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Kubernetes/OpenShift Interview Questions - Containerization

1. How packet flows from one namespace to another namespace service 2. Taints Tolerations and Node selector, how according to memory taints and Tolerations or node selector can be put to node for pod schedule  3. What are Deployment strategies 4. What are Canary and Blue green deployment 5. Difference in HTTP and HTTPS protocol 6.  Difference in  TCP and UDP Protocol 7.  Difference in  Application firewall and network firewall 8.  Difference in  Soft link and hard link 9. What are System calls ?  10. What are Static pod and why needed in Kubernetes ? Examples of Static pod ------- Static Pods are managed directly by the kubelet daemon on a specific node, without the API server observing them.  Static Pods are always bound to one Kubelet on a specific node. 11. What is Heapster in Kubernetes ------ Heapster is a cluster-wide aggregator of monitoring and event data.  It currently supports Kubernetes natively and works on all Kube...

eBPF - Calico

eBPF is a Linux kernel feature that allows fast yet safe mini-programs to be loaded into the kernel in order to customize its operation. eBPF stands for “extended Berkeley Packet Filter”. The Berkeley Packet Filter was an earlier, more specialized virtual machine that was tailored for filtering packets. Tools such as  tcpdump  use this “classic” BPF VM to select packets that should be sent to userspace for analysis. eBPF is a considerably extended version of BPF that is suitable for general purpose use inside the kernel. While the name has stuck, eBPF can be used for a lot more than just packet filtering. eBPF is a virtual machine embedded within the Linux kernel. It allows small programs to be loaded into the kernel, and attached to hooks, which are triggered when some event occurs. This allows the behaviour of the kernel to be (sometimes heavily) customised. While the eBPF virtual machine is the same for each type of hook, the capabilities of the hooks vary considerably...

Calico Certified Operator: AWS Expert Questions & Answers

Section 1 Which one of the following is NOT an AWS networking concept? 1 point possible (graded, results hidden) AWS Region Virtual Private Cloud Elastic Network Interface Cloud NAT submitted Which of the following are network configuration options for the Calico CNI in BYOC clusters? 1 point possible (graded, results hidden) Select all that apply: VLAN based segmentation VXLAN encapsulation IP-IP encapsulation CrossSubnet mode submitted Why does AWS-CNI networking make use of source based routing on the nodes? 1 point possible (graded, results hidden) To provide more available IP addresses To allow the utilisation of all ENIs attached to the node To secure the node’s compute resources To ensure all pods use the same ENI submitted Which of the following are true when using the CrossSubnet mode in Calico CNI on BYOC clusters? 1 point possible (graded, results hidden) Select all that apply: It is recommended that for best performanc...