This guide explains how to downgrade Anthos Service Mesh from 1.6.14 to 1.5.10 on Anthos clusters on VMware.
Redeploying the Anthos Service Mesh control plane components takes about 5 to 10 minutes to complete. Additionally, you need to inject new sidecar proxies in all of your workloads so they are updated with the current Anthos Service Mesh version. The time it takes to update the sidecar proxies depends on many factors, such as the number of pods, the number of nodes, deployment scaling settings, pod disruption budgets, and other configuration settings. A rough estimate of the time that it takes to update the sidecar proxies is 100 pods per minute.
Overview of the downgrade
This section outlines the steps that you take to downgrade Anthos Service Mesh.
Prepare
Review the Supported features and this guide to become familiar with the features and the downgrade process.
If you enabled optional features when you installed the previous version of Anthos Service Mesh, you need to enable the same features when you downgrade. You enable optional features by adding
--set values
flags or by specifying the-f
flag with a YAML file when you run theistioctl install
command.
Downgrade
Follow the steps in this guide to prepare for downgrading Anthos Service Mesh.
Test your application to verify that the workloads are working correctly.
Setting up your environment
You need the following tools on the machine you want to install Anthos Service Mesh from. Note that you can install Anthos Service Mesh only on a user cluster, not an admin cluster.
- The
curl
command-line tool. - The Google Cloud CLI.
After installing the Google Cloud CLI:
Authenticate with the Google Cloud CLI:
gcloud auth login
Update the components:
gcloud components update
Install
kubectl
:gcloud components install kubectl
Install the required version of
kpt
:curl -L https://github.com/GoogleContainerTools/kpt/releases/download/v0.39.2/kpt_linux_amd64 > kpt_0_39_2 chmod +x kpt_0_39_2 alias kpt="$(readlink -f kpt_0_39_2)"
Switch context to your user cluster:
kubectl config use-context CLUSTER_NAME
Grant cluster admin permissions to your user account (your Google Cloud login email address). You need these permissions to create the necessary role based access control (RBAC) rules for Anthos Service Mesh:
kubectl create clusterrolebinding cluster-admin-binding \ --clusterrole=cluster-admin \ --user=USER_ACCOUNT
Downloading the installation file
-
Download the Anthos Service Mesh installation file to your current working
directory:
curl -LO https://storage.googleapis.com/gke-release/asm/istio-1.5.10-asm.2-linux.tar.gz
-
Download the signature file and use
openssl
to verify the signature:curl -LO https://storage.googleapis.com/gke-release/asm/istio-1.5.10-asm.2-linux.tar.gz.1.sig openssl dgst -verify /dev/stdin -signature istio-1.5.10-asm.2-linux.tar.gz.1.sig istio-1.5.10-asm.2-linux.tar.gz <<'EOF' -----BEGIN PUBLIC KEY----- MFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgAEWZrGCUaJJr1H8a36sG4UUoXvlXvZ wQfk16sxprI2gOJ2vFFggdq3ixF2h4qNBt0kI7ciDhgpwS8t+/960IsIgw== -----END PUBLIC KEY----- EOF
The expected output is:
Verified OK
-
Extract the contents of the file to any location on your file system. For
example, to extract the contents to the current working directory:
tar xzf istio-1.5.10-asm.2-linux.tar.gz
The command creates an installation directory in your current working directory named
istio-1.5.10-asm.2
that contains:- Sample applications in the
samples
directory. - The
istioctl
command-line tool that you use to install Anthos Service Mesh is in thebin
directory. - The Anthos Service Mesh configuration profiles are in the
manifests/profiles
directory.
