SPDX-License-Identifier: Apache-2.0
Copyright (c) 2019-2021 Intel Corporation

OpenNESS Cluster Setup

Quickstart

The following set of actions must be completed to set up the Open Network Edge Services Software (OpenNESS) cluster.

  1. Fulfill the Preconditions.
  2. Become familiar with supported features and enable them if desired.
  3. Clone Converged Edge Experience Kits
  4. Install deployment helper script pre-requisites (first time only)

     $ sudo scripts/ansible-precheck.sh
    
  5. Run the deployment helper script for the Ansible* playbook:

     $ python3 deploy.py
    

Preconditions

To use the playbooks, several preconditions must be fulfilled. These preconditions are described in the Q&A section below. The preconditions are:

  • CentOS* 7.9.2009 must be installed on all the nodes (the controller and edge nodes) where the product is deployed. It is highly recommended to install the operating system using a minimal ISO image on nodes that will take part in deployment (obtained from inventory file). Also, do not make customizations after a fresh manual install because it might interfere with Ansible scripts and give unpredictable results during deployment.
  • Hosts for the Edge Controller (Kubernetes control plane) and Edge Nodes (Kubernetes nodes) must have proper and unique hostnames (i.e., not localhost). This hostname must be specified in /etc/hosts (refer to Setup static hostname).
  • SSH keys must be exchanged between hosts (refer to Exchanging SSH keys between hosts).
  • A proxy may need to be set (refer to Setting proxy).
  • If a private repository is used, a Github* token must be set up (refer to GitHub token).
  • Refer to the Configuring time section for how to enable Network Time Protocol (NTP) clients.
  • The Ansible inventory must be configured (refer to Configuring the Inventory file).

Running playbooks

The Network Edge deployment and cleanup is carried out via Ansible playbooks. The playbooks are run from the Ansible host. Before running the playbooks, an inventory file inventory.yml must be defined. The provided deployment helper scripts support deploying multiple clusters as defined in the Inventory file.

The following subsections describe the playbooks in more details.

Deployment scripts

For convenience, playbooks can be executed by running helper deployment scripts from the Ansible host. These scripts require that the Edge Controller and Edge Nodes be configured on different hosts (for deployment on a single node, refer to Single-node Network Edge cluster). This is done by configuring the Ansible playbook inventory, as described later in this document.

To get started with deploying an OpenNESS edge cluster using the Converged Edge Experience Kit:

  1. Install pre-requisite tools for the the deployment script

     $ sudo scripts/ansible-precheck.sh
    
  2. Edit the inventory.yml file by providing information about the cluster nodes and the intended deployment flavor

    Example:

     ---
     all:
       vars:
         cluster_name: 5g_near_edge
         flavor: cera_5g_near_edge
         single_node_deployment: false
         limit:
     controller_group:
       hosts:
         ctrl.openness.org:
           ansible_host: 10.102.227.154
           ansible_user: openness
     edgenode_group:
       hosts:
         node01.openness.org:
           ansible_host: 10.102.227.11
           ansible_user: openness
         node02.openness.org:
           ansible_host: 10.102.227.79
           ansible_user: openness
     edgenode_vca_group:
       hosts:
     ptp_master:
       hosts:
     ptp_slave_group:
       hosts:
    

    NOTE: To deploy multiple clusters in one command run, append the same set of YAML specs separated by ---

  3. Additional configurations should be applied to the default group_vars file: inventory/default/group_vars/all/10-default.yml. More details on the default values is explained in the Getting Started Guide.

  4. Get the deployment started by executing the deploy script

     $ python3 deploy.py
    

    NOTE: This script parses the values provided in the inventory.yml file.

    NOTE: If want to enforce deployment termination in case of any failure, use arguments -f or --any-errors-fatal, e.g.:

    $ python3 deploy.py --any-errors-fatal
    
  5. To cleanup an existing deployment, execute with -c or --clean, e.g:

     $ python3 deploy.py --clean
    

    NOTE: If it is intended to do the cleanup manually, i.e: one cluster at a time, update the inventory.yml with only the intended cluster configuration

For an initial installation, deploy.py with all/vars/limit: controller must be run before deploy.py with all/vars/limit: nodes. During the initial installation, the hosts may reboot. After reboot, the deployment script that was last run should be run again.

Network Edge playbooks

The network_edge.yml and network_edge_cleanup.yml files contain playbooks for Network Edge mode. Playbooks can be customized by enabling and configuring features in the inventory/default/group_vars/all/10-default.yml file.

Cleanup procedure

The cleanup procedure is used when a configuration error in the Edge Controller or Edge Nodes must be fixed. The script causes the appropriate installation to be reverted, so that the error can be fixed and deploy.py can be re-run. The cleanup procedure does not do a comprehensive cleanup (e.g., installation of DPDK or Golang will not be rolled back).

