Google Compute Engine: Floating IP?

Posting my comment as an answer for other users looking at this thread:

Support for Virtual IP/Floating IP in GCE is currently not available. Feature request is already created. You can refer to this link to subscribe for the updates. The workaround for now would be to use the GCE Load balancer

Google recently changed and allowed the use of floating IP's and this is described..

The solution comes down to the 2 lines of code below at the end between ----- and -----, not accounting for the creation of the ip-fallover network where you will launch your instances

#!/bin/bash
export CLOUDSDK_PYTHON=/opt/rh/python27/root/usr/bin/python2.7
export PATH=/opt/rh/python27/root/usr/bin:$PATH
export token=$(gcloud auth print-identity-token)
export instance_name=$(curl -H "Authorization: Bearer $token" -s -H "Metadata-Flavor: Google" "http://metadata.google.internal/computeMetadata/v1/instance/name")
export instance_zone=$(curl -H "Authorization: Bearer $token" -s -H "Metadata-Flavor: Google" "http://metadata.google.internal/computeMetadata/v1/instance/zone" | awk -F '/' '{ print $NF }')

export vip=10.11.12.13/32 
ip ad del $vip dev eth0

gcloud compute routes delete floating --quiet

gcloud compute routes create floating  --destination-range $vip --network ip-failover --priority 500 --next-hop-instance-zone $instance_zone --next-hop-instance $instance_name --quiet
ip ad ad $vip dev eth0

For a more complete walk through of what needs to be done, look at option 4 of the link below.
https://cloud.google.com/solutions/best-practices-floating-ip-addresses