Migrating from Istio to Anthos Service Mesh

This page is part of a multi-page guide that explains how to migrate from Istio to Anthos Service Mesh version 1.8.6 on a GKE cluster for a mesh containing multiple clusters that are in different Google Cloud projects.

For migrations on a single-cluster mesh or for a mesh containing multiple clusters in the same Google Cloud project, refer to Installation, migration, and upgrade for GKE.

Before you begin

Before you install Anthos Service Mesh, make sure that you have:

Preparing for the migration

Be sure to review Preparing to migrate from Istio.

To migrate from Istio, you follow the revision upgrade process (referred to as "canary" upgrades in the Istio documentation). With a revision-based upgrade, you install a new revision of the control plane alongside the existing control plane. When you run istioctl install, you include an option to set a revision label that identifies the new control plane.

You then migrate to the new version by setting the same revision label on your workloads and performing a rolling restart to re-inject the proxies with the new Anthos Service Mesh version and configuration. With this approach, you can monitor the effect of the upgrade on a small percentage of your workloads. After testing your application, you can migrate all traffic to the new revision. This approach is much safer than doing an in-place upgrade where a new control plane immediately replaces the previous version of the control plane.

Setting credentials and permissions

  1. Initialize your project to ready it for installation. Among other things, this command creates a service account to let control plane components, such as the sidecar proxy, securely access your project's data and resources.

    curl --request POST \
      --header "Authorization: Bearer $(gcloud auth print-access-token)" \
      --data '' \
      "https://meshconfig.googleapis.com/v1alpha1/projects/${PROJECT_ID}:initialize"

    The command responds with empty curly braces: {}

  2. Get authentication credentials to interact with the cluster. This command also sets the current context for kubectl to the cluster.

    gcloud container clusters get-credentials ${CLUSTER_NAME} \
        --project=${PROJECT_ID}
    
  3. Grant cluster admin permissions to the current user. 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="$(gcloud config get-value core/account)"

If you see the "cluster-admin-binding" already exists error, you can safely ignore it and continue with the existing cluster-admin-binding.

Downloading the installation file

    Linux

  1. Download the Anthos Service Mesh installation file to your current working directory:
    curl -LO https://storage.googleapis.com/gke-release/asm/istio-1.8.6-asm.8-linux-amd64.tar.gz
  2. Download the signature file and use openssl to verify the signature:
    curl -LO https://storage.googleapis.com/gke-release/asm/istio-1.8.6-asm.8-linux-amd64.tar.gz.1.sig
    openssl dgst -verify /dev/stdin -signature istio-1.8.6-asm.8-linux-amd64.tar.gz.1.sig istio-1.8.6-asm.8-linux-amd64.tar.gz <<'EOF'
    -----BEGIN PUBLIC KEY-----
    MFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgAEWZrGCUaJJr1H8a36sG4UUoXvlXvZ
    wQfk16sxprI2gOJ2vFFggdq3ixF2h4qNBt0kI7ciDhgpwS8t+/960IsIgw==
    -----END PUBLIC KEY-----
    EOF

    The expected output is: Verified OK

  3. 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-1.8.6-asm.8-linux-amd64.tar.gz

    The command creates an installation directory in your current working directory named istio-1.8.6-asm.8 that contains:

    • Sample applications in the samples directory.
    • The istioctl command-line tool that you use to install Anthos Service Mesh is in the bin directory.
    • The Anthos Service Mesh configuration profiles are in the manifests/profiles directory.

