檢視 Rancher Requirements 的原始碼

== Large Clusters ==
* A cluster is a set of nodes (physical or virtual machines) running Kubernetes agents, managed by the control plane.
** No more than 100 pods per node
** No more than 5,000 nodes
** No more than 150,000 total pods
** No more than 300,000 total containers
* Consider resource quotas
** Computer instances
** CPUs
** Storage volumes
** In-use IP addresses
** Packet filtering rule sets
** Number of load balancers
** Network subnets
** Log streams
* need a control plane with sufficient compute and other resources.
* store Event objects in a separate dedicated etcd instance
need a control plane with sufficient compute and other resources.
== RKE ==
high-availability RKE cluster
* '''Three Linux nodes''', typically virtual machines, in an infrastructure provider such as Amazon’s EC2, Google Compute Engine, or vSphere.
: These nodes must be in the same region/data center. You may place these servers in separate availability zones.
: Rancher server data is stored on etcd database that runs on all three nodes.
:* etcd is a distributed reliable key-value store for the most critical data of a distributed system, with a focus: Simple, Secure, Fast & Reliable.
:: etcd database requires an odd number of nodes so that it can always elect a leader with a majority of the etcd cluster.
: general installation requirements for OS, container runtime, hardware, and networking.
: {| class="wikitable" style="text-align: center;"
! Deployment Size || Clusters || Nodes || vCPUs || RAM
|-
! Small
| Up to 150 || Up to 1500 || 2 || 8 GB
|-
! Medium
| Up to 300 || Up to 3000 || 4 || 16 GB
|-
! Large
| Up to 500 || Up to 5000 || 8 || 32 GB
|-
! X-Large
| Up to 1000 || Up to 10,000 || 16 || 64 GB
|-
! XX-Large
| Up to 2000 || Up to 20,000 || 32 || 128 GB
|}
: Contact Rancher for more than 2000 clusters and/or 20,000 nodes.
* '''A load balancer''' to direct front-end traffic to the three nodes.
: RKE tool will deploy an NGINX Ingress controller.
: This controller will listen on ports 80 and 443 of the worker nodes, answering traffic destined for specific hostnames.
:* A layer-4 load balancer
:: Install NGINX, '''stream''' module is required.
:: <code>/etc/nginx/nginx.conf</code>
 worker_processes 4;
 worker_rlimit_nofile 40000;
 
 events {
     worker_connections 8192;
 }
 
 stream {
     upstream rancher_servers_http {
         least_conn;
         server <IP_NODE_1>:80 max_fails=3 fail_timeout=5s;
         server <IP_NODE_2>:80 max_fails=3 fail_timeout=5s;
         server <IP_NODE_3>:80 max_fails=3 fail_timeout=5s;
     }
     server {
         listen 80;
         proxy_pass rancher_servers_http;
     }
 
     upstream rancher_servers_https {
         least_conn;
         server <IP_NODE_1>:443 max_fails=3 fail_timeout=5s;
         server <IP_NODE_2>:443 max_fails=3 fail_timeout=5s;
         server <IP_NODE_3>:443 max_fails=3 fail_timeout=5s;
     }
     server {
         listen     443;
         proxy_pass rancher_servers_https;
     }
 
 }

 docker run -d --restart=unless-stopped \
   -p 80:80 -p 443:443 \
   -v /etc/nginx.conf:/etc/nginx/nginx.conf \
   nginx:1.14
:* A layer-7 load balancer
* '''A DNS record''' to map a URL to the load balancer. This will become the Rancher server URL, and downstream Kubernetes clusters will need to reach it.
== RancherD ==
{| class="wikitable" style="text-align: center;"
! Deployment Size || Clusters || Nodes || vCPUs || RAM
|-
! Small
| Up to 5 || Up to 50 || 2 || 5 GB
|-
! Medium
| Up to 15 || Up to 200 || 3 || 9 GB
|}
== Worker ==
=== Linux ===
* Requirements
** 1 core CPU
** 1 GB memory
* Install the Required CLI Tools
: kubectl - Kubernetes command-line tool.
: helm - Package management for Kubernetes.
* Add the Helm Chart Repository
 helm repo add rancher-stable https://releases.rancher.com/server-charts/stable
* Create a Namespace for Rancher
 kubectl create namespace cattle-system
* Choose your SSL Configuration
{| class="wikitable"
! Configuraton || Helm Chart Option || Requires cert-manager
|-
| Rancher Generated Certificates (Default) || ingress.tls.source=rancher || align="center" | yes
|-
| Let’s Encrypt || ingress.tls.source=letsEncrypt || align="center" | yes
|-
| Certificates from Files || ingress.tls.source=secret || align="center" | no
|}
* Install cert-manager (if requires)
 # Install the CustomResourceDefinition resources separately
 kubectl apply --validate=false -f https://github.com/jetstack/cert-manager/releases/download/v1.0.4/cert-manager.crds.yaml
 
