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Walid Shaari walidshaari

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walidshaari /
Created Feb 4, 2021 — forked from luckylittle/
Red Hat DO425 Notes

Red Hat Security: Securing Containers & OpenShift (DO425)

Last update: Tue Jan 14 23:15:49 UTC 2020 by @luckylittle


  1. Understand, identify, and work with containerization features
    1. Deploy a preconfigured application and identify crucial features such as namespaces, SELinux labels, and cgroups
View K8s networking
cbr0 the bridge that links the pods to each other within the node or in other nodes and hence to the external network
flannel0 VXLAN interface acts like any other vNIC device.packets gets routed from cbr0 to flannel0 device if ther is communition between pods in different nodes.
K8s services use iptables to connect a request to its final end point "ep". the svc will be implemented across every nodes in k8s cluster. that managment and update of iptables is guranteed by the kube-proxy, kube proxy is one of the k8s controller that watches the api-server for any service changes and keeps tracks of services and end points.
kube-dns is the in-house dns server, it automticaly adds new services to its records, serving A, and SRV records.
View Kubernetes vagrant cluster
install bash-completion package
kubeadm completion bash|tee /etc/bash_completion.d/kubeadm
kubectl completion bash|tee /etc/bash_completion.d/kubectl
Bootstrapping the master node "Kubernetes control panel" :
kubeadm init --apiserver-advertise-address= --pod-network-cidr= --kubernetes-version=v1.6.2
## for calico default is for flannel it is, not sure what needs to be done to vagrant for ips not clash
walidshaari / Dhahran-docker-meetup Nov 2016
Last active Nov 20, 2016
Saudi Eastern province Dhahran -Docker meetup
View Dhahran-docker-meetup Nov 2016
Make sure you have a Docker Hub account, if not please register with a good name as it will present your future software repositroy, think of it as you application store, such as Google play, or Apple store, mine for example is wshaari, some of the official names are docker, redhat, microsoft, mysql.
Create a Docker Hub account here at You will need a Docker Hub account to access the course materials.
Also register to Docker community so that you can get access to remote mentors, chat with other particpants, ask questions, among other chat activities
Bring your laptop fully charged.
Prefereably you laptop should have Docker already set-up. if you can not, do not worry as we will have access to online labs, and there are some computers already in the facility. but could prove helpful if there is network congestion, or internet issues if you are interetsed t