  4. Ensure that you're in the Anthos Service Mesh installation's root directory.
    cd istio-1.8.6-asm.8
  5. Mac OS

  6. Download the Anthos Service Mesh installation file to your current working directory:
    curl -LO https://storage.googleapis.com/gke-release/asm/istio-1.8.6-asm.8-osx.tar.gz
  7. Download the signature file and use openssl to verify the signature:
    curl -LO https://storage.googleapis.com/gke-release/asm/istio-1.8.6-asm.8-osx.tar.gz.1.sig
    openssl dgst -sha256 -verify /dev/stdin -signature istio-1.8.6-asm.8-osx.tar.gz.1.sig istio-1.8.6-asm.8-osx.tar.gz <<'EOF'
    -----BEGIN PUBLIC KEY-----
    MFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgAEWZrGCUaJJr1H8a36sG4UUoXvlXvZ
    wQfk16sxprI2gOJ2vFFggdq3ixF2h4qNBt0kI7ciDhgpwS8t+/960IsIgw==
    -----END PUBLIC KEY-----
    EOF

    The expected output is: Verified OK

  8. 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-1.8.6-asm.8-osx.tar.gz

    The command creates an installation directory in your current working directory named istio-1.8.6-asm.8 that contains:

    • Sample applications in the samples directory.
    • The istioctl command-line tool that you use to install Anthos Service Mesh is in the bin directory.
    • The Anthos Service Mesh configuration profiles are in the manifests/profiles directory.

  9. Ensure that you're in the Anthos Service Mesh installation's root directory.
    cd istio-1.8.6-asm.8
  10. Windows

  11. Download the Anthos Service Mesh installation file to your current working directory:
    curl -LO https://storage.googleapis.com/gke-release/asm/istio-1.8.6-asm.8-win.zip
  12. Download the signature file and use openssl to verify the signature:
    curl -LO https://storage.googleapis.com/gke-release/asm/istio-1.8.6-asm.8-win.zip.1.sig
    openssl dgst -verify - -signature istio-1.8.6-asm.8-win.zip.1.sig istio-1.8.6-asm.8-win.zip <<'EOF'
    -----BEGIN PUBLIC KEY-----
    MFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgAEWZrGCUaJJr1H8a36sG4UUoXvlXvZ
    wQfk16sxprI2gOJ2vFFggdq3ixF2h4qNBt0kI7ciDhgpwS8t+/960IsIgw==
    -----END PUBLIC KEY-----
    EOF

    The expected output is: Verified OK

  13. 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-1.8.6-asm.8-win.zip

    The command creates an installation directory in your current working directory named istio-1.8.6-asm.8 that contains:

    • Sample applications in the samples directory.
    • The istioctl command-line tool that you use to install Anthos Service Mesh is in the bin directory.
    • The Anthos Service Mesh configuration profiles are in the manifests/profiles directory.

  14. Ensure that you're in the Anthos Service Mesh installation's root directory.
    cd istio-1.8.6-asm.8

Preparing resource configuration files

When you run the istioctl install command, you specify -f istio-operator.yaml on the command line. This file contains information about your project and cluster that Anthos Service Mesh requires. You need to download a package that contains istio-operator.yaml and other resource configuration files so that you can set the project and cluster information.

To prepare the resource configuration files:

Mesh CA

  1. Create a new directory for the Anthos Service Mesh package resource configuration files. We recommend that you use the cluster name as the directory name.

  2. Change to the directory where you want to download the Anthos Service Mesh package.

  3. Verify kpt version. Ensure you are running a pre 1.x version of kpt:

    kpt version
    

    The output should be similar to the following:

    0.39.2

    If you have kpt version 1.x or higher, see Setting up your environment to download the required version for your operating system.

  4. Download the package:

    kpt pkg get \
    https://github.com/GoogleCloudPlatform/anthos-service-mesh-packages.git/asm@release-1.8-asm asm
    
  5. Set the project ID for the project that the cluster was created in:

    kpt cfg set asm gcloud.core.project ${PROJECT_ID}
    
  6. Set the project number for the fleet host project:

    kpt cfg set asm gcloud.project.environProjectNumber ${FLEET_PROJECT_NUMBER}
    
  7. Set the cluster name:

    kpt cfg set asm gcloud.container.cluster ${CLUSTER_NAME}
    
  8. Set the default zone or region:

    kpt cfg set asm gcloud.compute.location ${CLUSTER_LOCATION}
    
  9. Set the tag to the version of Anthos Service Mesh that you are installing:

    kpt cfg set asm anthos.servicemesh.tag 1.8.6-asm.8
    
  10. Set the revision in Anthos Service Mesh package resource configuration files:

    kpt cfg set asm anthos.servicemesh.rev asm-186-8
    

    When you install Anthos Service Mesh, you set a revision label on istiod. You need to set the same revision on the validating webhook.

