Oracle Linux Cloud Native Environment (OLCNE)

Instructions for setting up an OLCNE cluster for Verrazzano

Prepare for the OCLNE install

Oracle Linux Cloud Native Environment can be installed in several different types of environments. These range from physical, on-premises hardware to virtualized cloud infrastructure. The Oracle Linux Cloud Native Environment installation instructions assume that networking and compute resources already exist. The basic infrastructure requirements are a network with a public and private subnet and a set of hosts connected to those networks.

OCI example

The following is an example of OCI infrastructure that can be used to evaluate Verrazzano installed on Oracle Linux Cloud Native Environment. If other environments are used, the capacity and configuration should be similar.

You can use the VCN Wizard of the OCI Console to automatically create most of the described network infrastructure. Additional security lists/rules, as detailed below, need to be added manually. All CIDR values provided are examples and can be customized as required.

Virtual Cloud Network (for example, CIDR 10.0.0.0/16)

Public Subnet (for example, CIDR 10.0.0.0/24)

Security List / Ingress Rules

Stateless Destination Protocol Source Ports Destination Ports Type & Code Description
No 0.0.0.0/0 ICMP 3, 4 ICMP errors
No 10.0.0.0/16 ICMP 3 ICMP errors
No 0.0.0.0/0 TCP All 22 SSH
No 0.0.0.0/0 TCP All 80 HTTP load balancer
No 0.0.0.0/0 TCP All 443 HTTPS load balancer

Security List / Egress Rules

Stateless Destination Protocol Source Ports Destination Ports Type & Code Description
No 10.0.1.0/24 TCP All 22 SSH
No 10.0.1.0/24 TCP All 30080 HTTP load balancer
No 10.0.1.0/24 TCP All 30443 HTTPS load balancer
No 10.0.1.0/24 TCP All 31380 HTTP load balancer
No 10.0.1.0/24 TCP All 31390 HTTPS load balancer

Private Subnet (for example, CIDR 10.0.1.0/24)

Security List / Ingress Rules

Stateless Destination Protocol Source Ports Destination Ports Type & Code Description
No 0.0.0.0/0 ICMP 3, 4 ICMP errors
No 10.0.0.0/16 ICMP 3 ICMP errors
No 10.0.0.0/16 TCP All 22 SSH
No 10.0.0.0/24 TCP All 30080 HTTP load balancer
No 10.0.0.0/24 TCP All 30443 HTTPS load balancer
No 10.0.0.0/24 TCP All 31380 HTTP load balancer
No 10.0.0.0/24 TCP All 31390 HTTPS load balancer
No 10.0.1.0/24UDP All 111 NFS
No 10.0.1.0/24 TCP All 111 NFS
No 10.0.1.0/24 UDP All 2048 NFS
No 10.0.1.0/24 TCP All 2048-2050 NFS
No 10.0.1.0/24 TCP All 2379-2380 Kubernetes etcd
No 10.0.1.0/24 TCP All 6443 Kubernetes API Server
No 10.0.1.0/24 TCP All 6446 MySQL
No 10.0.1.0/24 TCP All 8090-8091 OLCNE Platform Agent
No 10.0.1.0/24 UDP All 8472 Flannel
No 10.0.1.0/24 TCP All 10250-10255 Kubernetes Kublet

Security List / Egress Rules

Stateless Destination Protocol Source Ports Destination Ports Type and Code Description
No 10.0.0.0/0 TCP All egress traffic

DHCP Options

DNS Type
Internet and VCN Resolver

Route Tables

Public Subnet Route Table Rules

Destination Target
0.0.0.0/0 Internet Gateway

Private Subnet Route Table Rules

Destination Target
0.0.0.0/0 NAT Gateway
All OCI Services Service Gateway

Internet Gateway

NAT Gateway

Service Gateway

The following compute resources adhere to the guidelines provided in the Oracle Linux Cloud Native Environment Getting Started guide. The attributes indicated (for example, Subnet, RAM, Shape, and Image) are recommendations that have been tested. Other values can be used if required.

Compute Instances

Role Subnet Suggested RAM Compatible VM Shape Compatible VM Image
SSH Jump Host Public 8GB VM.Standard.E2.1 Oracle Linux 7.8
OLCNE Operator Host Private 16GB VM.Standard.E2.2 Oracle Linux 7.8
Kubernetes Control Plane Node Private 32GB VM.Standard.E2.4 Oracle Linux 7.8
Kubernetes Worker Node 1 Private 32GB VM.Standard.E2.4 Oracle Linux 7.8
Kubernetes Worker Node 2 Private 32GB VM.Standard.E2.4 Oracle Linux 7.8
Kubernetes Worker Node 3 Private 32GB VM.Standard.E2.4 Oracle Linux 7.8

Do the OLCNE install

Deploy Oracle Linux Cloud Native Environment with the Kubernetes module, following instructions from the Getting Started guide.

