From 3541a93f92ff061d8d9df458d6f20bed6af9ecd3 Mon Sep 17 00:00:00 2001
From: Alan Grosskurth <grosskur@google.com>
Date: Thu, 10 May 2018 18:23:09 -0700
Subject: [PATCH] gce: Prefer MASTER_ADVERTISE_ADDRESS in apiserver setup

MASTER_ADVERTISE_ADDRESS is used to set the --advertise-address flag
for the apiserver. It's useful for running the apiserver behind a load
balancer.

However, if PROJECT_ID, TOKEN_URL, TOKEN_BODY, and NODE_NETWORK are
all set, the GCE VM's external IP address will be fetched and used
instead and MASTER_ADVERTISE_ADDRESS will be ignored.

Change this behavior so that MASTER_ADVERTISE_ADDRESS takes precedence
because it's more specific. We still fall back to using the VM's
external IP address if the other variables are set.

Also: Pass --ssh-user and --ssh-keyfile flags if both PROXY_SSH_USER
and MASTER_ADVERTISE_ADDRESS is set.
---
 cluster/gce/gci/configure-helper.sh | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/cluster/gce/gci/configure-helper.sh b/cluster/gce/gci/configure-helper.sh
index 71db85f2759..59b7bc1172a 100644
--- a/cluster/gce/gci/configure-helper.sh
+++ b/cluster/gce/gci/configure-helper.sh
@@ -1622,15 +1622,19 @@ function start-kube-apiserver {
   if [[ -n "${FEATURE_GATES:-}" ]]; then
     params+=" --feature-gates=${FEATURE_GATES}"
   fi
-  if [[ -n "${PROJECT_ID:-}" && -n "${TOKEN_URL:-}" && -n "${TOKEN_BODY:-}" && -n "${NODE_NETWORK:-}" ]]; then
+  if [[ -n "${MASTER_ADVERTISE_ADDRESS:-}" ]]; then
+    params+=" --advertise-address=${MASTER_ADVERTISE_ADDRESS}"
+    if [[ -n "${PROXY_SSH_USER:-}" ]]; then
+      params+=" --ssh-user=${PROXY_SSH_USER}"
+      params+=" --ssh-keyfile=/etc/srv/sshproxy/.sshkeyfile"
+    fi
+  elif [[ -n "${PROJECT_ID:-}" && -n "${TOKEN_URL:-}" && -n "${TOKEN_BODY:-}" && -n "${NODE_NETWORK:-}" ]]; then
     local -r vm_external_ip=$(get-metadata-value "instance/network-interfaces/0/access-configs/0/external-ip")
     if [[ -n "${PROXY_SSH_USER:-}" ]]; then
       params+=" --advertise-address=${vm_external_ip}"
       params+=" --ssh-user=${PROXY_SSH_USER}"
       params+=" --ssh-keyfile=/etc/srv/sshproxy/.sshkeyfile"
     fi
-  elif [ -n "${MASTER_ADVERTISE_ADDRESS:-}" ]; then
-    params="${params} --advertise-address=${MASTER_ADVERTISE_ADDRESS}"
   fi
 
   local webhook_authn_config_mount=""