  11. Because the clusters in your multi-cluster configuration are in different projects, you need to configure the trust domain aliases for the other projects that will form the multi-cluster/multi-project service mesh.

    1. Get the project ID of all clusters that will be in the multi-cluster/multi-project mesh.

    2. For each cluster's project ID, set the trust domain aliases. For example, if you have clusters in 3 projects, run the following command and replace PROJECT_ID_1, PROJECT_ID_2, and PROJECT_ID_3 with each cluster's project ID.

      kpt cfg set asm anthos.servicemesh.trustDomainAliases PROJECT_ID_1.svc.id.goog PROJECT_ID_2.svc.id.goog PROJECT_ID_3.svc.id.goog

      As you configure the clusters in the other projects, you can use the same command.

      The trust domain aliases enables Mesh CA to authenticate workloads on clusters in other projects. In addition to setting the trust domain aliases, after installing Anthos Service Mesh, you have to enable cross-cluster load balancing.

  12. Output the values of the kpt setters:

    kpt cfg list-setters asm
    

    The output of the command is similar to the following:

                              NAME                                                       VALUE
    anthos.servicemesh.canonicalServiceHub               gke.gcr.io/asm/canonical-service-controller:1.8.6-asm.8
    anthos.servicemesh.controlplane.monitoring.enabled   true
    anthos.servicemesh.hub                               gke.gcr.io/asm
    anthos.servicemesh.hubMembershipID                   MEMBERSHIP_ID
    anthos.servicemesh.tag                               1.8.6-asm.8
    anthos.servicemesh.trustDomainAliases                [example-project-12345.svc.id.goog,example-project-23456.svc.id.goog,example-project-98765.svc.id.goog]
    base-dir                                             base
    gcloud.compute.location                              us-central
    gcloud.compute.network                               default
    gcloud.compute.subnetwork                            default
    gcloud.container.cluster                             example-cluster-1
    gcloud.container.cluster.clusterSecondaryRange
    gcloud.container.cluster.releaseChannel              REGULAR
    gcloud.container.cluster.servicesSecondaryRange
    gcloud.container.nodepool.max-nodes                  4
    gcloud.core.project                                  example-project-12345
    gcloud.project.environProjectID                      FLEET_PROJECT_ID
    gcloud.project.environProjectNumber                  1234567890123
    gcloud.project.projectNumber                         9876543210987

    Verify that the values for the following setters are correct:

    • anthos.servicemesh.rev
    • anthos.servicemesh.tag
    • anthos.servicemesh.trustDomainAliases
    • gcloud.compute.location
    • gcloud.container.cluster
    • gcloud.core.project
    • gcloud.project.environProjectNumber

    You can ignore the values for the other setters.

Istio CA

  1. Create a new directory for the Anthos Service Mesh package resource configuration files. We recommend that you use the cluster name as the directory name.

  2. Change to the directory where you want to download the Anthos Service Mesh package.

  3. Verify kpt version. Ensure you are running a pre 1.x version of kpt:

    kpt version
    

    The output should be similar to the following:

    0.39.2

    If you have kpt version 1.x or higher, download the required version:

    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)"
    
  4. Download the package:

    kpt pkg get \
    https://github.com/GoogleCloudPlatform/anthos-service-mesh-packages.git/asm@release-1.8-asm asm
    
  5. Set the project ID for the project that the cluster was created in:

    kpt cfg set asm gcloud.core.project ${PROJECT_ID}
    
  6. Set the project number for the fleet host project:

    kpt cfg set asm gcloud.project.environProjectNumber ${FLEET_PROJECT_NUMBER}
    
  7. Set the cluster name:

    kpt cfg set asm gcloud.container.cluster ${CLUSTER_NAME}
    
  8. Set the default zone or region:

    kpt cfg set asm gcloud.compute.location ${CLUSTER_LOCATION}
    
  9. Set the tag to the version of Anthos Service Mesh that you are installing:

    kpt cfg set asm anthos.servicemesh.tag 1.8.6-asm.8
    
  10. Set the revision in Anthos Service Mesh package resource configuration files:

    kpt cfg set asm anthos.servicemesh.rev asm-186-8
    
  11. Output the values of the kpt setters:

    kpt cfg list-setters asm
    

    The output of the command is similar to the following:

                              NAME                                                       VALUE
    anthos.servicemesh.canonicalServiceHub               gke.gcr.io/asm/canonical-service-controller:1.8.6-asm.8
    anthos.servicemesh.controlplane.monitoring.enabled   true
    anthos.servicemesh.hub                               gke.gcr.io/asm
    anthos.servicemesh.hubMembershipID                   MEMBERSHIP_ID
    anthos.servicemesh.tag                               1.8.6-asm.8
    anthos.servicemesh.trustDomainAliases
    base-dir                                             base
    gcloud.compute.location                              us-central
    gcloud.compute.network                               default
    gcloud.compute.subnetwork                            default
    gcloud.container.cluster                             example-cluster-1
    gcloud.container.cluster.clusterSecondaryRange
    gcloud.container.cluster.releaseChannel              REGULAR
    gcloud.container.cluster.servicesSecondaryRange
    gcloud.container.nodepool.max-nodes                  4
    gcloud.core.project                                  example-project-12345
    gcloud.project.environProjectID                      FLEET_PROJECT_ID
    gcloud.project.environProjectNumber                  1234567890123
    gcloud.project.projectNumber                         9876543210987

    Verify that the values for the following setters are correct:

    • anthos.servicemesh.rev
    • anthos.servicemesh.tag
    • gcloud.compute.location
    • gcloud.container.cluster
    • gcloud.core.project
    • gcloud.project.environProjectNumber

    You can ignore the values for the other setters.

Migrating to Anthos Service Mesh

Mesh CA

  1. Verify that the current kubeconfig context is pointing to the cluster that you want to install Anthos Service Mesh on:

    kubectl config current-context
    

    The output is in the following format:

    gke_PROJECT_ID_CLUSTER_LOCATION_CLUSTER_NAME

    The kubeconfig context and the values of the kpt setters must match. If needed, run the gcloud container clusters get-credentials command to set the current kubeconfig context.

  2. If needed, change to the istio-1.8.6-asm.8 directory. The istioctl client is version dependent. Make sure that you use the version in the istio-1.8.6-asm.8/bin directory.

  3. Run the following command to deploy the new control plane with the asm-gcp-multiproject profile. If you want to enable a supported optional feature, include -f and the YAML filename on the following command line. See Enabling optional features for more information.

    bin/istioctl install \
      -f asm/istio/istio-operator.yaml \
      -f asm/istio/options/multiproject.yaml \
      -f asm/istio/options/multicluster.yaml \
      -f asm/istio/options/revisioned-istio-ingressgateway.yaml \
      --revision=asm-186-8
    

    The --revision argument adds a revision label in the format istio.io/rev=asm-186-8 to istiod. The revision label is used by the automatic sidecar injector webhook to associate injected sidecars with a particular istiod revision. To enable sidecar auto-injection for a namespace, you must label it with a revision matching an istiod Deployment.

    The following files override the settings in the istio-operator.yaml file:

    • The multiproject.yaml file sets the asm-gcp-multiproject profile.

    • The multicluster.yaml file configures the settings that Anthos Service Mesh needs for a multi-cluster configuration.

    • The revisioned-istio-ingressgateway.yaml file configures a revisioned Deployment for the istio-ingressgateway.

  4. Check that the control plane pods in istio-system are up:

    kubectl get pods -n istio-system
    

    Example output:

    NAME                                        READY   STATUS    RESTARTS   AGE
    istio-ingressgateway-c56675fcd-86zdn        1/1     Running   0          2m9s
    istio-ingressgateway-c56675fcd-vn4nv        1/1     Running   0          2m21s
    istiod-asm-186-8-6d5cfd4b89-xztlr           1/1     Running   0          3m44s
    istiod-fb7f746f4-wcntn                      1/1     Running   0          50m

    You have two control plane Deployments and Services running side-by-side.