The cleanup procedure call a set of cleanup roles that revert the changes resulted from the cluster deployment. The changes are reverted by going step-by-step in the reverse order and undoing the steps.

For example, when installing Docker*, the RPM repository is added and Docker is installed. When cleaning up, Docker is uninstalled and the repository is removed.

To execute cleanup procedure

$ python3 deploy.py --clean

NOTE: There may be leftovers created by the installed software. For example, DPDK and Golang installations, found in /opt, are not rolled back.

Supported EPA features

Several enhanced platform capabilities and features are available in OpenNESS for Network Edge. For the full list of supported features, refer to Building Blocks / Enhanced Platform Awareness section. The documents referenced in this list provide a detailed description of the features, and step-by-step instructions for enabling them. Users should become familiar with available features before executing the deployment playbooks.

VM support for Network Edge

Support for VM deployment on OpenNESS for Network Edge is available and enabled by default. Certain configurations and prerequisites may need to be satisfied to use all VM capabilities. The user is advised to become familiar with the VM support documentation before executing the deployment playbooks. See VM support in OpenNESS for Network Edge for more information.

Application on-boarding

Refer to the network-edge-applications-onboarding document for instructions on how to deploy edge applications for OpenNESS Network Edge.

Single-node Network Edge cluster

Network Edge can be deployed on just a single machine working as a control plane & node.

To deploy Network Edge in a single-node cluster scenario, follow the steps below:

  1. Modify inventory.yml

    Rules for inventory:

    • IP address (ansible_host) for both controller and node must be the same
    • controller_group and edgenode_group groups must contain exactly one host
    • single_node_deployment flag set to true

    Example of a valid inventory:

     ---
     all:
       vars:
         cluster_name: 5g_central_office
         flavor: cera_5g_central_office
         single_node_deployment: true   
         limit:  
     controller_group:
       hosts:
         controller:
           ansible_host: 10.102.227.234
           ansible_user: openness
     edgenode_group:
       hosts:
         node01:
           ansible_host: 10.102.227.234
           ansible_user: openness
     edgenode_vca_group:
       hosts:
     ptp_master:
       hosts:
     ptp_slave_group:
       hosts:
    
  2. Features can be enabled in the inventory/default/group_vars/all/10-default.yml file by tweaking the configuration variables.

  3. Settings regarding the kernel, grub, HugePages*, and tuned can be customized in inventory/default/group_vars/edgenode_group/10-default.yml.

    NOTE: Default settings in the single-node cluster mode are those of the Edge Node (i.e., kernel and tuned customization enabled).

  4. Single-node cluster can be deployed by running command:
     $ python3 deploy.py
    

Kubernetes cluster networking plugins (Network Edge)

Kubernetes uses 3rd party networking plugins to provide cluster networking. These plugins are based on the CNI (Container Network Interface) specification.

Converged Edge Experience Kits provide several ready-to-use Ansible roles deploying CNIs. The following CNIs are currently supported:

  • kube-ovn
    • Only as primary CNI
    • CIDR: 10.16.0.0/16
  • calico
    • Only as primary CNI
    • IPAM: host-local
    • CIDR: 10.245.0.0/16
    • Network attachment definition: openness-calico
  • flannel
    • IPAM: host-local
    • CIDR: 10.244.0.0/16
    • Network attachment definition: openness-flannel
  • weavenet
    • CIDR: 10.32.0.0/12
  • SR-IOV (cannot be used as a standalone or primary CNI - sriov setup)
  • Userspace (cannot be used as a standalone or primary CNI - Userspace CNI setup

Multiple CNIs can be requested to be set up for the cluster. To provide such functionality the Multus CNI is used.

NOTE: For a guide on how to add new a CNI role to the Converged Edge Experience Kits, refer to the Converged Edge Experience Kits guide.

Selecting cluster networking plugins (CNI)

The default CNI for OpenNESS is calico. Non-default CNIs may be configured with OpenNESS by editing the file inventory/default/group_vars/all/10-default.yml. To add a non-default CNI, the following edits must be carried out:

  • The CNI name is added to the kubernetes_cnis variable. The CNIs are applied in the order in which they appear in the file. By default, calico is defined. That is,

    kubernetes_cnis:
    - calico
    
  • To add a CNI, such as SR-IOV, the kubernetes_cnis variable is edited as follows:

    kubernetes_cnis:
    - calico
    - sriov
    
  • The Multus CNI is added by the Ansible playbook when two or more CNIs are defined in the kubernetes_cnis variable
  • The CNI’s networks (CIDR for pods, and other CIDRs used by the CNI) are added to the proxy_noproxy variable by Ansible playbooks.

