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Admission Control and Policy Enforcement Rules applied before objects are created.WHAT ADMISSION CONTROL ISChecking or modifying objects... Alternatives to Full Orchestration Middle ground.WHAT EXISTS BETWEEN ONE SERVER AND A CLUSTERCompose on a single host, with a proxy... Backup Strategies for Containerised Systems What to protect.WHAT NEEDS BACKING UPData in volumes Databases, through their own tools... Building Images in a Pipeline Automating the build.WHAT THE PIPELINE SHOULD DOBuild the image Run tests Scan it Tag it Push it... Building Small Images Why size matters and how to reduce it.WHY SIZE MATTERSTransfer time on every deployment Storage... Building a Container Deployment Runbook Documenting how releases happen.WHY IT MATTERSDeployment knowledge concentrates in one person,... Capacity Planning for Container Platforms Sizing the infrastructure.WHAT TO MEASURE FIRSTActual resource use per workload, under realistic... Choosing Between a Cluster and Managed Containers The practical decision.WHAT A MANAGED CONTAINER SERVICE ISYou supply an image; the provider runs... Choosing a Base Image What to build on.WHAT THE OPTIONS AREA full distribution image A slim variant of one A minimal... Common Container Mistakes What goes wrong repeatedly.USING THE LATEST TAGNobody knows what is running, and it cannot be... Container Health Checks Telling the system whether a container is working.WHAT A HEALTH CHECK ISA command run... Container Image Security What you are running.WHAT THE RISKS AREVulnerabilities in the base image Vulnerabilities in your... Container Isolation and Its Limits How separate containers really are.WHAT ISOLATES THEMNamespaces, controlling what a process can... Container Logs Seeing what is happening.WHERE LOGS SHOULD GOStandard output and standard error.WHY NOT... Container Networking Basics How containers reach each other.WHAT THE DEFAULT NETWORK PROVIDESContainers able to reach the... Container Platform Costs What it adds up to.WHAT DRIVES COSTCompute for nodes Storage, including volumes and snapshots... Container Registries Where images live.WHAT A REGISTRY ISA service storing and serving images.WHAT THE OPTIONS... Container Registries You Run Yourself Hosting your own images.WHY RUN ONEControl over where images live No transfer charges to a third... Containers Against Virtual Machines Choosing between them.WHAT A VIRTUAL MACHINE PROVIDESA complete operating system, with its own... Containers and Continuous Delivery Shipping frequently and safely.WHAT CONTAINERS CONTRIBUTEOne artefact, identical from testing to... Containers and Orchestration: Everything That Matters, Briefly The whole category in one page.A CONTAINER IS A PROCESS, NOT A MACHINEThe kernel is shared, which... Containers in the Nigerian Context Local realities.WHAT CONSTRAINS THIS WORK HEREBandwidth cost and speed for image transfer Latency... Debugging a Container Working out why it is not behaving.WHAT TO CHECK FIRSTWhether it is running, or restarting... Deciding Your Container Strategy Choosing an approach deliberately.WHAT TO ESTABLISHHow many applications How often they change... Declarative Deployment From Version Control Managing clusters through files.WHAT THE APPROACH ISThe repository describes the desired state,... Deploying Containers to a Single Server The simplest production setup.WHAT IT LOOKS LIKEOne server, running containers, with a reverse... Deployment Strategies With Containers Ways to release.WHAT A ROLLING UPDATE ISReplacing instances gradually.WHAT IT PROVIDESNo... Designing Applications for Containers What the application must do differently.WHAT TO EXPECTBeing stopped at any moment Running as... Disaster Recovery for Container Platforms Rebuilding after a serious failure.WHAT TO DEFINEHow much data you can lose How long you can be... Environment Variables and Configuration Supplying settings to containers.WHY CONFIGURATION IS EXTERNALThe same image should run in every... Evaluating Whether Containers Helped Honest assessment.WHAT TO MEASURE BEFORE ADOPTINGDeployment frequency Time from commit to... Handling Application Configuration at Startup Failing fast and clearly.WHAT TO DO FIRSTValidate every required setting.WHYFailing immediately... Handling Application Secrets Rotation Changing credentials without downtime.WHAT THE PROBLEM ISChanging a credential invalidates