  5. Deploy the Canonical Service controller to your cluster:

    kubectl apply -f asm/canonical-service/controller.yaml

    The Canonical Service controller groups workloads belonging to the same logical service. For more information about Canonical Services, see the Canonical Service overview.

Citadel

  1. Verify that the current kubeconfig context is pointing to the cluster that you want to install Anthos Service Mesh on:

    kubectl config current-context
    

    The output is in the following format:

    gke_PROJECT_ID_CLUSTER_LOCATION_CLUSTER_NAME

    The kubeconfig context and the values of the kpt setters must match. If needed, run the gcloud container clusters get-credentials command to set the current kubeconfig context.

  2. If needed, change to the istio-1.8.6-asm.8 directory. The istioctl client is version dependent. Make sure that you use the version in the istio-1.8.6-asm.8/bin directory.

  3. Run the following command to deploy the new control plane with the asm-gcp-multiproject profile. If you want to enable a supported optional feature, include -f and the YAML filename on the following command line. See Enabling optional features for more information.

    bin/istioctl install \
      -f asm/istio/istio-operator.yaml \
      -f asm/istio/options/citadel-ca.yaml \
      -f asm/istio/options/multiproject.yaml \
      -f asm/istio/options/multicluster.yaml \
      -f asm/istio/options/revisioned-istio-ingressgateway.yaml \
      --revision=asm-186-8
    

    The --revision argument adds a revision label in the format istio.io/rev=asm-186-8 to istiod. The revision label is used by the automatic sidecar injector webhook to associate injected sidecars with a particular istiod revision. To enable sidecar auto-injection for a namespace, you must label it with a revision matching an istiod Deployment.

    The following files override the settings in the istio-operator.yaml file:

    • The citadel-ca.yaml configures Citadel as the CA.

    • The multiproject.yaml file sets the asm-gcp-multiproject profile.

    • The multicluster.yaml file configures the settings that Anthos Service Mesh needs for a multi-cluster configuration.

    • The revisioned-istio-ingressgateway.yaml file configures a revisioned Deployment for the istio-ingressgateway.

  1. Check that the control plane pods in istio-system are up:

      kubectl get pods -n istio-system
    

    Example output:

      NAME                                        READY   STATUS    RESTARTS   AGE
      istio-ingressgateway-c56675fcd-86zdn        1/1     Running   0          2m9s
      istio-ingressgateway-c56675fcd-vn4nv        1/1     Running   0          2m21s
      istiod-asm-186-8-6d5cfd4b89-xztlr           1/1     Running   0          3m44s
      istiod-fb7f746f4-wcntn                      1/1     Running   0          50m

    You have two control plane Deployments and Services running side-by-side.

    1. Deploy the Canonical Service controller to your cluster:

      kubectl apply -f asm/canonical-service/controller.yaml

      The Canonical Service controller groups workloads belonging to the same logical service. For more information about Canonical Services, see the Canonical Service overview.

Deploying and redeploying workloads

Your installation isn't complete until you enable automatic sidecar proxy injection (auto-injection). Migrations from OSS Istio and upgrades follow the revision-based upgrade process (referred to as "canary upgrades" in the Istio documentation). With a revision-based upgrade, the new version of the control plane is installed alongside the existing control plane. You then move some of your workloads to the new version, which lets you monitor the effect of the upgrade with a small percentage of the workloads, before migrating all of the traffic to the new version.

When you ran istioctl install, you set a revision label in the format istio.io/rev=asm-186-8 on istiod. To enable auto-injection, add a matching revision label to your namespace(s). The revision label is used by the sidecar injector webhook to associate injected sidecars with a particular istiod revision. After adding the label, restart the Pods in the namespace for sidecars to be injected.

If you included revisioned-istio-ingressgateway.yaml when you ran istioctl install, a revisioned Deployment is configured for the istio-ingressgateway. This allows you to control when you switch to the new version.

