Edge Integration Cell on SUSE #

This guide describes how to prepare your infrastructure for the installation of Edge Integration Cell on Rancher Kubernetes Engine 2 using Rancher Prime. It will guide you through the steps of:

Note

This guide does not contain information about sizing your landscapes. Visit https://help.sap.com/docs/integration-suite?locale=en-US and search for the "Edge Integration Cell Sizing Guide".

Note

In this guide, we use $ and # for shell commands, where # means that the command needs to be executed as a root user and $ means that the command can be run by any user.

The support matrix below shows which versions of the given software we’ll use in this guide.

Important

If you want to use different versions of SUSE Linux Enterprise Micro, Rancher Prime, Rancher Kubernetes Engine 2 or Longhorn, make sure to check the support matrix for the related solutions you want to use: https://www.suse.com/suse-rancher/support-matrix/all-supported-versions/
For Redis and PostgreSQL, make sure to pick versions compatible to Edge Integration Cell, which can be found in https://me.sap.com/notes/3247839 .
Other versions of MetalLB or cert-manager can be used but may have not been tested.

* Only needed if you want to set up Rancher Prime in a high availability setup.

Additionally,

To run Edge Integration Cell in a production-ready and supported way, you need to set up multiple Kubernetes clusters and their nodes. Those comprise a Kubernetes cluster where you will install Rancher Prime to set up and manage the production and non-production clusters. For this Rancher Prime cluster, we recommend using three Kubernetes nodes and a load balancer.

The Edge Integration Cell will need to run in a dedicated Kubernetes cluster. For an HA setup of this cluster, we recommend using three Kubernetes control planes and three Kubernetes worker nodes.

For a graphical overview of what is needed, take a look at the landscape overview:

We will use this graphic overview in the guide to illustrate what the next step is and what it is for.

Starting with installing the operating system of each machine or Kubernetes node, we will walk you through all the steps you need to take to get a fully set-up Kubernetes landscape for deploying Edge Integration Cell.

There are several ways to install SUSE Linux Enterprise Micro 5.4. For this best practice guide, we use the installation method via graphical installer. But in cloud-native deployments it is highly recommended to use Infrastructur- as-Code technologies to fully automate the deployment and lifecycle processes.

5.1 Installation #

 

On each server in your environment for Edge Integration Cell and Rancher Prime, install SUSE Linux Enterprise Micro 5.4 as the operating system. The manual installation is described in the SUSE Linux Enterprise Micro 5.4 Deployment Guide in our Documentation SLE Micro Deployment Guide.

At the end of the installation process in the summary windows you need to check if these Security Settings are configured:

• The firewall will be disabled.

• The SSH service will be enabled.

• SELinux will be set in permissive mode.

Set SELinux into permissive mode, because otherwise, some components of the Edge Integration Cell violate SELinux rules, and the application will not work.

Tip

If you have already set up all machines and the operating system, skip this chapter.

$ transactional-update register -r REGISTRATION_CODE -e EMAIL_ADDRESS

$ transactional-update register -r REGISTRATION_CODE -e EMAIL_ADDRESS \
--url "https://suse_register.example.com/"

$ transactional-update

$ systemctl --now disable transactional-update.timer

$ transactional-update pkg install lvm2 jq nfs-client cryptsetup open-iscsi

$ reboot

$ systemctl enable iscsid  --now

$ pvcreate /dev/vdb

$ vgcreate vgdata /dev/vdb

$ lvcreate -n lvlonghorn -l100%FREE vgdata

$ mkfs.xfs /dev/vgdata/lvlonghorn

$ mkdir -p /var/lib/longhorn

$ echo -e "/dev/vgdata/lvlonghorn /var/lib/longhorn xfs defaults 0 0" >> /etc/fstab

$ mount -a

By now you should have installed the operating system on every Kubernetes node. You are now ready to install a Rancher Prime cluster. Taking a look again on the landscape overview, this means, we will now cover how to set up the upper part of the given graphic:

6.1 Preparation #

 

To have a highly available Rancher Prime setup, you need a load balancer for your Rancher Prime nodes. This section describes how to set up a custom load balancer using haproxy. If you already have a load balancer, you can use that to make Rancher Prime highly available.

If you do not plan to set up a highly available Rancher Prime cluster, you can skip this section.

6.1.1 Installing an haproxy-based load balancer #

 

Set up a virtual machine or a bare metal server with SUSE Linux Enterprise Server and SUSE Linux Enterprise High Availability or use SUSE Linux Enterprise Server for SAP Applications. Install the haproxy package.

