admin.conf ]; then
+    if i_am_first_node && [ ! -f /etc/kubernetes/admin.conf ]; then
         kubeadm token generate > /tmp/token &&
 	sudo kubeadm init $EXTRA_KUBEADM --token \$(cat /tmp/token) --apiserver-cert-extra-sans \$(cat /tmp/ipv4)
     fi"
 
     # Put kubeconfig in ubuntu's and docker's accounts
     pssh "
-    if grep -q node1 /tmp/node; then
+    if i_am_first_node; then
         sudo mkdir -p \$HOME/.kube /home/docker/.kube &&
         sudo cp /etc/kubernetes/admin.conf \$HOME/.kube/config &&
         sudo cp /etc/kubernetes/admin.conf /home/docker/.kube/config &&
@@ -178,21 +179,22 @@ _cmd_kube() {
 
     # Install weave as the pod network
     pssh "
-    if grep -q node1 /tmp/node; then
+    if i_am_first_node; then
         kubever=\$(kubectl version | base64 | tr -d '\n') &&
         kubectl apply -f https://cloud.weave.works/k8s/net?k8s-version=\$kubever
     fi"
 
     # Join the other nodes to the cluster
     pssh --timeout 200 "
-    if ! grep -q node1 /tmp/node && [ ! -f /etc/kubernetes/kubelet.conf ]; then
-        TOKEN=\$(ssh -o StrictHostKeyChecking=no node1 cat /tmp/token) &&
-        sudo kubeadm join --discovery-token-unsafe-skip-ca-verification --token \$TOKEN node1:6443
+    if ! i_am_first_node && [ ! -f /etc/kubernetes/kubelet.conf ]; then
+        FIRSTNODE=\$(cat /etc/name_of_first_node) &&
+        TOKEN=\$(ssh -o StrictHostKeyChecking=no \$FIRSTNODE cat /tmp/token) &&
+        sudo kubeadm join --discovery-token-unsafe-skip-ca-verification --token \$TOKEN \$FIRSTNODE:6443
     fi"
 
     # Install metrics server
     pssh "
-    if grep -q node1 /tmp/node; then
+    if i_am_first_node; then
 	kubectl apply -f https://raw.githubusercontent.com/jpetazzo/container.training/master/k8s/metrics-server.yaml
     fi"
 
@@ -256,10 +258,9 @@ _cmd_kubetest() {
     # Feel free to make that better ♥
     pssh "
     set -e
-    [ -f /tmp/node ]
-    if grep -q node1 /tmp/node; then
+    if i_am_first_node; then
       which kubectl
-      for NODE in \$(awk /\ node/\ {print\ \\\$2} /etc/hosts); do
+      for NODE in \$(awk /[0-9]\$/\ {print\ \\\$2} /etc/hosts); do
         echo \$NODE ; kubectl get nodes | grep -w \$NODE | grep -w Ready
       done
     fi"
@@ -383,7 +384,7 @@ _cmd_start() {
         *) die "Unrecognized parameter: $1."
         esac
     done
-    
+
     if [ -z "$INFRA" ]; then
         die "Please add --infra flag to specify which infrastructure file to use."
     fi
@@ -394,8 +395,8 @@ _cmd_start() {
         COUNT=$(awk '/^clustersize:/ {print $2}' $SETTINGS)
         warning "No --count option was specified. Using value from settings file ($COUNT)."
     fi
-    
-    # Check that the specified settings and infrastructure are valid.        
+
+    # Check that the specified settings and infrastructure are valid.
     need_settings $SETTINGS
     need_infra $INFRA
 
@@ -467,7 +468,7 @@ _cmd_helmprom() {
     TAG=$1
     need_tag
     pssh "
-    if grep -q node1 /tmp/node; then
+    if i_am_first_node; then
         kubectl -n kube-system get serviceaccount helm ||
             kubectl -n kube-system create serviceaccount helm
         helm init --service-account helm
@@ -557,8 +558,8 @@ test_vm() {
     for cmd in "hostname" \
         "whoami" \
         "hostname -i" \
-        "cat /tmp/node" \
-        "cat /tmp/ipv4" \
+        "ls -l /usr/local/bin/i_am_first_node" \
+        "grep . /etc/name_of_first_node /etc/ipv4_of_first_node" \
         "cat /etc/hosts" \
         "hostnamectl status" \
         "docker version | grep Version -B1" \

prepare-vms/lib/postprep.py

@@ -12,6 +12,7 @@ config = yaml.load(open("/tmp/settings.yaml"))
 COMPOSE_VERSION = config["compose_version"]
 MACHINE_VERSION = config["machine_version"]
 CLUSTER_SIZE = config["clustersize"]
+CLUSTER_PREFIX = config["clusterprefix"]
 ENGINE_VERSION = config["engine_version"]
 DOCKER_USER_PASSWORD = config["docker_user_password"]
 
