Oracle 1z0-1084-22 Dumps

After a new version of Kubernetes has been released and when Container Engine forKubernetes supports the new version, you can use Container Engine for Kubernetes to upgrade master nodes running older versions of Kubernetes. Because Container Engine for Kubernetes distributes the Kubernetes Control Plane on multiple Oracle-managed master nodes (distributed across different availability domains in a region where supported) to ensure high availability, you're able to upgrade the Kubernetes version running on master nodes with zero downtime.

Having upgraded master nodes to a new version ofKubernetes, you can subsequently create new node pools running the newer version. Alternatively, you can continue to create new node pools that will run older versions of Kubernetes (providing those older versions are compatible with the Kubernetes version running on the master nodes).

Note that you upgrade master nodes by performing an ‘in-place’ upgrade, but you upgrade worker nodes by performing an ‘out-of-place’ upgrade. To upgrade the version of Kubernetes running on worker nodes in a node pool, you replace the original node pool with a new node pool that has new worker nodes running the appropriate Kubernetes version. Having 'drained' existing worker nodes in the original node pool to prevent new pods starting and to delete existing pods, you can thendelete the original node pool.

Upgrading the Kubernetes Version on Worker Nodes in a Cluster:

After a new version of Kubernetes has been released and when Container Engine for Kubernetes supports the new version, you can use Container Engine for Kubernetes to upgrade master nodes running older versions of Kubernetes. Because Container Engine for Kubernetes distributes the Kubernetes Control Plane on multiple Oracle-managed master nodes (distributed across different availability domains in a region where supported) to ensure high availability, you're able to upgrade the Kubernetes version running on master nodes with zero downtime.

You can upgrade the version of Kubernetes running on the worker nodes in a cluster in two ways:

(A) Perform an 'in-place' upgrade of a node pool in the cluster, by specifying a more recent Kubernetes version for new worker nodes starting in the existing node pool. First, you modify the existing node pool's properties to specify the more recent Kubernetes version. Then, you 'drain'existing worker nodes in the node pool to prevent new pods starting, and to delete existing pods. Finally, you terminate each of the worker nodes in turn. When new worker nodes are started in the existing node pool, they run the more recent Kubernetes version you specified. See Performing an In-Place Worker Node Upgrade by Updating an Existing Node Pool.

(B) Perform an 'out-of-place'upgrade of a node pool in the cluster, by replacing the original node pool with a new node pool. First, you create a new node pool with a more recent Kubernetes version. Then, you 'drain' existing worker nodes in the original node pool to prevent new podsstarting, and to delete existing pods. Finally, you delete the original node pool. When new worker nodes are started in the new node pool, they run the more recent Kubernetes version you specified. See Performing an Out-of-Place Worker Node Upgrade by Replacing an Existing Node Pool with a New Node Pool.

Note that in both cases:

The more recent Kubernetes version you specify for the worker nodes in the node pool must be compatible with the Kubernetes version running on the master nodes in the cluster. See Upgrading Clusters to Newer Kubernetes Versions).

You must drain existing worker nodes in the original node pool. If you don't drain the worker nodes, workloads running on the cluster are subject to disruption.

References:

https://docs.cloud.oracle.com/en-us/iaas/Content/ContEng/Tasks/contengupgradingk8sworkernode.htm

A PersistentVolume (PV) is a piece of storage in the cluster that has been provisioned by an administrator. PVs are volume plugins like Volumes, but have a lifecycle independent of any individual Pod that uses the PV.

A PersistentVolumeClaim (PVC) is a request for storage by a user. It is similar to a Pod. Pods consume node resources and PVCs consume PV resources.

If you intend to create Kubernetes persistent volumes,sufficient block volume quota must be available in each availability domain to meet the persistent volume claim. Persistent volume claims must request a minimum of 50 gigabytes

You can define and apply a persistent volume claim to your cluster, which in turn creates a persistent volume that's bound to the claim. A claim is a block storage volume in the underlying IaaS provider that's durable and offers persistent storage, enabling your data to remain intact, regardless of whether the containers that the storage is connected to are terminated.

With Oracle Cloud Infrastructure as the underlying IaaS provider, you can provision persistent volume claims by attaching volumes from the Block Storage service.

https://oracle.github.io/weblogic-kubernetes-operator/faq/oci-fss-pv/

https://kubernetes.i o/docs/concepts/storage/persistent-volumes/

Troubleshooting Oracle Functions:

There are common issues related to Oracle Functions and how you can address them.

Invoking a function returns a FunctionInvokeSubnetNotAvailable message and a 502 error (due to a DHCP Options issue)

When you invoke a function that you've deployed to OracleFunctions, you might see the following error message:

{"code":"FunctionInvokeSubnetNotAvailable","message":"dhcp options ocid1.dhcpoptions........ does not exist or Oracle Functions is not authorized to use it"}

Fn: Error invoking function. status: 502 message: dhcp options ocid1.dhcpoptions........ does not exist or Oracle Functions is not authorized to use it

If you see this error:

Double-check that a policy has been created to give Oracle Functions access to network resources.

Create Policies to ControlAccess to Network and Function-Related Resources:

Service Access to Network Resources

When Oracle Functions users create a function or application, they have to specify a VCN and a subnet in which to create them. To enable the Oracle Functions service tocreate the function or application in the specified VCN and subnet, you must create an identity policy to grant the Oracle Functions service access to the compartment to which the network resources belong.

To create a policy to give the Oracle Functions service access to network resources:

Log in to the Console as a tenancy administrator.

Create a new policy in the root compartment:

Open the navigation menu. Under Governance and Administration, go to Identity and click Policies.

Follow the instructions in To create a policy, and give the policy a name (for example, functions-service-network-access).

Specify a policy statement to give the Oracle Functions service access to the network resources in the compartment:

Allow service FaaS to use virtual-network-family in compartment

For example:

Allow service FaaS to use virtual-network-family in compartment acme-network

Click Create.

Double-check that the set of DHCP Options in the VCN specified for the application still exists.

References:

https://docs.cloud.oracle.c om/en-us/iaas/Content/Functions/Tasks/functionstroubleshooting.htm

https://docs.cloud.oracle.com/en-us/iaas/Content/Functions/Tasks/functionscre atingpolicies.htm