the... Handling Cluster Add-Ons Components everyone installs.WHAT TYPICALLY GETS ADDEDAn ingress controller A certificate manager... Handling Container Registries Authentication Getting hosts able to pull.WHAT IS NEEDEDCredentials configured where images are pulled.WHERE... Handling Data and Volumes Persistence in a disposable world.WHAT HAPPENS TO DATA IN A CONTAINERIt disappears when the... Handling Long-Running and Batch Workloads Work that is not a web service.WHAT THIS COVERSData processing Report generation Media handling... Handling Pod Scheduling and Placement Deciding where workloads run.WHAT THE SCHEDULER USESResource requests Node capacity Constraints... Handling Secrets in Containers Credentials without leaking them.WHAT NOT TO DOBake secrets into images Pass them as build... Handling Stateful Applications Things that cannot simply be replaced.WHAT MAKES AN APPLICATION STATEFULData it holds that must... Handling Time, Locale and Time Zones in Containers Small details that cause real problems.WHAT MINIMAL IMAGES FREQUENTLY LACKTime zone data Locale... Handling Traffic Ingress and Certificates Getting requests into the cluster.WHAT AN INGRESS CONTROLLER DOESReceives external traffic and... Images, Layers and Containers The three things people confuse.WHAT AN IMAGE ISA packaged filesystem and configuration,... Installing and Getting Started With Docker First steps.WHAT TO INSTALLThe engine on a Linux server, or the desktop application... Jobs and Scheduled Work in Containers Work that runs and finishes.WHAT A JOB ISWork that runs to completion, rather than serving... Kubernetes Access Control Who may do what.WHAT THE MODEL ISRoles grant permissions; bindings attach roles to... Kubernetes Concepts The vocabulary.WHAT A CLUSTER ISA set of machines managed together.WHAT THE CONTROL PLANE... Kubernetes Configuration and Secrets Supplying settings.WHAT A CONFIGMAP ISKey-value configuration, non-secret.HOW IT REACHES A... Kubernetes Probes Liveness, readiness and startup.WHAT A LIVENESS PROBE DETERMINESWhether the container should be... Kubernetes Resource Requests and Limits Telling the scheduler what you need.WHAT A REQUEST ISThe amount guaranteed to the container.WHAT... Kubernetes Services and Networking Reaching pods.WHAT A SERVICE PROVIDESA stable name and address for a changing set of pods.HOW... Kubernetes Storage Persistence in a cluster.WHAT THE PROBLEM ISPods move between nodes, and local disk does not... Learning Containers and Orchestration Building the skill.WHAT TO LEARN FIRSTWhat a container actually is: a process, isolated.WHY THAT... Local Development With Containers Working on containerised applications.WHAT IT PROVIDESThe same dependencies as production New... Managed Kubernetes Services Letting a provider run the control plane.WHAT THEY PROVIDEThe control plane operated for you... Managing Cluster Nodes The machines underneath.WHAT A NODE RUNSThe workloads, plus agents managing them.WHAT TO... Managing Container Configuration Across Environments One image, many settings.WHAT THE PRINCIPLE ISThe same image runs everywhere, configured... Managing Container Host Disk Space The commonest operational failure.WHAT CONSUMES SPACEImages, including unused ones Stopped... Managing Multiple Environments in One Cluster Sharing infrastructure safely.WHAT PEOPLE DORun development, testing and production in one... Migrating an Existing Application to Containers Moving what already runs.WHAT TO ASSESS FIRSTWhether it can run as several instances What it... Monitoring Containers Observing many short-lived things.WHAT DIFFERS FROM MONITORING SERVERSInstances appear and... Multi-Architecture Images Running on different processors.WHY THIS ARISESServers are commonly one architecture, and many... Network Policies Restricting what can talk to what.WHAT THE DEFAULT ISEvery pod can reach every other pod, across... Observability in Container Platforms Understanding a distributed system.WHAT THE THREE KINDS AREMetrics: numbers over timeLogs:... Planning a Move to Containers Doing it deliberately.WHAT TO ESTABLISH FIRSTWhat problem you are solving.WHAT GOOD ANSWERS LOOK... Preparing for a Container Platform Incident Being ready when it breaks.WHAT TO PREPARE IN ADVANCEAccess that works when the cluster does not... Resource Quotas and Limit Ranges Bounding what a namespace can use.WHAT A QUOTA DOESCaps total resources in a