  1. Get the revision label that is on istiod and the istio-ingressgateway.

    kubectl get pod -n istio-system -L istio.io/rev
    

    The output from the command is similar to the following.

    NAME                                             READY   STATUS    RESTARTS   AGE   REV
    istio-ingressgateway-65d884685d-6hrdk            1/1     Running   0          67m
    istio-ingressgateway-65d884685d-94wgz            1/1     Running   0          67m
    istio-ingressgateway-asm-182-2-8b5fc8767-gk6hb   1/1     Running   0          5s    asm-186-8
    istio-ingressgateway-asm-182-2-8b5fc8767-hn4w2   1/1     Running   0          20s   asm-186-8
    istiod-asm-176-1-67998f4b55-lrzpz                1/1     Running   0          68m   asm-178-10
    istiod-asm-176-1-67998f4b55-r76kr                1/1     Running   0          68m   asm-178-10
    istiod-asm-182-2-5cd96f88f6-n7tj9                1/1     Running   0          27s   asm-186-8
    istiod-asm-182-2-5cd96f88f6-wm68b                1/1     Running   0          27s   asm-186-8
    1. Note whether you have both the old and new versions of the istio-ingressgateway.

      • If you included the revisioned-istio-ingressgateway option when you upgraded, a canary upgrade of the istio-ingressgateway was done. In this case, your output shows both the old and new versions of the istio-ingressgateway.

      • If you didn't include revisioned-istio-ingressgateway when you upgraded, an in-place upgrade of the istio-ingressgateway was done. In this case, your output shows only the new version.

    2. In the output, under the REV column, note the value of the revision label for the new version. In this example, the value is asm-186-8.

    3. Also note the value in the revision label for the old istiod version. You need this to delete the old version of istiod when you finish moving workloads to the new version. In the example output, the value of the revision label for the old version is asm-178-10.

  2. If you have both the old and new versions of the istio-ingressgateway, switch the istio-ingressgateway to the new revision. In the following command, change REVISION to the value that matches the revision label of the new version.

    kubectl patch service -n istio-system istio-ingressgateway --type='json' -p='[{"op": "replace", "path": "/spec/selector/service.istio.io~1canonical-revision", "value": "REVISION"}]'

    Expected output: service/istio-ingressgateway patched

  3. Add the revision label to a namespace and remove the istio-injection label (if it exists). In the following command, change REVISION to the value that matches the new revision of istiod.

    kubectl label namespace NAMESPACE istio.io/rev=REVISION istio-injection- --overwrite

    If you see "istio-injection not found" in the output, you can ignore it. That means that the namespace didn't previously have the istio-injection label. Because auto-injection fails if a namespace has both the istio-injection and the revision label, all kubectl label commands in the Anthos Service Mesh documentation include removing the istio-injection label.

  4. Restart the Pods to trigger re-injection.

    kubectl rollout restart deployment -n NAMESPACE
  5. Verify that your Pods are configured to point to the new version of istiod.

    kubectl get pods -n NAMESPACE -l istio.io/rev=REVISION
  6. Test your application to verify that the workloads are working correctly.

  7. If you have workloads in other namespaces, repeat the steps to label the namespace and restart Pods.

  8. If you are satisfied that your application is working as expected, continue with the steps to transition to the new version of istiod. If there's an issue with your application, follow the steps to rollback.

  9. Run the following command again to confirm whether you have both the old and new versions of the istio-ingressgateway or only the new version. This determines how you handle transitioning to the new version of the istio-ingressgateway or rolling back to the old version.

    kubectl get pod -n istio-system -L istio.io/rev
    

    Complete the transition

    If you are satisfied that your application is working as expected, remove the old control plane to complete the transition to the new version.

