Add notes on docker in gVisor support in GKE.

PiperOrigin-RevId: 844543592

Author: milantracy

g3doc/user_guide/tutorials/docker-in-gke-sandbox.md

@@ -6,6 +6,8 @@ applications.
 In gVisor, all basic docker commands should function as expected. The host
 network driver and the bridge network driver are tested and supported.
 
+> gVisor supports Docker Engine up to version 27 in GKE.
+
 ## How to run Docker in a GKE Sandbox
 
 ### GKE standard cluster
@@ -25,15 +27,15 @@ granted by the gVisor sandbox.
 An example command to start an GKE autopilot cluster will be:
 
 ```sh
-gcloud container clusters create-auto [CLUTER_NAME] --workload-policies=allow-net-admin --location=[LOCATION] --cluster-version=1.33.2-gke.4655000
+gcloud container clusters create-auto [CLUTER_NAME] --workload-policies=allow-net-admin --location=[LOCATION]
 ```
 
 ### Get started
 
 Prepare a container image with pre-installed Docker:
 
 ```shell
-$ docker build -t docker-in-gvisor images/basic/docker
+$ docker build -t docker-in-gvisor images/basic/docker/
 $ docker push {registry_url}/docker-in-gvisor:latest
 ```
 

g3doc/user_guide/tutorials/docker-in-gvisor.md

@@ -6,6 +6,8 @@ applications.
 In gVisor, all basic docker commands should function as expected. The host
 network driver and the bridge network driver are tested and supported.
 
+> gVisor supports Docker Engine up to version 28.
+
 ### NOTE on runsc setup
 
 To run docker within gvisor, runsc must be enabled to allow raw sockets. This is

images/basic/docker/Dockerfile

@@ -1,5 +1,6 @@
 FROM ubuntu:24.04
 
+ARG DOCKER_VERSION="5:27.5.1-1~ubuntu.24.04~noble"
 ENV DEBIAN_FRONTEND="noninteractive"
 RUN apt-get update && apt-get -y install ca-certificates curl
 # TODO(gvisor.dev/issue/11883): use the latest docker version.
@@ -8,7 +9,7 @@ RUN curl -fsSL https://download.docker.com/linux/ubuntu/gpg -o /etc/apt/keyrings
   echo "deb [arch=$(dpkg --print-architecture) signed-by=/etc/apt/keyrings/docker.asc] https://download.docker.com/linux/ubuntu \
   $(. /etc/os-release && echo "$VERSION_CODENAME") stable" > /etc/apt/sources.list.d/docker.list && \
   apt-get update && \
-  apt-get install -qqy docker-ce=5:28.5.2-1~ubuntu.24.04~noble docker-ce-cli=5:28.5.2-1~ubuntu.24.04~noble containerd.io docker-buildx-plugin docker-compose-plugin iproute2
+  apt-get install -qqy docker-ce=${DOCKER_VERSION} docker-ce-cli=${DOCKER_VERSION} containerd.io docker-buildx-plugin docker-compose-plugin iproute2
 
 COPY start-dockerd.sh .
 CMD /start-dockerd.sh