  • Use a single Kubernetes control plane node.
  • Skip the Kubernetes API load balancer (3.4.3).
  • Use private CA certificates (3.5.3).

Prepare for the Verrazzano install

A Verrazzano Oracle Linux Cloud Native Environment deployment requires:

  • A default storage provider that supports “Multiple Read/Write” mounts. For example, an NFS service like:
    • Oracle Cloud Infrastructure File Storage Service.
    • A hardware-based storage system that provides NFS capabilities.
  • Load balancers in front of the worker nodes in the cluster.
  • DNS records that reference the load balancers.

Examples for meeting these requirements follow.

Prerequisites Details


Storage

Verrazzano requires persistent storage for several components. This persistent storage is provided by a default storage class. A number of persistent storage providers exist for Kubernetes. This guide will focus on pre-allocated persistent volumes. In particular, the provided samples will illustrate the use of OCI’s NFS File System.

OCI example

Before storage can be exposed to Kubernetes, it must be created. In OCI, this is done using File System resources. Using the OCI Console, create a new File System. Within the new File System, create an Export. Remember the value used for Export Path as it will be used later. Also note the Mount Target’s IP Address for use later.

After the exports have been created, referenced persistent volume folders (for example, /example/pv0001) will need to be created. In OCI, this can be done by mounting the export on one of the Kubernetes worker nodes and creating the folders. In the following example, the value /example is the Export Path and 10.0.1.8 is the Mount Target’s IP Address. The following command should be run on one of the Kubernetes worker nodes. This will result in the creation of nine persistent volume folders. The reason for nine persistent volume folders is covered in the next section.

$ sudo mount 10.0.1.8:/example /mnt
$ for x in {0001..0009}; do sudo mkdir -p /mnt/pv${x} && sudo chmod 777 /mnt/pv${x}; done
Persistent Volumes

A default Kubernetes storage class is required by Verrazzano. When using pre-allocated PersistentVolumes, for example NFS, persistent volumes should be declared as following. The value for name may be customized but will need to match the PersistentVolume storageClassName value later.

  • Create a default StorageClass
    $ cat << EOF | kubectl apply -f -
      apiVersion: storage.k8s.io/v1
      kind: StorageClass
      metadata:
        name: example-nfs
        annotations:
          storageclass.kubernetes.io/is-default-class: "true"
      provisioner: kubernetes.io/no-provisioner
      volumeBindingMode: WaitForFirstConsumer
    EOF
    
  • Create the required number of PersistentVolume resources. The Verrazzano system requires five persistent volumes for itself. The following command creates nine persistent volumes. The value for storageClassName must match the above StorageClass name. The values for name may be customized. The value for path must match the Export Path of the Export from above, combined with the persistent volume folder from above. The value for server must be changed to match the location of your file system server.
    $ for n in {0001..0009}; do cat << EOF | kubectl apply -f -
      apiVersion: v1
      kind: PersistentVolume
      metadata:
        name: pv${n}
      spec:
        storageClassName: example-nfs
        accessModes:
          - ReadWriteOnce
          - ReadWriteMany
        capacity:
          storage: 50Gi
        nfs:
          path: /example/pv${n}
          server: 10.0.1.8
        volumeMode: Filesystem
        persistentVolumeReclaimPolicy: Recycle
    EOF
    

Load Balancers

Verrazzano on Oracle Linux Cloud Native Environment uses external load balancer services. These will not automatically be provided by Verrazzano or Kubernetes. Two load balancers must be deployed outside of the subnet used for the Kubernetes cluster. One load balancer is for management traffic and the other for application traffic.

Specific steps will differ for each load balancer provider, but a generic configuration and an OCI example follow.

Generic configuration:
  • Target Host: Host names of Kubernetes worker nodes
  • Target Ports: See table
  • External Ports: See table
  • Distribution: Round-robin
  • Health Check: TCP
Traffic Type Service Name Type Suggested External Port Target Port
Application istio-ingressgateway TCP 80 31380
Application istio-ingressgateway TCP 443 31390
Management ingress-controller-nginx-ingress-controller TCP 80 30080
Management ingress-controller-nginx-ingress-controller TCP 443 30443
OCI example

The following details can be used to create OCI load balancers for accessing application and management user interfaces, respectively. These load balancers will route HTTP/HTTPS traffic from the Internet to the private subnet. If load balancers are desired, then they should be created now even though the application and management endpoints will be installed later.