$ zypper in haproxy

Create the configuration for haproxy. Find an example configuration file for haproxy below and adapt for the actual environment.

# cat <<EOF > /etc/haproxy/haproxy.cfg
global
        log /dev/log    local0
        log /dev/log    local1 notice
        chroot /var/lib/haproxy
        # stats socket /run/haproxy/admin.sock mode 660 level admin
        stats timeout 30s
        user haproxy
        group haproxy
        daemon

        # general hardlimit for the process of connections to handle, this is separate to backend/listen
        # Added in 'global' AND 'defaults'!!! - global affects only system limits (ulimit/maxsock) and defaults affects only listen/backend-limits - hez
        maxconn 400000

        # Default SSL material locations
        ca-base /etc/ssl/certs
        crt-base /etc/ssl/private

        tune.ssl.default-dh-param 2048

        # Default ciphers to use on SSL-enabled listening sockets.
        # For more information, see ciphers(1SSL). This list is from:
        #  https://hynek.me/articles/hardening-your-web-servers-ssl-ciphers/
        ssl-default-bind-ciphers ECDH+AESGCM:DH+AESGCM:ECDH+AES256:DH+AES256:ECDH+AES128:DH+AES:ECDH+3DES:DH+3DES:RSA+AESGCM:RSA+AES:RSA+3DES:!aNULL:!MD5:                            !DSS
        ssl-default-bind-options ssl-min-ver TLSv1.2 no-tls-tickets

defaults
        mode tcp
        log     global
        option  tcplog
        option  redispatch
        option  tcpka
        option  dontlognull
        retries 2
        timeout connect 5s
        timeout client  5s
        timeout server  5s
        timeout tunnel  86400s
        maxconn 400000

listen stats
        bind *:9000
        mode http
        stats hide-version
        stats uri /stats

listen rancher_apiserver
        bind my_lb_address:6443
        option httpchk GET /healthz
        http-check expect status 401
        server mynode1 mynode1.domain.local:6443 check check-ssl verify none
        server mynode2 mynode2.domain.local:6443 check check-ssl verify none
        server mynode3 mynode3.domain.local:6443 check check-ssl verify none
listen rancher_register
        bind my_lb_address:9345
        option httpchk GET /ping
        http-check expect status 200
        server mynode1 mynode1.domain.local:9345 check check-ssl verify none
        server mynode2 mynode2.domain.local:9345 check check-ssl verify none
        server mynode3 mynode3.domain.local:9345 check check-ssl verify none

listen rancher_ingress80
        bind my_lb_address:80
        option httpchk GET /
        http-check expect status 404
        server mynode1 mynode1.domain.local:80 check
        server mynode2 mynode2.domain.local:80 check
        server mynode3 mynode3.domain.local:80 check

listen rancher_ingress443
        bind my_lb_address:443
        option httpchk GET /
        http-check expect status 404
        server mynode1 mynode1.domain.local:443 check check-ssl verify none
        server mynode2 mynode2.domain.local:443 check check-ssl verify none
        server mynode3 mynode3.domain.local:443 check check-ssl verify none
EOF

Check the configuration file:

$ haproxy -f /path/to/your/haproxy.conf -c

Enable and start the haproxy load balancer:

$ systemctl enable haproxy
$ systemctl start haproxy

Do not forget to restart or reload haproxy if any changes are made to the haproxy configuration file.

6.1.2 Installing RKE2 #

 

To install RKE2, the script provided at https://get.rke2.io can be used as follows:

$ curl -sfL https://get.rke2.io | INSTALL_RKE2_VERSION=v1.28.13-rke2r1 sh

For HA setups, it is necessary to create RKE2 cluster configuration files in advance. On the first master node:

$ mkdir -p /etc/rancher/rke2
$ cat <<EOF > /etc/rancher/rke2/config.yaml
token: 'your cluster token'
system-default-registry: registry.rancher.com
tls-san:
  - FQDN of fixed registration address on load balancer
  - other hostname
  - IP v4 address
EOF

Create configuration files for additional cluster nodes:

$ cat <<EOF > /etc/rancher/rke2/config.yaml
server: https://"FQDN of registration address":9345
token: 'your cluster token'
system-default-registry: registry.rancher.com
tls-san:
  - FQDN of fixed registration address on load balancer
  - other hostname
  - IP v4 address
EOF

Important

You also need take about ETCD Snapshots and to perfom backups of your Rancher instance. This is not part of this Document and you can find more information in our Documentation.