    1. Change to the directory where the files from the anthos-service-mesh GitHub repository are located.

    2. Configure the validating webhook to use the new control plane.

      kubectl apply -f asm/istio/istiod-service.yaml
      
    3. If you have both the old and new versions of the istio-ingressgateway, delete the old istio-ingressgateway Deployment. The command that you run depends on whether you are migrating from Istio or upgrading from a previous version of Anthos Service Mesh:

      Migrate

      If you migrated from Istio, the old istio-ingressgateway doesn't have a revision label.

      kubectl delete deploy/istio-ingressgateway -n istio-system
      

      Upgrade

      If you upgraded from a previous Anthos Service Mesh version, in the following command, replace OLD_REVISION with the revision label for the previous version of the istio-ingressgateway.

      kubectl delete deploy -l app=istio-ingressgateway,istio.io/rev=OLD_REVISION -n istio-system --ignore-not-found=true
      
    4. Delete the old version of istiod. The command that you use depends on whether you are migrating from Istio or upgrading from a previous version of Anthos Service Mesh.

      Migrate

      If you migrated from Istio, the old istiod doesn't have a revision label.

      kubectl delete Service,Deployment,HorizontalPodAutoscaler,PodDisruptionBudget istiod -n istio-system --ignore-not-found=true
      

      Upgrade

      If you upgraded from a previous Anthos Service Mesh version, in the following command, make sure that OLD_REVISION matches the revision label for the previous version of istiod.

      kubectl delete Service,Deployment,HorizontalPodAutoscaler,PodDisruptionBudget istiod-OLD_REVISION -n istio-system --ignore-not-found=true
      
    5. Remove the old version of the IstioOperator configuration.

      kubectl delete IstioOperator installed-state-OLD_REVISION -n istio-system
      

      The expected output is similar to the following:

      istiooperator.install.istio.io "installed-state-OLD_REVISION" deleted

    Rollback

    If you encountered an issue when testing your application with the new version of istiod, follow these steps to rollback to the previous version:

    1. Switch back to the old version of the istio-ingressgateway. The command that you use depends on whether you have both the old and new versions of the istio-ingressgateway or only the new version.

      • If you have both the old and new versions of the istio-ingressgateway run the kubectl patch service command and replace OLD_REVISION with the old revision.

        kubectl patch service -n istio-system istio-ingressgateway --type='json' -p='[{"op": "replace", "path": "/spec/selector/service.istio.io~1canonical-revision", "value": "OLD_REVISION"}]'
        
      • If you only have the new version of the istio-ingressgateway, run the kubectl rollout undo command.

        kubectl -n istio-system rollout undo deploy istio-ingressgateway
        
    2. Relabel your namespace to enable auto-injection with the previous version of istiod. The command that you use depends on whether you used a revision label or istio-injection=enabled with the previous version.

      • If you used a revision label for auto-injection:

        kubectl label namespace NAMESPACE istio.io/rev=OLD_REVISION --overwrite
        
      • If you used istio-injection=enabled:

        kubectl label namespace NAMESPACE istio.io/rev- istio-injection=enabled --overwrite
        

      Expected output:

      namespace/NAMESPACE labeled
    3. Confirm that the revision label on the namespace matches the revision label on the previous version of istiod:

      kubectl get ns NAMESPACE --show-labels
      
    4. Restart the Pods to trigger re-injection so the proxies have the previous version:

      kubectl rollout restart deployment -n NAMESPACE
      
    5. If you have both the old and new versions of the istio-ingressgateway, remove the new istio-ingressgateway Deployment. Make sure that the value of REVISION in the following command is correct.

      kubectl delete deploy -l app=istio-ingressgateway,istio.io/rev=REVISION -n istio-system --ignore-not-found=true
      
    6. Remove the new version of istiod. Make sure that the value of REVISION in the following command is correct.

      kubectl delete Service,Deployment,HorizontalPodAutoscaler,PodDisruptionBudget istiod-REVISION -n istio-system --ignore-not-found=true
      
    7. Remove the new version of the IstioOperator configuration.

      kubectl delete IstioOperator installed-state-REVISION -n istio-system
      

      Expected output is similar to the following:

      istiooperator.install.istio.io "installed-state-REVISION" deleted
    8. If you didn't include the --disable_canonical_service flag, the script enabled the Canonical Service controller. We recommend that you leave it enabled, but if you need to disable it, see Enabling and disabling the Canonical Service controller.

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