I recently received an email from Microsoft Azure regarding some security vulnerabilities in AKS and to upgrade to >= 1.13.10:

Looking in the Azure Portal, there was only an option to upgrade to v1.12.8

and this was confirmed by running:

az aks get-upgrades --resource-group JCL-DevOps --name DevOps-K8s-Test --output table

As it is late at night my brain wasn’t working as it should be but thought I’d put a quick blog out there to say that if you are on v1.11.5 and want to upgrade to >= v1.13.10 then you have to do this in a 2 stage process by upgrading to v1.12.8 first:

az aks upgrade --resource-group myResourceGroup --name myAKSCluster --kubernetes-version 1.12.8
 az aks upgrade --resource-group myResourceGroup --name myAKSCluster --kubernetes-version 1.13.10

After upgrading to v1.12.8 you will now have the option to upgrade to v1.13.10 and then above that:

Now that I am up to 1.14.6, there are no further updates available:

az aks get-upgrades --resource-group myResourceGroup --name myAKSCluster --output table

As to why exactly this is I haven’t managed to find out yet but I have to assume it is like a lot of applications, it has to be a staged process – think upgrading SQL Server 2000 to SQL Server 2019, you can’t do this in 1 upgrade step 🙂

However, I’m a little confused and disappointed that this day in age and with the upgrade being minor version upgrades that it can’t be done in one go – perhaps I’m asking too much……………?

Upgrade scripts / path I used were:

az aks upgrade --resource-group myResourceGroup --name myAKSCluster --kubernetes-version 1.12.8
az aks upgrade --resource-group myResourceGroup --name myAKSCluster --kubernetes-version 1.13.10
az aks upgrade --resource-group myResourceGroup --name myAKSCluster --kubernetes-version 1.14.6