Important

For security reasons, we generally recommend activating the CIS profile when installing RKE2. This is currently still being validated and will be included in the documentation at a later date.

Now enable and start the RKE2 components and run the following command on each cluster node:

$ systemctl enable rke2-server --now

To verify the installation, run the following command:

$ /var/lib/rancher/rke2/bin/kubectl --kubeconfig /etc/rancher/rke2/rke2.yaml get nodes

For convenience, the kubectl binary can be added to the $PATH and the given kubeconfig can be set via an environment variable:

$ export PATH=$PATH:/var/lib/rancher/rke2/bin/
$ export KUBECONFIG=/etc/rancher/rke2/rke2.yaml

6.1.3 Installing Helm #

 

To install Rancher Prime and some of its required components, you need to use Helm.

One way to install Helm is to run:

$ curl https://raw.githubusercontent.com/helm/helm/main/scripts/get-helm-3 | bash

6.1.4 Installing cert-manager #

 

To install the cert-manager package, do the following:

$ kubectl create namespace cert-manager

How to create the imagePullSecret is described in the Section 11.1, “Creating an imagePullSecret for the Rancher Application Collection”.

6.1.4.1 Installing the application #

 

Before you can install the application, you need to login into the registry. You can find the instruction in Section 11.2, “Login into the Application Collection Registry”

$ helm install cert-manager oci://dp.apps.rancher.io/charts/cert-manager \
--set crds.enabled=true \
--set-json 'global.imagePullSecrets=[{"name":"application-collection"}]' \
--namespace=cert-manager \
--version 1.15.2

$ helm repo add rancher-prime https://charts.rancher.com/server-charts/prime

$ kubectl create namespace cattle-system

$ helm install rancher rancher-prime/rancher \
    --namespace cattle-system \
    --set hostname=<your.domain.com> \
    --set replicas=3

$ kubectl -n cattle-system rollout status deploy/rancher-prime

After having installed the Rancher Prime cluster, we can now make use this one to create the Rancher Kubernetes Engine 2 clusters for Edge Integration Cell. SAP recommends to set up not only a production landscape, but to have QA / Dev systems for Edge Integration Cell. Both can be set up the same way using Rancher Prime. How to do this is covered in this chapter. Looking at the landscape overview again, we will now deal with setting up the lower part of the given graphic:

Creating new RKE2 clusters is very easy when using Rancher Prime.

Go to the home menu of your Rancher Prime instance. Click the Create button on the right side of the screen, as shown here:

Figure 1: Rancher home menu #

 

The window shows you the available options for creating new Kubernetes clusters. Make sure the toggle button on the right side of the screen is set to RKE2/K3s as shown below:

Figure 2: Rancher RKE version selection #

 

If you want to create Kubernetes clusters on existing (virtual) machines, select the Custom option at the very bottom, as shown in the image below:

Figure 3: Rancher create custom cluster #

 

Next, you will see a window to configure your Kubernetes cluster. It will look similar to the image below:

Figure 4: Rancher create custom cluster config #

 

Here, you need to name the cluster. The name will only be used within Rancher Prime. It will not affect your workloads. In the next step, make sure you select a Kubernetes version that is supported by the workload you want to deploy.

If you do not have any further requirements to Kubernetes, you can click the Create button at the very bottom. In any other cases talk to your administrators before making adjustements.

After you clicked Create, you should see a screen like this:

Figure 5: Rancher create registration #

 

Now, in a first step, select the roles your node(s) should receive. A common high avaiability setup holds:

The next step is to copy the registration command to the target machines' shell and execute it. If your Rancher Prime instance holds a self-signed certifcate, make sure to activate the text bar holding the registration command in the check box below .

You can run the command on all nodes in parallel. You do not need to wait until a single node is down. When all machines are registered, you can see the cluster status at the top, changing from "updating" to "active". At this point in time, your Kubernetes cluster is ready to be used.

This chapter details the minimum requirements to install Longhorn and describes three different ways for the installation. For more details, visit https://longhorn.io/docs/1.6.2/deploy/install/

$ curl -sSfL https://raw.githubusercontent.com/longhorn/longhorn/v1.6.2/scripts/environment_check.sh | bash

$ helm repo add rancher-v2.8-charts https://raw.githubusercontent.com/rancher/charts/release-v2.8
$ helm repo update
$ helm upgrade --install longhorn-crd rancher-v2.8-charts/longhorn-crd \
--namespace longhorn-system \
--create-namespace
$ helm upgrade --install longhorn rancher-v2.8-charts/longhorn \
--namespace longhorn-system

In the following chapter we present an example for setting up MetalLB, Redis and PostgreSQL.