Adding additional interfaces to pods

To add an additional interface from secondary CNIs, annotation is required. Below is an example pod yaml file for a scenario with kube-ovn as a primary CNI along with calico and flannel as additional CNIs. Multus* will create an interface named calico using the network attachment definition openness-calico and interface flannel using the network attachment definition openness-flannel.

NOTE: Additional annotations such as openness-calico@calico are required only if the CNI is secondary. If the CNI is primary, the interface will be added automatically by Multus*.

apiVersion: v1
kind: Pod
metadata:
  name: cni-test-pod
  annotations:
    k8s.v1.cni.cncf.io/networks: openness-calico@calico, openness-flannel@flannel
spec:
  containers:
  - name: cni-test-pod
    image: docker.io/centos/tools:latest
    command:
    - /sbin/init

The following is an example output of the ip a command run in a pod and after CNIs have been applied. Some lines in the command output were omitted for readability.

The following interfaces are available: calico@if142, flannel@if143, and eth0@if141 (kubeovn).

# kubectl exec -ti cni-test-pod ip a

1: lo:
    inet 127.0.0.1/8 scope host lo

2: tunl0@NONE:
    link/ipip 0.0.0.0 brd 0.0.0.0

4: calico@if142:
    inet 10.243.0.3/32 scope global calico

6: flannel@if143:
    inet 10.244.0.3/16 scope global flannel

140: eth0@if141:
    inet 10.16.0.5/16 brd 10.16.255.255 scope global eth0

Q&A

Configuring time

To allow for correct certificate verification, OpenNESS requires system time to be synchronized among all nodes and controllers in a system.

OpenNESS provides the possibility to synchronize a machine’s time with the NTP server. To enable NTP synchronization, change ntp_enable in inventory/default/group_vars/all/10-default.yml:

ntp_enable: true

Servers to be used instead of default ones can be provided using the ntp_servers variable in inventory/default/group_vars/all/10-default.yml:

ntp_servers: ["ntp.local.server"]

Setup static hostname

The following command is used in CentOS* to set a static hostname:

hostnamectl set-hostname <host_name>

As shown in the following example, the hostname must also be defined in /etc/hosts:

127.0.0.1   localhost localhost.localdomain localhost4 localhost4.localdomain4 <host_name>
::1         localhost localhost.localdomain localhost6 localhost6.localdomain6 <host_name>

In addition to being a unique hostname within the cluster, the hostname must also follow Kubernetes naming conventions. For example, only lower-case alphanumeric characters “-“ or “.” start and end with an alphanumeric character. Refer to K8s naming restrictions for additional details on these conventions.

Configuring the Inventory file

To execute playbooks, an inventory file inventory.yml must be defined in order to specify the target nodes on which the OpenNESS cluster(s) will be deployed.

The OpenNESS inventory contains three groups: all, controller_group, and edgenode_group.

  • all contains all the variable definitions relevant to the cluster:

    cluster_name: defines the name of the OpenNESS edge cluster flavor: the deployment flavor to be deployed to the OpenNESS edge cluster single_node_deployment: when set to true, mandates a single-node cluster deployment

  • controller_group defines the node to be set up as the OpenNESS Edge Controller

    NOTE: Because only one controller is supported, the controller_group can contain only one host.

  • edgenode_group defines the group of nodes that constitute the OpenNESS Edge Nodes.

    NOTE: All nodes will be joined to the OpenNESS Edge Controller defined in controller_group.

Example:

---
all:
  vars:
    cluster_name: central_office
    flavor: minimal          
    single_node_deployment: false
    limit:
controller_group:
  hosts:
    ctrl.openness.org:
      ansible_host: 10.102.227.154
      ansible_user: openness
edgenode_group:
  hosts:
    node01.openness.org:
      ansible_host: 10.102.227.11
      ansible_user: openness
    node02.openness.org:
      ansible_host: 10.102.227.79
      ansible_user: openness
edgenode_vca_group:
  hosts:
ptp_master:
  hosts:
ptp_slave_group:
  hosts:

In this example, a cluster named as central_office is deployed using the pre-defined deployment flavor minimal that is composed of one controller node ctrl.openness.org and 2 edge nodes: node01.openness.org and node02.openness.org.

Exchanging SSH keys between hosts

Exchanging SSH keys between hosts permits a password-less SSH connection from the host running Ansible to the hosts being set up.

In the first step, the host running Ansible (usually the Edge Controller host) must have a generated SSH key. The SSH key can be generated by executing ssh-keygen and obtaining the key from the output of the command.

The following is an example of a key generation, in which the key is placed in the default directory (/root/.ssh/id_rsa), and an empty passphrase is used.

