My Google Compute Engine startup script has CommunicationsLinkFailures (SQL State 08S01 Error 0) even though it runs fine locally? - mysql

Question

I'm deploying my Java8 SpringBoot App to a Google Compute Engine instance and trying to connect it to a Debian9 CloudSQL instance. I'm trying to get the instance to run with my startup-script.sh, but when it tries to boot up the SpringBoot Application, according to the daemon.log, when the .war is ran by "java -jar order-routing-0.0.1-SNAPSHOT.war" the startup fails with a "Unable to obtain connection from database: Communications link failure", with SQL State:08S01 and error code 0.
I mapped the GCE instance to a static external IP, as well as whitelisting that IP on the CloudSQL instance's connections configs. I also verify that the war file runs locally with "java -jar order-routing.war".
Here is my startup script.sh:
#!/usr/bin/env bash
# This script is passed to the GCE instance by the setup script. It is run on the instance when it is spun up.
# Derived from GCE Tutorial at https://cloud.google.com/java/docs/tutorials/bookshelf-on-compute-engine
# [START script]
set -e
set -v
# Talk to the metadata server to get the project id
PROJECTID=$(curl -s "http://metadata.google.internal/computeMetadata/v1/project/project-id" -H "Metadata-Flavor: Google")
BUCKET=$(curl -s "http://metadata.google.internal/computeMetadata/v1/instance/attributes/BUCKET" -H "Metadata-Flavor: Google")
echo "Project ID: ${PROJECTID}"
# get our file(s)
gsutil cp "gs://order-routing-install/gce/"** .
# Install dependencies from apt
apt-get update
apt-get install mysql-client -y
wget https://dl.google.com/cloudsql/cloud_sql_proxy.linux.amd64
mv cloud_sql_proxy.linux.amd64 cloud_sql_proxy
chmod +x cloud_sql_proxy
./cloud_sql_proxy -instances=instance-qa1:us-central1:instance-qa1-cloudsql-0=tcp:3307 &
apt-get install -yq default-jre
apt-get install -yq default-jdk
java -jar order-routing-0.0.1-SNAPSHOT.war
# [END script]
Here is the failing error log from the daemon.log:
ConfigServletWebServerApplicationContext : Exception encountered during context initialization - cancelling refresh attempt: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'flywayInitializer' defined in class path resource [org/springframework/boot/autoconfigure/flyway/FlywayAutoConfiguration$FlywayConfiguration.class]: Invocation of init method failed; nested exception is org.flywaydb.core.internal.exception.FlywaySqlException:
Jul 29 03:39:30 order-routing-group-hk66 startup-script: INFO startup-script: Unable to obtain connection from database: Communications link failure
Jul 29 03:39:30 order-routing-group-hk66 startup-script: INFO startup-script: 2019-07-29 03:39:30.435 INFO 9051 --- [ main] ConditionEvaluationReportLoggingListener :
Jul 29 03:39:30 order-routing-group-hk66 startup-script: INFO startup-script:n from database: Communications link failure
Jul 29 03:39:30 order-routing-group-hk66 startup-script: INFO startup-script: The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.
Jul 29 03:39:30 order-routing-group-hk66 startup-script: INFO startup-script: SQL State : 08S01
Jul 29 03:39:30 order-routing-group-hk66 startup-script: INFO startup-script: Error Code : 0
Jul 29 03:39:30 order-routing-group-hk66 startup-script: INFO startup-script: Message : Communications link failure
Expected Result:
The GCE instance starts up the war file successfully and I can access my app using the external IP.
Actual Result:
Getting CommunicationsLinkFailures upon starting up Spring Boot Java app.