Leader-Election | COMP212-LCR and HS algorithms

After investigating a little more, I found that running logs on the container yielded standard_init_linux.go:228: exec user process caused: exec format error I opened an issue with the GitLab Operator project and they advised that GitLab Operator must be run on x64_86 architecture. The T4g series is AArch64/arm64. I switched to t2.xlarge and was able to bring up the operator.

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I have analyzed your issue and came to the following conclusions.

TL;DR: Unfortunately, the answer is: "not possible like you want it". The current workaround you are using with sed is the way to go. At the end of the day, even if a bit atypical, it is a practical solution.

First of all, the whole point of Kustomize is to apply different configurations from files or rather directories containing files to customize for multiple environments or the likes of environments. As such, if you know which values you would like to apply, than you would only have to include them in the corresponding overlay directory and apply whichever you would like to. For example, as part of the "development" and "production" overlays included here. That means hardcoding the namespace for each overlay.

But there is that question: "where do you get the namespace value from"? And, as a consequence, how dynamic it is - if not dynamic at all, simply one of a set of values, it is just a matter of using the approach I just described.

Let's assume it is fully dynamic:

There is a command for dynamic substitution of values: kustomize edit set but unfortunately it only takes these parameters: image, label, nameprefix, namespace, namesuffix, replicas so we cannot use it here (See the help for that command for more information). This is also an indication that dynamic substitution for arbitrary values has not been implemented yet.

I have also investigated other approaches and I can think of no "pure" Kustomize solution.

Looking directly from the code:

Is there a way to change both field without using sed, in 'pure' kustomize and without having to change manually value in kustomization.json?

I managed to achieve somewhat similar with the following configuration:

After a week I came up with the below configuration that worked,

Turns outthe tains on my nodegroup prevented the cert-manager pods from starting on any node

These commands helped debug and led me to a fix for this issue

Ok, the issue was not related to any configuration shown above. The debug logs of the nginx pods were full of error messages in regards to the kube-control namespaces. I was removing the Nginx helm chart completely and used the repositories suggested by Microsoft:

https://docs.microsoft.com/en-us/azure/aks/ingress-own-tls

Different levels of availability can be achieved in Kubernetes, it all depends on your requirements.

Your use case seem to be that only one replica should be active at the time to the database.

Even if you use a single replica in a Kubernetes Deployment or StatefulSet, it is regularly probed, using your declared LivenessProbe and ReadinessProbe.

If your app does not respond on LivenessProbe, a new pod will be created immediately.

Since only one replica at a time should have an active connection to your database, a leader election solution is viable.

The passive replicas, that currently does not have the lock, should regularly try to get the lock - so that they get active in case the old active pod has died. How this is done depend on the implementation and configuration.

If you want that only the active Pod in a multiplie replica solution should query the database, the app must first check if it has the lock (e.g. is the active instance).

There is not much difference between a single replica Deployment and a multi replica Deployment using leader election. There might be small differences in the time a failover takes.

For a single replica solution, you might consider using a StatefulSet instead of a Deployment due to different behavior when a node becomes unreachable.

You should not use 0.0.0.0 but the hostname as defined through the dockerfile. So at the zoo1 config server1 should be zoo1, at the zoo2 server2 should be zoo2 and at the zoo3 server should be zoo3.