Note

Keep in mind that the descriptions and instructions below might differ from the deployment you need for your specific infrastructure and use cases.

9.1 Logging in to Rancher Application Collection #

 

To access the Rancher Application Collection you need to login. Therefore, you can use the console and Helm client. The easiest way to do so is to use the built-in shell in Rancher Prime. To access it, navigate to your cluster and click Kubectl Shell as shown below:

Figure 6: Rancher Shell Access #

 

A shell will open as shown in the image:

Figure 7: Rancher Shell Overview #

 

You must log in to Rancher Application Collection. This can be done as follows:

$ helm registry login dp.apps.rancher.io/charts -u <yourUser> -p <your-token>

$ kubectl create namespace metallb

imagePullSecrets:
  - name: application-collection

$ helm install metallb oci://dp.apps.rancher.io/charts/metallb \
-f values.yaml \
--namespace=metallb \
--version 0.14.7

$ cat <<EOF >iprange.yaml
apiVersion: metallb.io/v1beta1
kind: IPAddressPool
metadata:
  name: first-example-pool
  namespace: metallb
spec:
  addresses:
  - 192.168.1.240/32
EOF

$ cat <<EOF > l2advertisement.yaml
apiVersion: metallb.io/v1beta1
kind: L2Advertisement
metadata:
  name: example
  namespace: metallb
EOF

$ kubectl apply -f iprange.yaml
$ kubectl apply -f l2advertisement.yaml

$ kubectl create namespace redis

images:
  redis:
    # -- Image name to use for the Redis container
    repository: dp.apps.rancher.io/containers/redis
    # -- Image tag to use for the Redis container
    tag: 7.2.5
storageClassName: "longhorn"
global:
  imagePullSecrets: ["application-collection"]
architecture: cluster
nodeCount: 3
auth:
  password: <redisPW>
tls:
  # -- Enable TLS
  enabled: true
  # -- Whether to require Redis clients to authenticate with a valid certificate (authenticated against the trusted root CA certificate)
  authClients: false
  # -- Name of the secret containing the Redis certificates
  existingSecret: "redisCert"
  # -- Certificate filename in the secret
  certFilename: "server.pem"
  # -- Certificate key filename in the secret
  keyFilename: "server.key"
  #  CA certificate filename in the secret - needs to hold the CA.crt and the server.pem
  caCertFilename: "root.pem"

$ helm install redis oci://dp.apps.rancher.io/charts/redis \
-f values.yaml \
--namespace=redis
--version

$ kubectl create namespace postgresql

global:
  # -- Global override for container image registry pull secrets
  imagePullSecrets: ["application-collection"]
images:
  postgresql:
    # -- Image name to use for the PostgreSQL container
    repository: dp.apps.rancher.io/containers/postgresql
    # -- Image tag to use for the PostgreSQL container
    tag: "15.7"
auth:
  # -- PostgreSQL username for the superuser
  postgresUsername: postgres
  # -- PostgreSQL password for the superuser
  postgresPassword: "<your_password>"
  # -- Replication username
  replicationUsername: replication
  # -- Replication password
  replicationPassword: "<your_password>"
tls:
  # -- Enable SSL/TLS
  enabled: false
  # -- Name of the secret containing the PostgreSQL certificates
  existingSecret: "postgresqlcert"
  # -- Whether or with what priority a secure SSL TCP/IP connection will be negotiated with the server. Valid values: prefer (default), disable, allow, require, verify-ca, verify-full
  sslMode: "verify-full"
  # -- Certificate filename in the secret (will be ignored if empty)
  certFilename: "server.pem"
  # -- Certificate key filename in the secret (will be ignored if empty)
  keyFilename: "server.key"
  # -- CA certificate filename in the secret (will be ignored if empty)
  caCertFilename: "root.pem"
persistentVolumeClaimRetentionPolicy:
  whenDeleted: Delete

$ helm install postgres oci://dp.apps.rancher.io/charts/postgres -f values.yaml --namespace=postgres

At this point, you should be able to deploy Edge Integration Cell. Follow the instructions at https://help.sap.com/docs/integration-suite/sap-integration-suite/setting-up-and-managing-edge-integration-cell to install Edge Integration Cell in your prepared environments.

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