@@ -121,7 +122,7 @@ addresses = list(l.strip() for l in sys.stdin)
 assert ipv4 in addresses
 
 def makenames(addrs):
-    return [ "node%s"%(i+1) for i in range(len(addrs)) ]
+    return [ "%s%s"%(CLUSTER_PREFIX, i+1) for i in range(len(addrs)) ]
 
 while addresses:
     cluster = addresses[:CLUSTER_SIZE]
@@ -135,15 +136,21 @@ while addresses:
     print(cluster)
 
     mynode = cluster.index(ipv4) + 1
-    system("echo node{} | sudo -u docker tee /tmp/node".format(mynode))
-    system("echo node{} | sudo tee /etc/hostname".format(mynode))
-    system("sudo hostname node{}".format(mynode))
+    system("echo {}{} | sudo tee /etc/hostname".format(CLUSTER_PREFIX, mynode))
+    system("sudo hostname {}{}".format(CLUSTER_PREFIX, mynode))
     system("sudo -u docker mkdir -p /home/docker/.ssh")
     system("sudo -u docker touch /home/docker/.ssh/authorized_keys")
 
+    # Create a convenience file to easily check if we're the first node
     if ipv4 == cluster[0]:
-        # If I'm node1 and don't have a private key, generate one (with empty passphrase)
+        system("sudo ln -sf /bin/true /usr/local/bin/i_am_first_node")
+        # On the first node, if we don't have a private key, generate one (with empty passphrase)
         system("sudo -u docker [ -f /home/docker/.ssh/id_rsa ] || sudo -u docker ssh-keygen -t rsa -f /home/docker/.ssh/id_rsa -P ''")
+    else:
+        system("sudo ln -sf /bin/false /usr/local/bin/i_am_first_node")
+    # Record the IPV4 and name of the first node
+    system("echo {} | sudo tee /etc/ipv4_of_first_node".format(cluster[0]))
+    system("echo {} | sudo tee /etc/name_of_first_node".format(names[0]))
 
 FINISH = time.time()
 duration = "Initial deployment took {}s".format(str(FINISH - START)[:5])

prepare-vms/settings/csv.yaml

@@ -1,5 +1,8 @@
 # Number of VMs per cluster
 clustersize: 5
 
+# The hostname of each node will be clusterprefix + a number
+clusterprefix: node
+
 # Jinja2 template to use to generate ready-to-cut cards
 cards_template: clusters.csv

prepare-vms/settings/enix.yaml

@@ -1,6 +1,9 @@
 # Number of VMs per cluster
 clustersize: 1
 
+# The hostname of each node will be clusterprefix + a number
+clusterprefix: node
+
 # Jinja2 template to use to generate ready-to-cut cards
 cards_template: enix.html
 

prepare-vms/settings/example.yaml

@@ -3,6 +3,9 @@
 # Number of VMs per cluster
 clustersize: 5
 
+# The hostname of each node will be clusterprefix + a number
+clusterprefix: node
+
 # Jinja2 template to use to generate ready-to-cut cards
 cards_template: cards.html
 

prepare-vms/settings/fundamentals.yaml

@@ -3,6 +3,9 @@
 # Number of VMs per cluster
 clustersize: 1
 
+# The hostname of each node will be clusterprefix + a number
+clusterprefix: node
+
 # Jinja2 template to use to generate ready-to-cut cards
 cards_template: cards.html
 

prepare-vms/settings/jerome.yaml

@@ -1,6 +1,9 @@
 # Number of VMs per cluster
 clustersize: 4
 
+# The hostname of each node will be clusterprefix + a number
+clusterprefix: node
+
 # Jinja2 template to use to generate ready-to-cut cards
 cards_template: jerome.html
 

prepare-vms/settings/kube101.yaml

@@ -3,6 +3,9 @@
 # Number of VMs per cluster
 clustersize: 3
 
+# The hostname of each node will be clusterprefix + a number
+clusterprefix: node
+
 # Jinja2 template to use to generate ready-to-cut cards
 cards_template: kube101.html
 

prepare-vms/settings/swarm.yaml

@@ -3,6 +3,9 @@
 # Number of VMs per cluster
 clustersize: 3
 
+# The hostname of each node will be clusterprefix + a number
+clusterprefix: node
+
 # Jinja2 template to use to generate ready-to-cut cards
 cards_template: cards.html