- Sample applications in the
-
Download the Anthos Service Mesh installation file to your current working
directory:
curl -LO https://storage.googleapis.com/gke-release/asm/istio-1.5.10-asm.2-osx.tar.gz
-
Download the signature file and use
openssl
to verify the signature:curl -LO https://storage.googleapis.com/gke-release/asm/istio-1.5.10-asm.2-osx.tar.gz.1.sig openssl dgst -sha256 -verify /dev/stdin -signature istio-1.5.10-asm.2-osx.tar.gz.1.sig istio-1.5.10-asm.2-osx.tar.gz <<'EOF' -----BEGIN PUBLIC KEY----- MFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgAEWZrGCUaJJr1H8a36sG4UUoXvlXvZ wQfk16sxprI2gOJ2vFFggdq3ixF2h4qNBt0kI7ciDhgpwS8t+/960IsIgw== -----END PUBLIC KEY----- EOF
The expected output is:
Verified OK
-
Extract the contents of the file to any location on your file system. For
example, to extract the contents to the current working directory:
tar xzf istio-1.5.10-asm.2-osx.tar.gz
The command creates an installation directory in your current working directory named
istio-1.5.10-asm.2
that contains:- Sample applications in the
samples
directory. - The
istioctl
command-line tool that you use to install Anthos Service Mesh is in thebin
directory. - The Anthos Service Mesh configuration profiles are in the
manifests/profiles
directory.
- Sample applications in the
-
Download the Anthos Service Mesh installation file to your current working
directory:
curl -LO https://storage.googleapis.com/gke-release/asm/istio-1.5.10-asm.2-win.zip
-
Download the signature file and use
openssl
to verify the signature:curl -LO https://storage.googleapis.com/gke-release/asm/istio-1.5.10-asm.2-win.zip.1.sig openssl dgst -verify - -signature istio-1.5.10-asm.2-win.zip.1.sig istio-1.5.10-asm.2-win.zip <<'EOF' -----BEGIN PUBLIC KEY----- MFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgAEWZrGCUaJJr1H8a36sG4UUoXvlXvZ wQfk16sxprI2gOJ2vFFggdq3ixF2h4qNBt0kI7ciDhgpwS8t+/960IsIgw== -----END PUBLIC KEY----- EOF
The expected output is:
Verified OK
-
Extract the contents of the file to any location on your file system. For
example, to extract the contents to the current working directory:
tar xzf istio-1.5.10-asm.2-win.zip
The command creates an installation directory in your current working directory named
istio-1.5.10-asm.2
that contains:- Sample applications in the
samples
directory. - The
istioctl
command-line tool that you use to install Anthos Service Mesh is in thebin
directory. - The Anthos Service Mesh configuration profiles are in the
manifests/profiles
directory.
- Sample applications in the
-
Ensure that you're in the Anthos Service Mesh installation's root directory.
cd istio-1.5.10-asm.2
-
For convenience, add the tools in the
/bin
directory to your PATH:export PATH=$PWD/bin:$PATH
Linux
Mac OS
Windows
Downgrading Anthos Service Mesh
To downgrade Anthos Service Mesh:
istioctl install --set profile=asm-multicloud
Check the control plane components
Downgrading requires reinstalling the control plane components, which takes
about 5 to 10 minutes to complete. The old control plane components are
terminated and then deleted as the new components are installed. You can check
the progress by looking at the value in the AGE
column of the workloads.
kubectl get pod -n istio-system
Example output:
NAME READY STATUS RESTARTS AGE istio-ingressgateway-5bfdf7c586-v6wxx 2/2 Terminating 0 25m istio-ingressgateway-7b598c5557-b88md 2/2 Running 0 5m44s istiod-78cdbbbdb-d7tps 1/1 Running 0 5m16s promsd-576b8db4d6-lqf64 2/2 Running 1 5m26s
In this example, there are two instances of istio-ingressgateway
. The
instance with 25m
in the AGE
column is being terminated. All the other
components are newly installed.
Updating sidecar proxies
Any workloads that were running on your cluster before the downgrade need to have the sidecar proxy re-injected so they have the current Anthos Service Mesh version.
With automatic sidecar injection, you can update the sidecars for existing Pods with a Pod restart. How you restart pods depends on if they were created as part of a Deployment.
If you used a Deployment, restart the Deployment, which restarts all Pods with sidecars:
kubectl rollout restart deployment -n YOUR_NAMESPACE
If you didn't use a Deployment, delete the Pods, and they are automatically recreated with sidecars:
kubectl delete pod -n YOUR_NAMESPACE --all
Check that all the Pods in the namespace have sidecars injected:
kubectl get pod -n YOUR_NAMESPACE
In the following example output from the previous command, notice that the
READY
column indicates there are two containers for each of your workloads: the primary container and the container for the sidecar proxy.NAME READY STATUS RESTARTS AGE YOUR_WORKLOAD 2/2 Running 0 20s ...