  • Application Load Balancer: Public Subnet
    • Listeners
      • HTTP Listener: Protocol TCP, Port 80
      • HTTPS Listener: Protocol TCP, Port 443
    • Backend Sets
      • HTTP Backend Sets:
        • Health Check: Protocol TCP, Port 31380
        • Backends: Kubernetes Worker Nodes, Port 31380, Distribution Policy Weighted Round Robin
      • HTTPS Backend Sets
        • Health Check: Protocol TCP, Port 31390
        • Backends: Kubernetes Worker Nodes, Port 31390, Distribution Policy Weighted Round Robin
  • Management Load Balancer: Public Subnet
    • Listeners
      • HTTP Listener: Protocol TCP, Port 80
      • HTTPS Listener: Protocol TCP, Port 443
    • Backend Sets
      • HTTP Backend Sets:
        • Health Check: Protocol TCP, Port 30080
        • Backends: Kubernetes Worker Nodes, Port 30080, Distribution Policy Weighted Round Robin
      • HTTPS Backend Sets
        • Health Check: Protocol TCP, Port 30443
        • Backends: Kubernetes Worker Nodes, Port 30443, Distribution Policy Weighted Round Robin

DNS

When using the spec.dns.external DNS type, the installer searches the DNS zone you provide for two specific A records. These are used to configure the cluster and should refer to external addresses of the load balancers in the previous step. The A records will need to be created manually.

NOTE: At this time, the only supported deployment for Oracle Linux Cloud Native Environment is the external DNS type.

Record Use
ingress-mgmt Set as the .spec.externalIPs value of the ingress-controller-nginx-ingress-controller service.
ingress-verrazzano Set as the .spec.externalIPs value of the istio-ingressgateway service.

For example:

198.51.100.10                                   A       ingress-mgmt.myenv.mydomain.com.
203.0.113.10                                    A       ingress-verrazzano.myenv.mydomain.com.

Verrazzano installation will result in a number of management services that need to point to the ingress-mgmt address.

keycloak.myenv.mydomain.com                      CNAME   ingress-mgmt.myenv.mydomain.com.
rancher.myenv.mydomain.com                       CNAME   ingress-mgmt.myenv.mydomain.com.

grafana.vmi.system.myenv.mydomain.com            CNAME   ingress-mgmt.myenv.mydomain.com.
prometheus.vmi.system.myenv.mydomain.com         CNAME   ingress-mgmt.myenv.mydomain.com.
kibana.vmi.system.myenv.mydomain.com             CNAME   ingress-mgmt.myenv.mydomain.com.
elasticsearch.vmi.system.myenv.mydomain.com      CNAME   ingress-mgmt.myenv.mydomain.com.

For simplicity, an administrator may want to create wildcard DNS records for the management addresses:

*.system.myenv.mydomain.com                      CNAME   ingress-mgmt.myenv.mydomain.com.

OR

*.myenv.mydomain.com                             CNAME   ingress-mgmt.myenv.mydomain.com.
OCI example

DNS is configured in OCI by creating DNS zones in the OCI Console. When creating a DNS zone, use these values:

  • Method: Manual
  • Zone Name: <dns-suffix>
  • Zone Type: Primary

The value for <dns-suffix> excludes the environment (for example, use the mydomain.com portion of myenv.mydomain.com).

DNS A records must be manually added to the zone and published using values described above. DNS CNAME records, in the same way.

During the Verrazzano install, these steps should be performed on the Oracle Linux Cloud Native Environment operator node.

Edit the sample Verrazzano custom resource install-olcne.yaml file and provide these configuration settings for your OLCNE environment:

  • The value for spec.environmentName is a unique DNS subdomain for the cluster (for example, myenv in myenv.mydomain.com).
  • The value for spec.dns.external.suffix is the remainder of the DNS domain (for example, mydomain.com in myenv.mydomain.com).
  • Under spec.ingress.verrazzano.nginxInstallArgs, the value for controller.service.externalIPs is the IP address of ingress-mgmt.<myenv>.<mydomain.com> configured during DNS set up.
  • Under spec.ingress.application.istioInstallArgs, the value for gateways.istio-ingressgateway.externalIPs is the IP address of ingress-verrazzano.<myenv>.<mydomain.com> configured during DNS set up.

You will install Verrazzano using the external DNS type (the example custom resource for OLCNE is already configured to use spec.dns.external).

Set the following environment variable:

The value for <path to valid Kubernetes config> is typically ${HOME}/.kube/config.

$ export KUBECONFIG=$VERRAZZANO_KUBECONFIG

Next steps

To continue, see the Installation Guide.


Last modified March 8, 2021: fix up docs (#104) (85b1d53)