 # **Important:**
 # If you are running Kubernetes v1.15 or below, you
 # will need to add the `--validate=false` flag to your
 # kubectl apply command, or else you will receive a
 # validation error relating to the
 # x-kubernetes-preserve-unknown-fields field in
 # cert-manager’s CustomResourceDefinition resources.
 # This is a benign error and occurs due to the way kubectl
 # performs resource validation.
 
 # Create the namespace for cert-manager
 kubectl create namespace cert-manager
 
 # Add the Jetstack Helm repository
 helm repo add jetstack https://charts.jetstack.io
 
 # Update your local Helm chart repository cache
 helm repo update
 
 # Install the cert-manager Helm chart
 helm install \
   cert-manager jetstack/cert-manager \
   --namespace cert-manager \
   --version v1.0.4

 kubectl get pods --namespace cert-manager
 
 NAME                                       READY   STATUS    RESTARTS   AGE
 cert-manager-5c6866597-zw7kh               1/1     Running   0          2m
 cert-manager-cainjector-577f6d9fd7-tr77l   1/1     Running   0          2m
 cert-manager-webhook-787858fcdb-nlzsq      1/1     Running   0          2m
* Install Rancher with Helm and Your Chosen Certificate Option
: Rancher Generated Certificates (Default)
 helm install rancher rancher-latest/rancher \
   --namespace cattle-system \
   --set hostname=rancher.my.org

 kubectl -n cattle-system rollout status deploy/rancher
 Waiting for deployment "rancher" rollout to finish: 0 of 3 updated replicas are available...
 deployment "rancher" successfully rolled out
:* HTTP Proxy
:* Private Docker Image Registry
:* TLS Termination on an External Load Balancer
* Verify that the Rancher Server is Successfully Deployed
 kubectl -n cattle-system rollout status deploy/rancher
 Waiting for deployment "rancher" rollout to finish: 0 of 3 updated replicas are available...
 deployment "rancher" successfully rolled out

 kubectl -n cattle-system get deploy rancher
 NAME      DESIRED   CURRENT   UP-TO-DATE   AVAILABLE   AGE
 rancher   3         3         3            3           3m
* Save Your Options
: Make sure you save the <code>--set</code> options you used.
* Finishing Up
* Optional Next Steps
: Enable the Enterprise Cluster Manager.
=== Windows ===
* Docker Engine - Enterprise Edition (EE)
* Requirements
** 2 core CPUs
** 5 GB memory
** 50 GB disk space
* Rancher only supports Windows using Flannel as the network provider.
: 2 network options: Host Gateway (L2bridge) and VXLAN (Overlay)(default)
:* Host Gateway (L2bridge): 
:: best to use the same Layer 2 network for all nodes. Otherwise, you need to configure the route rules for them.
:: maybe need to disable private IP address checks
:* VXLAN (Overlay): 
:: KB4489899 hotfix must be installed
* Minimum Architecture Requirements
{| class="wikitable"
! Operating System || Kubernetes Cluster Role || Purpose
|-
| Linux || Control plane, etcd, worker || Manage the Kubernetes cluster
|-
| Linux || Worker || Support the Rancher Cluster agent, Metrics server, DNS, and Ingress for the cluster
|-
| Windows Server core 1809 or above || Worker || Run your Windows containers
|}
__NOTOC__
[[Category:Kubernetes]]
[[Category:Rancher]]