Upgrading PingDirectory ¶
Because PingDirectory is essentially a database, in its container form, each node in a cluster has its own persisted volume. Additionally, because PingDirectory is an application that focuses on state, rolling out an upgrade isn't really the same as any other configuration update. However, the product software, and scripts in the image provide a process through which upgrades are drastically simplified.
This use case focuses on a PingDirectory upgrade in a default Kubernetes environment where you upgrade a PingDirectory StatefulSet 188.8.131.52 to 184.108.40.206 using an incremental canary roll-out.
To ensure a successful upgrade process:
- Avoid combining configuration changes and version upgrades in the same rollout. This adds unnecessary complexity to debugging errors during an upgrade.
- Successfully complete an upgrade in a proper Dev/QA environment before trying anything in production.
- Upgrades will happen on one server at a time. Ensure you have enough resources on the remaining machines to prevent client impact.
- Follow a canary deployment pattern to ensure the changes will be successful before doing a full rollout. There is no good way to roll back a completed upgrade, so take any necessary steps to avoid this.
Before you begin ¶
- Complete Get Started to set up your DevOps environment and run a test deployment of the products.
- Clone or download the
pingidentity-devops-getting-started/20-kubernetes/12-pingdirectory-upgraderepository to your local
- Understand how to use our DevOps server profiles.
- Have access to a Kubernetes cluster and a default StorageClass.
- Understand how StatefulSets in Kubernetes is helpful.
- If you're upgrading in your own environment and using mounted licenses, have the license for the existing version in the
/opt/outpersisted volume and a license for the new version needs to be in
The license locations aren't an needed if you're using our DevOps credentials in an evaluation context.
About this task ¶
- Start with a base stack.
- Set up a partition to make changes on just one node.
- Deploy changes to one node and fix any errors.
- Rollout changes to other nodes.
Upgrade process overview ¶
The key functionality for PingDirectory upgrades is the relationship between the image hooks and the
manage-profile command in the product.
The upgrade is processed as follows:
When a node starts for the first time, it' i's in
SETUPmode and runs
When a node restarts (for whatever reason), it runs
This command compares the new profile to the old profile, and if there is a change, it tries standing up the server with the new profile.
Errors are thrown if there's a configuration in the new profile that prevents it from being applied.
manage-profile replace-profiledetects a product version difference, it takes the same approach as any other restart. It attempts to migrate PingDirectory to the new version, and if it can't, the command fails.
Because there is processing that happens automatically in the container during the upgrade, you should roll the change out to a small partition first and test it thoroughly before rolling it out to all. This partition also gives us room to revert back without impacting traffic in case something is not as expected.
This process in standard Kubernetes is called a Canary Rollout and is derived from Kubernetes documentation on StatefulSet update strategies.
"Canary Rollout" in this scenario focuses only on an incremental rollout of containers, not actually separating traffic. That could be done with additional tools like Istio or standing up another service and pairing separate labels and selectors.
Setting up the base stack ¶
The YAML configuration files for this use case are in your cloned local copy of the
To use the
1-initial.yamlfile in your local
pingidentity-devops-getting-started/20-kubernetes/12-pingdirectory-upgradedirectory to start with a PingDirectory StatefulSet using persistent volumes, enter:
kubectl apply -f 1-initial.yaml
All kubectl commands for this use case need to be run from the
This stands up a two directory topology, each with its own Persistent Volume Claim using the default storage class.
Wait for both nodes to be healthy before continuing and then enter:
kubectl get pods
Setting up a partition ¶
To use the
2-partition.yaml file in your local
pingidentity-devops-getting-started/20-kubernetes/12-pingdirectory-upgrade directory to add a partition to
kubectl apply -f 2-partition.yaml
This partition configuration signifies that any changes to
spec.template will only be applied to nodes with a cardinal value higher than the partition definition.
Staging changes ¶
To use the
3-staging.yaml file in your local
pingidentity-devops-getting-started/20-kubernetes/12-pingdirectory-upgrade directory to stage the change, enter:
kubectl apply -f 3-staging.yaml
The only actual change is to the image tag. When this change is applied:
pingdirectory-1pod is terminated and a new one with the new image is started.
The new PingDirectory container is based on a specific version of PingDirectory, found in the
manage-profile replace-profilecommand is eventually triggered when the container detects PingDirectory is in a
RESTARTstate. This command identifies the difference in the database version running, based on the persisted volume attached to
/opt/out, and then attempts to upgrade. Information similar to the following will be displayed:
... pingdirectory-1 Validating source and existing servers ..... Done pingdirectory-1 Updating the server version from 220.127.116.11 to 18.104.22.168. Local database backends pingdirectory-1 will be exported before the update in case a revert is necessary pingdirectory-1 Exporting backend with backendID userRoot. This may take a while ..... Done pingdirectory-1 Running the update tool ..... Done ... pingdirectory-1 Cleaning up after replace ..... Done pingdirectory-1 manage-profile replace-profile returned 0
This process requires having licenses for both server versions available and in the right location.
manage-profile replace-profilecompletes without error, you'll see the container continue the migration and eventually start up PingDirectory.
manage-profile replace-profilefails, an error is displayed and the container exits. The errors are because of some conflict in the server profile. The partition you set up previously provides an isolated environment for working out errors.
Work through any errors until you can get
manage-profile replace-profileto complete successfully before continuing.
Rolling out the changes ¶
When you're confident your upgrade will occur smoothly:
To use the
4-rollout.yaml file in your local
pingidentity-devops-getting-started/20-kubernetes/12-pingdirectory-upgrade directory to deploy the rollout to the remaining nodes, enter:
kubectl apply -f 4-rollout.yaml
This removes the partition.