namespace.WHAT IT... Reviewing a Containerised Deployment What to check before it goes live.WHAT TO CHECK ABOUT THE IMAGEPinned base, not a moving tag... Rolling Updates and Rollbacks Changing what is running.WHAT A ROLLING UPDATE DOESReplaces pods gradually, keeping the service... Running Containers Practical operation.WHAT TO SPECIFY WHEN RUNNINGThe image A name, so it can be referred to Port... Running Containers as Non-Root Reducing what a compromise can do.WHY IT MATTERSRoot inside a container is closer to root on the... Running Containers on Shared Hosting Infrastructure Constraints of managed environments.WHAT SHARED HOSTING OFFERSUsually no container support at... Running Databases in Containers When it is appropriate.WHAT WORKS WELLDevelopment and testing Ephemeral environments Small... Running Migrations in Containerised Deployments Changing the database during a rollout.WHAT THE PROBLEM ISSeveral instances deploy gradually, so... Scaling Containers Adding and removing capacity.WHAT MANUAL SCALING ISChanging the number of replicas.WHAT AUTOMATIC... Scanning Images for Vulnerabilities Finding known problems.WHAT A SCANNER DOESCompares the packages in an image against databases of... Service Meshes Managing communication between services.WHAT ONE ISInfrastructure handling service-to-service... Supply Chain Security for Images Trusting what you build on.WHAT THE SUPPLY CHAIN ISEverything entering your image: base images,... Testing With Containers Disposable environments for tests.WHAT THEY PROVIDEA real database, message broker or cache for... Troubleshooting Image Pull Failures When the image cannot be fetched.WHAT THE COMMON CAUSES AREA wrong image name or tag Missing... Troubleshooting Kubernetes Workloads Working out why something is not running.WHAT TO CHECK FIRSTThe pod's status.WHAT COMMON STATUSES... Understanding Build Cache Why builds are fast or slow.WHAT THE CACHE DOESReuses the result of an instruction when nothing... Understanding Container Image Provenance Knowing where an image came from.WHY IT MATTERSDeploying an image means running whatever it... Understanding Container Lifecycle From start to removal.WHAT THE STATES ARECreated Running Paused Stopped RemovedWHAT HAPPENS ON... Understanding Container Networking Models How traffic actually flows.WHAT THE REQUIREMENT IS IN A CLUSTEREvery pod can reach every other... Understanding Container Resource Consumption Where memory and processor go.WHAT A CONTAINER CONSUMESExactly what its process consumes, plus a... Understanding Container Security Contexts Settings that constrain a container.WHAT A SECURITY CONTEXT SETSThe user and group to run as... Understanding Ephemeral Storage Disk that is not a volume.WHAT IT ISSpace a container uses on the node's disk: the writable... Understanding Image Layers and Storage Drivers How images are stored on disk.WHAT A STORAGE DRIVER DOESCombines the read-only layers and the... Understanding Orchestrator Controllers How desired state is maintained.WHAT A CONTROLLER ISA loop comparing desired state against... Understanding Pod Disruption Why workloads move.WHAT INVOLUNTARY DISRUPTION ISA node failing, running out of resources, or... Understanding Sidecars and Init Containers Helpers alongside the main container.WHAT AN INIT CONTAINER ISOne that runs to completion before... Upgrading Clusters and Container Platforms Keeping the platform current.WHY IT MATTERSVersions fall out of support quickly, and unsupported... Using Docker Compose Running several containers together.WHAT IT PROVIDESA file describing several services, run with... What a Container Actually Is The idea, without the marketing.WHAT IT ISA process running on the host, isolated so it sees only... When Not to Use Kubernetes Recognising overkill.WHAT IT SOLVESScheduling across many hosts Recovery from host failure... Why Orchestration Exists The problem beyond one host.WHAT BREAKS WITH SEVERAL HOSTSDeciding which host runs what... Writing Kubernetes Manifests Describing what you want.WHAT A MANIFEST ISA file describing an object.WHAT EVERY ONE CONTAINSThe... Writing a Dockerfile Defining how an image is built.WHAT IT ISA text file of instructions, executed in order.WHAT THE... Zero-Downtime Deployment Checklist Getting a release right.WHAT THE APPLICATION MUST DOHandle a termination signal gracefully Finish...
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