You can specify inventory file host path or comma separated host list. Except “localhost”, you can always specify a inventory using “-i INVENTORY” or –inventory=INVENTORY. Also, there are two default groups: all and ungrouped. “all” contains every host of the inventory file host path or comma separated host list and “ungrouped” contains all hosts that…
It is quite possible that you may need to get package updates through a proxy, or even get some package updates through a proxy and access other packages not through a proxy. Or maybe a script you might wish to call may also need certain environment variables set to run properly. Ansible makes it easy…
RHEL / Centos Ubuntu How to remove or cleanup kubernetes worker nodes in Centos 7? How to remove or cleanup kubernetes worker nodes in Ubuntu? Rajesh KumarI’m a DevOps/SRE/DevSecOps/Cloud Expert passionate about sharing knowledge and experiences. I have worked at Cotocus. I share tech blog at DevOps School, travel stories at Holiday Landmark, stock market…
What is Kubeadm? Kubeadm helps you bootstrap a minimum viable Kubernetes cluster that conforms to best practices. Kubeadm is a tool built to provide kubeadm init and kubeadm join as best-practice “fast paths” for creating Kubernetes clusters. Goal To Install a single master Kubernetes cluster To Install a high availability master Kubernetes cluster To Install…
Errors Solutions https://stackoverflow.com/questions/39872332/how-to-fix-weave-net-crashloopbackoff-for-the-second-node Rajesh KumarI’m a DevOps/SRE/DevSecOps/Cloud Expert passionate about sharing knowledge and experiences. I have worked at Cotocus. I share tech blog at DevOps School, travel stories at Holiday Landmark, stock market tips at Stocks Mantra, health and fitness guidance at My Medic Plus, product reviews at TrueReviewNow , and SEO strategies at Wizbrand….
Errors Solutions https://stackoverflow.com/questions/47107117/how-to-debug-when-kubernetes-nodes-are-in-not-ready-state https://stackoverflow.com/questions/50085323/kubernetes-worker-node-staying-in-notready-state Rajesh KumarI’m a DevOps/SRE/DevSecOps/Cloud Expert passionate about sharing knowledge and experiences. I have worked at Cotocus. I share tech blog at DevOps School, travel stories at Holiday Landmark, stock market tips at Stocks Mantra, health and fitness guidance at My Medic Plus, product reviews at TrueReviewNow , and SEO strategies at…
Error 1 Error 1 Error 2 Error 3 Solutions 3 Error 4 Solutions 4 Rajesh KumarI’m a DevOps/SRE/DevSecOps/Cloud Expert passionate about sharing knowledge and experiences. I have worked at Cotocus. I share tech blog at DevOps School, travel stories at Holiday Landmark, stock market tips at Stocks Mantra, health and fitness guidance at My Medic…
With the release of Kubernetes v1.14, Windows Server node support has officially graduated from beta to stable! This support enables developers and operators with Windows Server based applications to containerize them and benefit from the power of Kubernetes. Prior to this support, The v1.5 release of Kubernetes introduced alpha support for Windows Server based workers…
USING FORCE_DEREGISTER ADDED IN V1.1.2, IT WAS VERIFIED WHETHER AWS EC2 AMI CAN BE OVERWRITTEN. THE PROCESS IS TO DELETE THE AMI WITH THE SAME NAME AND THEN CREATE A NEW AMI. IN THIS VERIFICATION, BY USING FORCE_DELETE_SNAPSHOT TOGETHER, DO NOT LEAVE GARBAGE OF OLD AMI. Here is the sample programs for overwrite Existing AWS…
Install and Setup JDK 8 and JAVA HOME Install and Setup uDeploy Server 6.X How to start / Stop uDeploy server? Rajesh KumarI’m a DevOps/SRE/DevSecOps/Cloud Expert passionate about sharing knowledge and experiences. I have worked at Cotocus. I share tech blog at DevOps School, travel stories at Holiday Landmark, stock market tips at Stocks Mantra,…
When an Amazon EKS cluster is created, the IAM entity (user or role) that creates the cluster is added to the Kubernetes RBAC authorization table as the administrator (with system:master permissions. Initially, only that IAM user can make calls to the Kubernetes API server using kubectl. If you use the console to create the cluster,…
The hostPath volume mounts a resource from the host node filesystem. the resources could be directory, file socket, character, or block device. These resources mu A hostPath volume mounts a file or directory from the host node’s filesystem into your pod. A hostPath PersistentVolume must be used only in a single-node cluster. Kubernetes does not…
Here are the following facts for emptyDir storage type in Kubernetes An emptyDir volume is first created when a Pod is assigned to a Node and initially its empty A Volume of type emptyDir that lasts for the life of the Pod, even if the Container terminates and restarts. If a container in a Pod…
Kubernetes supports multiple virtual clusters backed by the same physical cluster. These virtual clusters are called namespaces. Namespaces ca be used in multiple environment with many users spread across multiple teams, or projects. Names of resources need to be unique within a namespace, but not across namespaces. Namespaces are a way to divide cluster resources…
A Probe is a diagnostic performed periodically by the kubelet on a Container. To perform a diagnostic, the kubelet calls a Handler implemented by the Container. There are three types of handlers: Each probe has one of three results: The kubelet can perform and react to two kinds of probes on running Containers: In this…
A Probe is a diagnostic performed periodically by the kubelet on a Container. To perform a diagnostic, the kubelet calls a Handler implemented by the Container. There are three types of handlers: Each probe has one of three results: The kubelet can perform and react to two kinds of probes on running Containers: In this…
You can restrict access based on the HTTP referrer. It’s not bulletproof (Referrer can be spoofed) but it will stop casual downloads. Suppose you have a website with domain name (www.devopsschool.com or devopsschool.com) with links to photos and videos stored in your S3 bucket, examplebucket. By default, all the S3 resources are private, so only…
This is one of the most frequest questions being asked in my workshop is that differences between using import or include in Ansible. For example import_role or include_role, what should be behaviour and what to expect? We know that include could be applied to tasks, plays and handlers. The bare include task (which was used…
It is possible to set variables at the command line using the –extra-vars (or -e) argument. Variables can be defined using a single quoted string (containing one or more variables) using one of the formats below. key=value Method 1 Method 2 An alternative to using command line args is to utilise environmental variables that are…
By design, Ansible executes just one play at a time. Your playbook consists of two plays (the two items in the root-level YAML list defined by the playbook file). Method 1 The following patterns address one or more groups. Groups separated by a colon indicate an “OR” configuration. This means the host may be in…
Both of them have some commonalities but they solve different purposes. vars_files are read when the play starts. include_vars are read when the play reaches the task. Format vars_files: directive and include_vars module vars_files: vars_file directive can only be used when defining a play to specify variable files. The variables from those files are included…