# ssh-keygen

Generating public/private rsa key pair.
Enter file in which to save the key (/root/.ssh/id_rsa):  <ENTER>
Enter passphrase (empty for no passphrase):  <ENTER>
Enter same passphrase again:  <ENTER>
Your identification has been saved in /root/.ssh/id_rsa.
Your public key has been saved in /root/.ssh/id_rsa.pub.
The key fingerprint is:
SHA256:vlcKVU8Tj8nxdDXTW6AHdAgqaM/35s2doon76uYpNA0 root@host
The key's randomart image is:
+---[RSA 2048]----+
|          .oo.==*|
|     .   .  o=oB*|
|    o . .  ..o=.=|
|   . oE.  .  ... |
|      ooS.       |
|      ooo.  .    |
|     . ...oo     |
|      . .*o+.. . |
|       =O==.o.o  |
+----[SHA256]-----+

In the second step, the generated key must be copied to every host from the inventory, including the host on which the key was generated, if it appears in the inventory (e.g., if the playbooks are executed from the Edge Controller host, the host must also have a copy of its key). It is done by running ssh-copy-id. For example:

# ssh-copy-id root@host

/usr/bin/ssh-copy-id: INFO: Source of key(s) to be installed: "/root/.ssh/id_rsa.pub"
The authenticity of host '<IP> (<IP>)' can't be established.
ECDSA key fingerprint is SHA256:c7EroVdl44CaLH/IOCBu0K0/MHl8ME5ROMV0AGzs8mY.
ECDSA key fingerprint is MD5:38:c8:03:d6:5a:8e:f7:7d:bd:37:a0:f1:08:15:28:bb.
Are you sure you want to continue connecting (yes/no)? yes
/usr/bin/ssh-copy-id: INFO: attempting to log in with the new key(s), to filter out any that are already installed
/usr/bin/ssh-copy-id: INFO: 1 key(s) remain to be installed -- if you are prompted now it is to install the new keys
root@host's password:

Number of key(s) added: 1

Now, try logging into the machine, with:   "ssh 'root@host'"
and check to make sure that only the key(s) you wanted were added.

To make sure the key is copied successfully, try to SSH into the host: ssh 'root@host'. It should not ask for the password.

NOTE: Where non-root user is used for example openness the command should be replaced to ssh openness@host. For more information about non-root user please refer to: The non-root user on the OpenNESS Platform

Setting proxy

If a proxy is required to connect to the Internet, it is configured via the following steps:

  • Edit the proxy_ variables in the inventory/default/group_vars/all/10-default.yml file.
  • Set the proxy_enable variable in inventory/default/group_vars/all/10-default.yml file to true.
  • Append the network CIDR (e.g., 192.168.0.1/24) to the proxy_noproxy variable in inventory/default/group_vars/all/10-default.yml.

Sample configuration of inventory/default/group_vars/all/10-default.yml:

# Setup proxy on the machine - required if the Internet is accessible via proxy
proxy_enable: true
# Clear previous proxy settings
proxy_remove_old: true
# Proxy URLs to be used for HTTP, HTTPS and FTP
proxy_http: "http://proxy.example.org:3128"
proxy_https: "http://proxy.example.org:3129"
proxy_ftp: "http://proxy.example.org:3128"
# Proxy to be used by YUM (/etc/yum.conf)
proxy_yum: ""
# No proxy setting contains addresses and networks that should not be accessed using proxy (e.g., local network and Kubernetes CNI networks)
proxy_noproxy: ""

Sample definition of no_proxy environmental variable for Ansible host (to allow Ansible host to connect to other hosts):

export no_proxy="localhost,127.0.0.1,10.244.0.0/24,10.96.0.0/12,192.168.0.0/24"

Obtaining installation files

There are no specific restrictions on the directory into which the OpenNESS directories are cloned. When OpenNESS is built, additional directories will be installed in /opt. It is recommended to clone the project into a directory such as /home.

Setting Git

GitHub token

NOTE: Only required when cloning private repositories. Not needed when using github.com/open-ness repositories.

To clone private repositories, a GitHub token must be provided.

To generate a GitHub token, refer to GitHub help - Creating a personal access token for the command line.

To provide the token, edit the value of git_repo_token variable in inventory/default/group_vars/all/10-default.yml.

Customize tag/branch/sha to checkout on edgeservices repository

A specific tag, branch, or commit SHA on edgeservices repository can be checked out by setting the git_repo_branch variable in inventory/default/group_vars/all/10-open.yml.

git_repo_branch: master
# or
git_repo_branch: openness-20.03

Customization of kernel, grub parameters, and tuned profile

Converged Edge Experience Kits provide an easy way to customize the kernel version, grub parameters, and tuned profile. For more information, refer to the Converged Edge Experience Kits guide.