Update start script to wait for ipamd health

Wait for the ipamd health check to be SERVING before copying in the CNI
binary and config file. #282

scripts/install-aws.sh

@@ -1,14 +1,42 @@
 #!/usr/bin/env bash
-echo "===== Starting installing AWS-CNI ========="
-sed -i s/__VETHPREFIX__/${AWS_VPC_K8S_CNI_VETHPREFIX:-"eni"}/g /app/10-aws.conflist
-cp /app/aws-cni /host/opt/cni/bin/
-cp /app/portmap /host/opt/cni/bin/
-cp /app/aws-cni-support.sh /host/opt/cni/bin/
-cp /app/10-aws.conflist /host/etc/cni/net.d/
-
-if [[ -f /host/etc/cni/net.d/aws.conf ]]; then
+
+grpcHealthCheck () {
+  /app/grpc_health_probe -addr 127.0.0.1:50051
+}
+
+waitIPamDServing () {
+   until grpcHealthCheck; do
+    echo "Waiting for ipamd health check";
+    sleep 1;
+  done
+}
+
+main () {
+  # Remove old config files that might have been baked into older AMIs
+  if [[ -f /host/etc/cni/net.d/aws.conf ]]; then
     rm /host/etc/cni/net.d/aws.conf
-fi
+  fi
+
+  # Copy standard files
+  cp /app/aws-cni-support.sh /host/opt/cni/bin/
+  cp /app/portmap /host/opt/cni/bin/
+
+  echo "===== Starting amazon-k8s-agent ==========="
+  /app/aws-k8s-agent &
+
+  # Check ipamd health
+  echo "Checking if ipamd is serving"
+  waitIPamDServing
+
+  echo "===== Copying AWS CNI plugin and config ========="
+  sed -i s/__VETHPREFIX__/"${AWS_VPC_K8S_CNI_VETHPREFIX:-"eni"}"/g /app/10-aws.conflist
+  cp /app/aws-cni /host/opt/cni/bin/
+  cp /app/10-aws.conflist /host/etc/cni/net.d/
+
+  # Check that ipamd is healthy, exit if the check fails
+  while grpcHealthCheck; do
+      sleep 10;
+  done
+}
 
-echo "===== Starting amazon-k8s-agent ==========="
-/app/aws-k8s-agent
+main